Journal articles: 'Indented Head'

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Ebsary, B. A. "Ceramotylenchus tesselatus n. gen., n. sp. and Pleurotylenchus minor n. sp. (Nematoda: Tylenchida) from Alabama." Canadian Journal of Zoology 64, no. 1 (January 1, 1986): 238–42. http://dx.doi.org/10.1139/z86-037.

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A new genus and species of Duosulciinae and a new species of Pleurotylenchus are described and illustrated. Ceramotylenchus tesselatus n. gen., n. sp. is distinguished by having a cuplike oral disc, two crenate lateral incisures, absence of lateral vulval flaps, and alternating rows of blocks on the head and body that gives a tilelike appearance. Pleurotylenchus minor n. sp. is distinguished from P. sachsi by a smaller body size, more posterior vulva, shorter stylet, laterally indented head annules, and by the lateral field that begins on the first body annule.

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Charchar, João, Maria Jose Charchar, Jonathan Eisenback, and Maria Esther Boiteux. "Meloidogyne pisi n. sp. (Nematoda: Meloidogynidae), a root-knot nematode parasitising pea in Brazil." Nematology 10, no. 4 (2008): 479–93. http://dx.doi.org/10.1163/156854108784513905.

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AbstractMeloidogyne pisi n. sp. is described and illustrated from specimens obtained from roots of pea cv. Mikado in Brasilia, Brazil. The female perineal pattern is variable in shape, most are rounded to ovoid, whereas others have a moderately high, squarish dorsal arch, and can be marked with several striae parallel to the vulva or may be nearly free of striae. Lateral fields may contain a few irregular, wavy, transverse striae or be difficult to discern. Female medial lips are wide and long, sometimes with distinctly indented outer margins; the lateral lips are large and triangular, head annule is wide and marked by incomplete annulations and transverse folds. Stylet is 13-17 μm long with large, elongated knobs and a shaft that is cylindrical, straight and thick. Lumen lining of pharynx containing numerous rounded cuticular thickenings throughout its length; excretory pore located between base of stylet and median bulb. Males are 893-2510 μm long with a 19-26 μm long stylet bearing large elongated knobs, shaft marked with small, rounded projections. Second-stage juveniles are 374-463 μm long with medial lips often indented medially and 10-11 μm long stylet. Tail slender, 42-66 μm long with large irregular annules in posterior region, a slightly pointed tip and hyaline region 9-17 μm long. Many galls and egg masses are produced on tomato, tobacco and varieties of pea and bean. Few galls occur on watermelon and corn and reproduction is poor on pepper. No reproduction occurs on peanut, cotton or soybean.

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Folęga, Piotr. "Impact of Structural Characteristics of Flexspline on the Stresses Occurring at the Tooth Space Bottom." Advanced Materials Research 1036 (October 2014): 631–36. http://dx.doi.org/10.4028/www.scientific.net/amr.1036.631.

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The author of the article applied the boundary element method (BEM) to determine stresses occurring in a toothed rim of a flexspline. The relevant numerical calculations were conducted using software developed at the Faculty of Transport of the Silesian University of Technology. The numerical analysis conducted for flexsplines entailed the impact exerted by parameters of an indented toothed flexspline rim (number of teeth, addendum modification coefficient) and of a gear tool (gear tool head curve radius, pressure angle) on values of the stresses occurring at the tooth space bottom. Results of the said calculations have been depicted as curves of dependences between stresses at the tooth space bottom in the function of the number of flexspline rim teeth on constant values of the addendum modification coefficient. The cumulative diagrams developed based on the results of the calculations conducted may provide guidelines as to the manner of designing flexsplines for harmonic drives.

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BRUCE, NIEL L. "A new deep-water species of Natatolana (Crustacea: Isopoda: Cirolanidae) from the Chatham Rise, eastern New Zealand." Zootaxa 265, no. 1 (August 11, 2003): 1. http://dx.doi.org/10.11646/zootaxa.265.1.1.

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Natatolana rekohu sp. nov. from the Chatham Rise, off southeastern New Zealand is described and figured. Natatolana rekohu was collected at a depth of 2799 metres, close to the greatest recorded depth for this genus. The species is a scavenger, and was feeding on dead fish in a sediment trap. Natatolana rekohu is characterised by: reduced eyes; strongly indented anterior margin of the head; pentagonal frontal lamina, with weakly convex lateral margins; pleonites 1 and 2 not produced, 3 weakly and pleonite 4 rounded; pereopods 1 and 2 usually with 5 or 6 setae on the propodal palm. In males the large flat and widely separated penes and the strongly curved, wide and terminally toothed appendix masculina are additional diagnostic characters. As in most Natatolana the numbers of robust setae on the margins of the uropodal rami and pleotelson are also important in making a correct identification.

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Taylor, Blake E. S., Irene Say, Pratit Patel, and Luke D. Tomycz. "Microsurgical Clip Ligation of an Unruptured Azygos Bifurcation Aneurysm Indented by the Falx Cerebri: 3-Dimensional Operative Video." Operative Neurosurgery 19, no. 3 (January 13, 2020): E294. http://dx.doi.org/10.1093/ons/opz393.

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Abstract Dissecting pericallosal aneurysms from the falx cerebri is technically challenging, as one must release the adherent dome but minimize shearing injury, which could result in intraoperative rupture. We discuss a 51-yr-old woman with a history of hypertension and smoking who presented with severe headaches and was found to have a 6-mm unruptured, multilobulated pericallosal aneurysm abutting the falx, with anterior and superior projecting domes on either side. She also had an azygos anterior cerebral artery (ACA), a rare anatomic variant associated with pericallosal aneurysms, where both A1 segments form a single A2. After considering endovascular and open surgical techniques, we proceeded with clip ligation given her younger age, smoking history, daughter aneurysms seen on angiography, and azygos ACA. We positioned her supine with her head turned lateral, left side down to maximize gravitational retraction, mapped a bicoronal incision, and performed a small craniotomy, followed by an interhemispheric approach. Rather than cutting the falx around the dome, a described technique that risks blind vessel injury, we temporarily clipped inflow vessels to reduce the dome's turgor and sharply and bluntly dissected apart its attachments, which freed the aneurysm from beneath the falx and allowed visualization of associated vessels. Using suction to manipulate the dome, we then placed stacked, angled clips, and used a micro-Doppler to confirm brisk inflow and outflow. Postoperatively, she was neurologically intact, and her angiogram showed no residual aneurysm. Our 3-dimensional video demonstrates a safer, alternative approach to treating this rare aneurysm with its associated anatomical variant. Patient consented to her clinical presentation and microscope media being used for academic purposes.

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Wang, Bo, Kathleen M. C. Sullivan, and Kathy Beckingham. "Drosophila Calmodulin Mutants With Specific Defects in the Musculature or in the Nervous System." Genetics 165, no. 3 (November 1, 2003): 1255–68. http://dx.doi.org/10.1093/genetics/165.3.1255.

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Abstract We have studied lethal mutations in the single calmodulin gene (Cam) of Drosophila to gain insight into the in vivo functions of this important calcium sensor. As a result of maternal calmodulin (CaM) in the mature egg, lethality is delayed until the postembryonic stages. Prior to death in the first larval instar, Cam nulls show a striking behavioral abnormality (spontaneous backward movement) whereas a mutation, Cam7, that results in a single amino acid change (V91G) produces a very different phenotype: short indented pupal cases and pupal death with head eversion defects. We show here that the null behavioral phenotype originates in the nervous system and involves a CaM function that requires calcium binding to all four sites of the protein. Further, backward movement can be induced in hypomorphic mutants by exposure to high light levels. In contrast, the V91G mutation specifically affects the musculature and causes abnormal calcium release in response to depolarization of the muscles. Genetic interaction studies suggest that failed regulation of the muscle calcium release channel, the ryanodine receptor, is the major defect underlying the Cam7 phenotype.

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Castillo, Pablo, Alberto Troccoli, and Nicola Vovlas. "Hemicriconemoides macrodorus n. sp. with observations on two other species of the genus (Nematoda: Criconematidae)." Nematology 2, no. 4 (2000): 395–405. http://dx.doi.org/10.1163/156854100509259.

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AbstractHemicriconemoides macrodorus n. sp. is described and illustrated from a bisexual population collected in a natural habitat at Santa Elena, Jaén, southern Spain. The new species falls into the 'group 2', based on lip patterns (Decraemer & Geraert, 1992), which contains 13 other species characterised by a cephalic region with an offset, raised, narrower oral disc, followed by broader head annuli. The main distinctive characters of the new species are: lip region truncate, very long stylet (90-100 μ m), long body 548-750 μ m, R = 127-148, conical tail, VL/VB = 1.0-1.5, spined juvenile cuticular ornamentation (multispined scales, indented at their edges) arranged in ten alternate rows, and male lateral field with four incisures. Morphometric data, illustrations and brief descriptions are presented for an Italian population of H. ortonwilliamsi Ye & Siddiqi, 1994, while, for the first time, morphometric data and illustrations are given for the male and the juvenile of H. alexis Vovlas, 1980. Hemicriconemoides macrodorus n. sp. et observations sur deux autres espèces du genre (Nematoda: Criconematidae) - Hemicriconemoides macrodorus n. sp. est décrit et figuré d'une population bisexuelle collectée dans un habitat naturel à Santa Elena, Jaén, le Sud d'Espagne. La nouvelle espèce appartient au ''groupe 2'' sur la base de la morphologie labiale (Decraemer & Geraert, 1992), groupe comptant 13 autres espèces caractérisées par une région céphalique avec un disque labial séparé du reste du corps, proéminent et rétréci, suivi des anneaux céphaliques plus larges. Les principaux caractères distinctifs de la nouvelle espèce sont: région labiale tronquée, très long stylet (90-100 μ m), corps long 548-750 μ m, R = 127-148, queue conique, VL/VB = 1.0- 1.5, ornementations cuticulaires des juvéniles avec épines (écailles avec plusieurs épines, indentées sur les côtés) arrangées en dix rangées alternées, et champ latéral du mâle comportant quatre incisures. Des données morphométriques, des illustrations et de brèves descriptions sont présentées pour une population italienne de H. ortonwilliamsi Ye & Siddiqi, 1994, alors que, pour la première fois, des données morphométriques et des illustrations sont produites pour le mâle et les juvéniles de H. alexis Vovlas, 1980.

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Putra, I. B. Werdi, Yohanes Setiyo, and I. Gusti Ngurah Apriadi Aviantara. "Kajian Kualitas Beras Sosoh Dari Berbagai Macam Ukuran Daya Mesin Penggiling." Jurnal BETA (Biosistem dan Teknik Pertanian) 8, no. 1 (September 3, 2019): 130. http://dx.doi.org/10.24843/jbeta.2020.v08.i01.p16.

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Rice is a staple food for the people of Indonesia. Even though Indonesia is an agrarian country, Indonesia currently imports rice. In producing rice from rice there are obstacles. One of the main obstacles is post-harvest handling of rice with high yield loss during post-harvest. The amount of post-harvest loss occurs because most farmers still use traditional methods or the handling is not good and right. The purpose of this study was to determine the relationship between the capacity of the grinding machine and the quality of sosoh rice produced by the mill and to know the quality comparison of various types of grinding machine capacity. The research was carried out in the area of ??Wanasari Village, Tabanan-Bali to find out the quality of sosoh rice in the region. Head Rice is broken rice grains, both healthy and defective, which have a size greater than or equal to 6/10 part of the average length size of whole rice grains that can pass through the surface of the indented plate basin with a requirement of 4.2 mm hole size. Rice husk is a protective cover from rice grains which is separated from seeds during the grinding process. In the grinding process, there is rice which remains the husk which is caused by the power / rpm of the grinding machine which is too low because the friction force produced by the engine is not sufficient for the overall release of rice husk

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Gao, Jinling, Nesredin Kedir, Boon Him Lim, Yizhou Nie, Xuedong Zhai, and Weinong Chen. "Transverse Loading on Single High-Performance Fibers by Round-Head Indenters and the Fibers’ Failure Visualization." Fibers 10, no. 6 (May 30, 2022): 48. http://dx.doi.org/10.3390/fib10060048.

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High-performance fibers are well-known for their high stiffness and strength under axial tension. However, in their many applications as critical components of textiles and composites, transverse loads widely exist in their normal service life. In this study, we modified a micro material testing system to transverse load single fibers using round-head indenters. By integrating the loading platform with the Scanning Electron Microscopy (SEM) operating at a low-vacuum mode, we visualized the failure processes of fibers without conductive coatings. Post-fracture analysis was conducted to provide complementary information about the fibers’ failure. The energy dissipation was compared with the axial tensile experiments. Three inorganic and two organic fibers were investigated, namely carbon nanotube, ceramic, glass, aramid, and ultrahigh molecule weight polyethylene fibers. Different failure characteristics were reported. It is revealed that the organic fibers had higher energy dissipation than the inorganic fibers under the transverse loading by the round-head indenters. The fiber’s energy dissipation under transverse loading was no more than 17.9% of that subjected to axial tension. Such a reduced energy dissipation is believed to be due to the stress concentration under the indenter. It is suggested that the fiber’s material constituent, structural characteristics, and stress concentration under the indenter should be considered in the fiber model for textiles and composites.

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Javaheri, Ehsan, Verdiana Kumala, Alireza Javaheri, Reza Rawassizadeh, Janot Lubritz, Benjamin Graf, and Michael Rethmeier. "Quantifying Mechanical Properties of Automotive Steels with Deep Learning Based Computer Vision Algorithms." Metals 10, no. 2 (January 22, 2020): 163. http://dx.doi.org/10.3390/met10020163.

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This paper demonstrates that the instrumented indentation test (IIT), together with a trained artificial neural network (ANN), has the capability to characterize the mechanical properties of the local parts of a welded steel structure such as a weld nugget or heat affected zone. Aside from force-indentation depth curves generated from the IIT, the profile of the indented surface deformed after the indentation test also has a strong correlation with the materials’ plastic behavior. The profile of the indented surface was used as the training dataset to design an ANN to determine the material parameters of the welded zones. The deformation of the indented surface in three dimensions shown in images were analyzed with the computer vision algorithms and the obtained data were employed to train the ANN for the characterization of the mechanical properties. Moreover, this method was applied to the images taken with a simple light microscope from the surface of a specimen. Therefore, it is possible to quantify the mechanical properties of the automotive steels with the four independent methods: (1) force-indentation depth curve; (2) profile of the indented surface; (3) analyzing of the 3D-measurement image; and (4) evaluation of the images taken by a simple light microscope. The results show that there is a very good agreement between the material parameters obtained from the trained ANN and the experimental uniaxial tensile test. The results present that the mechanical properties of an unknown steel can be determined by only analyzing the images taken from its surface after pushing a simple indenter into its surface.

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Kikovic, Sasa, Ivan Tavcar, Tamara Dragovic, Petar Ristic, Jelena Karajovic, Dejan Marinkovic, Nenad Perisic, Sinisa Rusovic, and Zoran Hajdukovic. "Insulinoma- how to localize the tumor?" Vojnosanitetski pregled 75, no. 12 (2018): 1172–77. http://dx.doi.org/10.2298/vsp160222049k.

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Background/Aim. Arterial stimulation with calcium and venous sampling (ASVS) enables us to reach the goal of avoiding that any patient with insulinoma undergoes a blind surgical exploration. Since ASVS is both a functional and morphological localization procedure, its sensitivity is not influenced by factors that are causing the insensitivity of usual anatomical and morphological procedures. Based on our own experience in preoperative localization of insulinoma, we indented to show why we believe that ASVS should be performed to all patients regardless of data collected from other preoperative localization methods. Methods. We have analyzed the accuracy of preoperative localization methods retrospectively. First anatomical and morphological procedures like transabdominal ultrasound (US), endoscopic ultrasound (EUS), computed tomography (CT) and magnetic resonance imaging (MRI) were done. Then we analyzed the data collected during a functional procedure which, at the same time, allows regionalization (ASVS). To estimate the accuracy, the results of every single method were correlated with the operative findings in all sixteen cases. Results. Prior to ASVS, fourteen patients underwent US, fifteen had CT, MRI was performed in eight patients and EUS in thirteen. Using only one of these methods enabled identification of tumors in five patients, using two methods in six patients while three and four in one patient each. For three patients, none of these methods was successful. ASVS revealed that all seen tumors were functional except three of the six visualized with two methods (US and EUS). In two of these three cases, US and EUS localized the tumors in pancreatic tail/body while ASVS accurately identified the tumors in pancreatic head. For these patients US and EUS showed false positive results. In the third of these patients EUS showed the tumor localized in pancreatic head, while US and ASVS accurately pointed to tail. This, too, was a false positive result of EUS. ASVS successfully provided regionalization data in three patients where other visualization methods failed. Operative and later histological findings confirmed the accuracy of ASVS in all sixteen patients including two patients that previously underwent distal pancreatectomy based on false positive EUS findings. Conclusion. Two patients, with accurate insulinoma regionalization in pancreatic head, obtained with ASVS, previously underwent unsuccessful distal pancreatectomy based on the false positive EUS findings. The same goes to three other patients with the false positive results obtained with other anatomical and morphological findings, as well as those three patients that had no preoperative visualization with other methods prior to ASVS. Therefore we suggest ASVS performing in each suspected insulinoma patient before the surgery, regardless of the data collected using other methods. This would enable us to test functional characteristics of visualized findings and to regionalize part of pancreas with uncontrolled insulin secretion when no suspicious changes were found.

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Zhu, Y., L. Zhou, Ying Xue Yao, and Gui Wen Kang. "Molecular Dynamics Simulation for Single Crystal Aluminum Nano-Indentation Effect by Indenter Radius." Applied Mechanics and Materials 10-12 (December 2007): 401–5. http://dx.doi.org/10.4028/www.scientific.net/amm.10-12.401.

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Three dimension indenter model was established to replace the ideal shape indenter model in the study of nano-indentation simulation. The limitation of short of comparing to actual condition can be solved. Single crystal aluminum surface nano-indentation on the condition of arc indenter is researched by molecular dynamic simulation. The influences of different arc radius of indenter head to testing results are discussed and compared to experiment results. The results show that The measured hardness value increases with indenter head arc radius on the same indentation depth condition. With the increase of indentation depth, the difference between measured results with changed indenter head arc radius reduces gradually. When the indentation depth increase to a certain value, the arc effect of indenter head could be ignored, the measurement will be invariable.

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Wu, T. W., and C.-K. Lee. "Micro-impact technique and its applications." Journal of Materials Research 9, no. 3 (March 1994): 797–804. http://dx.doi.org/10.1557/jmr.1994.0797.

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A micro-impact tester has been designed and built by using a piezoelectric impact hammer as an impactor driver. During the course of an impact process, force interactions between the impactor and target surfaces were monitored continuously by a miniaturized piezoelectric loadcell embedded in the flying head assembly. A 3-sided pyramidal diamond indenter (Berkovich indenter) was used as an impactor. After having fully characterized such an impact system, the trajectory of the impactor can be calculated by using the corresponding prerecorded impact force interaction in a simulation program. The contact and returning velocities, kinetic energy loss of the impactor, and the impact penetration curve are the key pieces of information obtained from the simulation. Furthermore, the impact morphology can reveal failure mechanisms of materials by providing details such as indent shapes, coating fragment, chipping, crack type and size, and other information which are useful in assessing the fracture toughness of testing materials. The micro-impact testing was carried out in the contact velocity ranging from 0.3 to 2.0 m/s. Three types of materials such as metal, glass, and amorphous carbon were used in studying their distinct mechanical behavior under high rate indentations. The correlations among the impact conditions, energy losses, impact morphologies, and material responses are illustrated and discussed.

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King, William P., and Kenneth E. Goodson. "Thermomechanical Formation of Nanoscale Polymer Indents With a Heated Silicon Tip." Journal of Heat Transfer 129, no. 11 (January 15, 2007): 1600–1604. http://dx.doi.org/10.1115/1.2764088.

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In thermomechanical data storage, a heated atomic force microscope cantilever tip is in contact with and scans over a polymer film. Heating in the cantilever and cantilever tip induces local deformation of the polymer near the tip, with indents as small as 22nm. This paper reports a simple modeling approach for predicting heat and mass transfer in the cantilever tip and polymer with the goal of predicting indent formation conditions. The model accounts for subcontinuum conduction in the cantilever tip and for the time- and temperature-dependent mechanical properties of the polymer. Simulations predict steady state and transient indent formation, and the results compare well with data. For loading forces 30–200nN and a tip radius of 20nm, a cantilever temperature of 200°C is required to form an indent at steady state. For heating pulses as short as 5μs, the cantilever temperature required for bit formation is as high as 500°C. By quantifying the conditions required for indent formation, this work may improve the operation of heated probes for thermomechanical data storage.

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C., T. E. "SUCCESSFUL MANAGEMENT OF PROTRUSION OF THE TONGUE IN A FIVE-YEAR-OLD ENGLISH BOY (1805)." Pediatrics 79, no. 4 (April 1, 1987): 514. http://dx.doi.org/10.1542/peds.79.4.514.

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The following case report published in 1805 describes the successful treatment of a markedly protruding tongue in a young boy. The method is so simple that one wonders whether the author has not omitted something in the history. On Thursday, May 24, 1804, Ralph Heighington, five years old, was admitted into the Sunderland Dispensary. He had been much distressed with worms, and for this complaint he was put under my charge. He had every appearance of scrofula, such as ophthalmia tarsi, and marks under the chin from scrofulous sores, etc.; but what chiefly attracted my attention was his tongue, which was so much enlarged in length, breadth, and thickness, that it hung out of his mouth considerably below the chin. It had a very disgusting appearance. The upper part of it was rugose, and indented with a few longitudinal fissures. The dentes incisores were gone; and the few remaining molares were much diseased, and ready to drop out. He could not utter a single syllable, but appeared to understand everything I said to him. The tongue began to swell before he was a year old; and increased so rapidly, as to prevent him from learning to speak a word. By the use of a few vermifuge medicines, a large quantity of worms were expelled, and, with them, all the concomitant symptoms disappeared. The tongue remained still much the same, being protruded without the mouth about three inches. The more he endeavoured to pull it within his lips, the further it appeared to be protruded. I thought it expedient to ... push back the tongue, and shut the mouth; but the moment he withdrew his hand, it burst without the mouth, the same as before. I ordered the tongue to be returned into the mouth, and retained there by means of a silk handkerchief, which was passed below the chin, and the ends firmly fastened at the crown of the head. By this means the jaws were kept perfectly close together. At first he appeared very uneasy, but being relieved occasionally, by taking off the handkerchief for a few minutes, and replacing it again, he was enabled to bear it; and, in the course of five weeks, the tongue became of the natural size and appearance, and he could pronounce several short words very distinctly. By these means, a perfect cure was effected.

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Santo, Loredana, Erica Anna Squeo, and Federica Trovalusci. "Double Indentation of Laser Welded Butt Joints of Stainless Steel Sheets." Key Engineering Materials 410-411 (March 2009): 503–9. http://dx.doi.org/10.4028/www.scientific.net/kem.410-411.503.

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In this study, an easy and innovative technique for laser welded butt joint characterization is proposed. AISI 304 sheets, 1.25 mm in thickness, were welded in the butt configuration by means of a high power diode laser (HPDL). Different combinations of the process parameters were considered. For each combination, during the process different thermal cycles were induced in the material generating heat affected zones, which were subsequently tested by the double indentation test method. This test was performed on the sheets by means of two co-axial flat indenters, 1 mm in diameter, made of tungsten carbide (WC); the upper indenter penetrates at a constant rate (0.1 mm/min) into the material, whereas the lower indenter acts as a support. On each side of the seam, 10 indentations were performed at fixed positions with different distance from the centre of the seam, to obtain a load map correlated to the mechanical properties. By comparing the maps of the different laser welded joints, a clear effect of the laser scan speed and the power was found. Furthermore, a wake field effect is recognizable, in fact the loads are symmetric as regards the seam, and there is a clear trend in the direction of the laser path. These results confirm the effectiveness of this method, which is also suitable for on-line application because a very small indentation is left on the sheet.

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Polanco, Jonatan D., Carlos Jacanamejoy-Jamioy, Claudia L. Mambuscay, Jeferson F. Piamba, and Manuel G. Forero. "Automatic Method for Vickers Hardness Estimation by Image Processing." Journal of Imaging 9, no. 1 (December 30, 2022): 8. http://dx.doi.org/10.3390/jimaging9010008.

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Hardness is one of the most important mechanical properties of materials, since it is used to estimate their quality and to determine their suitability for a particular application. One method of determining quality is the Vickers hardness test, in which the resistance to plastic deformation at the surface of the material is measured after applying force with an indenter. The hardness is measured from the sample image, which is a tedious, time-consuming, and prone to human error procedure. Therefore, in this work, a new automatic method based on image processing techniques is proposed, allowing for obtaining results quickly and more accurately even with high irregularities in the indentation mark. For the development and validation of the method, a set of microscopy images of samples indented with applied forces of 5N and 10N on AISI D2 steel with and without quenching, tempering heat treatment and samples coated with titanium niobium nitride (TiNbN) was used. The proposed method was implemented as a plugin of the ImageJ program, allowing for obtaining reproducible Vickers hardness results in an average time of 2.05 seconds with an accuracy of 98.3% and a maximum error of 4.5% with respect to the values obtained manually, used as a golden standard.

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Kim, Jong-Il, Yong-Hak Huh, and Yong-Hwan Kim. "Static Residual Tensile Strength Response of GFRP Composite Laminates Subjected to Low-Velocity Impact." Applied Sciences 10, no. 16 (August 7, 2020): 5480. http://dx.doi.org/10.3390/app10165480.

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The dependency of the static residual tensile strength for the Glass Fiber-Reinforced Plastic (GFRP) laminates after impact on the impact energy level and indent shape is investigated. In this study, two different laminates, unidirectional, [0°2]s) and TRI (tri-axial, (±45°/0°)2]s), were prepared using the vacuum infusion method, and an impact indent on the respective laminates was created at different energy levels with pyramidal and hemispherical impactors. Impact damage patterns, such as matrix cracking, delamination, debonding and fiber breakage, could be observed on the GFRP laminates by a scanning electron microscope (SEM), and it is found that those were dependent on the impactor head shape and laminate structure. Residual in-plane tensile strength of the impacted laminates was measured and the reduction of the strength is found to be dependent upon the impact damage patterns. Furthermore, in this study, stress concentrations in the vicinity of the indents were determined from full-field stress distribution obtained by three-dimensional Digital Image Correlation (3D DIC) measurement. It was found that the stress concentration was associated with the reduction of the residual strength for the GFRP laminates.

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DolatiAsl, Kianoush, Ehsan Abedini, and Younes Bakhshan. "Numerical investigation of the effect of bump and indent inside a vertical tube on the subcooled flow boiling and critical heat flux." Journal of Mechanical Engineering and Sciences 14, no. 2 (June 22, 2020): 6690–708. http://dx.doi.org/10.15282/jmes.14.2.2020.12.0524.

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One of the essential industry problems is the critical heat flux (CHF) phenomenon in the flow boiling regime which leads to the temperature jumping and damaging to the systems. Increasing the vapour volume fraction decreases the heat transfer coefficient, and finally, temperature jump will occur. Also, the existence of the bumps and indent in the flow domain changes the flow pattern. In this study, by considering bumps and indent in the tube, the boiling of fluid flow in the vertical tube is discussed. For modelling and simulating the problems, the Euler-Euler model for studying the interaction of the liquid-vapour phases was used. Some models and material specifications are declared using the user-defined function (UDF) codes to the ANSYS Fluent program. The results show that the existence of bumps and indent inside the tube causes the flow of liquid phase to be less redirected in comparison to vapour phase flow due to having more momentum; therefore, at the end of the bumps in the tube, the amount of vapour volume fraction near the wall rises sharply. By increasing the flow mass flux, the vapour volume fraction at the end of bumps increases which lead to decreasing CHF value. It has also observed that if there are bumps and indents inside the tube, there will be no significant change in the liquid flow and vapour volume fraction in the other parts of the tube, as compared to the regular tube.

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Salim, M. M., D. M. France, and C. B. Panchal. "Heat Transfer Enhancement on the Outer Surface of Spirally Indented Tubes." Journal of Enhanced Heat Transfer 6, no. 5 (1999): 327–41. http://dx.doi.org/10.1615/jenhheattransf.v6.i5.10.

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Panchal, C. B., and D. M. France. "Heat transfer and pressure drop in large pitch spirally indented tubes." International Journal of Heat and Mass Transfer 36, no. 3 (February 1993): 565–76. http://dx.doi.org/10.1016/0017-9310(93)80032-p.

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Usami, Hatsuhiko, Tomoya Kadomae, Daisuke Igimi, and Mineo Mizuno. "Effect of Indenter Materials on Indentation Fracture of Alumina Ceramics." Key Engineering Materials 290 (July 2005): 23–30. http://dx.doi.org/10.4028/www.scientific.net/kem.290.23.

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The present study describes the effect of indenter materials on Hertzian cracking behavior of alumina ceramics in sphere indentation. Numerical analysis (FEM) was carried out to investigate the influence of the frictional resistance at the interface due to the elastic mismatch between the indenter and the flat specimen on the stress distribution near the contact area. Two kinds of alumina ceramics with different mechanical properties were used for the flat specimen. Materials of the sphere indenter were cemented carbide, silicon nitride, alumina and hardened steel. The indenter was penetrated into the specimen with an electro-mechanical testing apparatus at a constant cross-head-speed in air. The indentation fracture was monitored with the acoustic emission signal. The numerical analysis revealed that the frictional resistance had influenced on the stress distribution. The experimental data showed that the ring crack radius, the crack pass below the contact zone and the indentation strength were different depending on the indenter material. From the comparison between the numerical analysis and the experimental data, it was found that the minimum value of the ring crack radius of the low density alumina flat specimen corresponds to the position of the maximum tensile stress.

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Jha, Rajesh, and Arvind Agarwal. "Software (GUI/APP) for Developing AI-Based Models Capable of Predicting Load-Displacement Curve and AFM Image during Nanoindentation." Coatings 11, no. 3 (March 5, 2021): 299. http://dx.doi.org/10.3390/coatings11030299.

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During nanoindentation tests, the load-displacement curve is used for estimating mechanical properties, while an indent image obtained through atomic force microscopy (AFM) is used for studying deformation of a material. We present a computational platform for developing artificial intelligence-based models for predicting indentation depth (load-displacement curve) and AFM image as a function of test parameters like maximum applied load, loading rate, and holding time. A user can directly use machine generated data in text (.txt) and hierarchical data format (HDF, hdf) format for developing the AI-based models for indentation depth and AFM image, respectively. The software was tested on three different coatings/materials for indentation depth: heat-treated (HT) sample of cold sprayed aluminum-based bulk metallic glass (Al-BMG) coating, carbon nanotube reinforced aluminum composite (Al-5CNT) coating, and spark-plasma-sintered hydroxyapatite (SPS HA) sample. For AFM imaging, a heat-treated (HT) sample of cold sprayed aluminum-based bulk metallic glass (Al-BMG) coating was considered. Correlation or R-values are close to 1 for all the models developed in this work. Predicted load-displacement curve and AFM image are in good agreement with the experimental findings. Our approach will be helpful in virtual simulation of load-displacement curves and AFM indent images for a large number of new test parameters, thus significantly reducing the number of indents needed for characterizing/analyzing a material.

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Kuznetsov, Viktor P., Andrei S. Skorobogatov, and V. G. Gorgots. "Mathematical Model of Thermal Physics of the Dual-Cycle Cooling System of the Tool for Pieces Nanostructuring Burnishing." Applied Mechanics and Materials 770 (June 2015): 449–55. http://dx.doi.org/10.4028/www.scientific.net/amm.770.449.

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The article considers the problems of the mathematical modeling of thermal physics of the tool for nanostructuring burnishing. Physical and equivalent heat diagram of the system are developed. On the basis of the equivalent heat transfer diagram, the equivalent circuit and the system of equations of the mathematical model are created. The dependence of the tool indenter tip temperature on cooling system thermal parameters is obtained. The comparison of efficiency of heat removal from the tool indenter when using the developed two-circuit cooling system and the system supplying lubricant cooling liquid through the lathe centre spindle, as well as when applying nanostructuring burnishing without cooling is carried out.

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25

Lee, Sang Chun, Sang Chul Nam, and Tae Gon Ban. "Performance of heat transfer and pressure drop in a spirally indented tube." KSME International Journal 12, no. 5 (September 1998): 917–25. http://dx.doi.org/10.1007/bf02945559.

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26

Johnson, Matthew, and John W. Bond. "Visualizing Indented Writing on Thermal Paper by the Controlled Application of Heat." Journal of Forensic Sciences 62, no. 5 (January 20, 2017): 1366–71. http://dx.doi.org/10.1111/1556-4029.13400.

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27

Malzbender, J., and R. W. Steinbrech. "Determination of the stress-dependent stiffness of plasma-sprayed thermal barrier coatings using depth-sensitive indentation." Journal of Materials Research 18, no. 8 (August 2003): 1975–84. http://dx.doi.org/10.1557/jmr.2003.0274.

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The elastic response of atmospheric plasma-sprayed coatings was investigated using Vickers and spherical indenter geometries. In both cases a strong dependency of the stiffness on the applied load (indentation depth) was observed. The stiffness of the coatings decreased with increasing load for a Vickers indenter, whereas it increased for a spherical indenter. This contrary behavior was related to the relative crack density in the deformed volume and to the stress dependence of the stiffness due to crack closure. The effect of annealing on the stiffness was quantified for both tip geometries. The heat treatment yielded additional information on the relationship between the indentation data and the microstructural defects. From the results it was concluded that the stiffness measured using a sharp indenter and small load reflected the elastic behavior of single spraying splats. With the relatively large spherical indenter, the average global stiffness of the thermal barrier coating was measured even at small loads. From the data obtained using the spherical indenter, a compressive stress–strain curve was suggested. Furthermore, values of the apparent crack density and yield strength were determined from the indentation tests.

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Zhang, J. Q., Atsunori Matsuda, Hiroyuki Muto, and Mototsugu Sakai. "Mechanical Properties of Sol-Gel Inorganic-Organic Hybrid Films in Nanoindentation." Key Engineering Materials 317-318 (August 2006): 317–22. http://dx.doi.org/10.4028/www.scientific.net/kem.317-318.317.

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Methylsilsesquioxane films were formed on glass substrates by dropping a sol prepared from methyltriethoxysilane and then heat-treated in an oven. Nanoindentation test was performed to assess the elastoplastic properties of the films, including the relative residual depth ξr, Meyer hardness HM, work-of-indentation WI and the elastic modulus E’. The values of ξr, HM and WI were obtained by a Berkovich indenter and E’ was determined by a spherical indenter on the basis of Hertz elastic theory. ξr decreased with the increase in the heat treatment time, whereas HM , WI and E’ significantly increased with the time. The changes in the mechanical properties with the heat treatment time well reflected the evolution of the Si-O-Si network structure in methylsilsequioxane film.

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29

Goshima, T., and L. M. Keer. "Thermoelastic Contact Between a Rolling Rigid Indenter and a Damaged Elastic Body." Journal of Tribology 112, no. 2 (April 1, 1990): 382–90. http://dx.doi.org/10.1115/1.2920268.

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The two-dimensional thermoelastic contact problem of a rolling, rigid cylinder on an elastic half space containing a surface-breaking crack is solved using complex variable techniques. The effects of heat generation and friction between the cylinder and half space and of friction and heat transfer on the faces of the crack are considered. The problem is reduced to a pair of singular integral equations which are solved numerically. Numerical results are obtained when the loading is a Hertzian distributed heat input. By consideration of combinations of parameters, stress intensity factors for which the crack is likely to grow are shown.

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Bunonyo, K., C. Israel-Cookey, and E. Amos. "MHD Oscillatory Flow of Jeffrey Fluid in an Indented Artery with Heat Source." Asian Research Journal of Mathematics 7, no. 4 (December 26, 2017): 1–13. http://dx.doi.org/10.9734/arjom/2017/37604.

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Lin, Yuan, and Timothy C. Ovaert. "Thermal Distortion of an Anisotropic Elastic Half-Plane and its Application in Contact Problems Including Frictional Heating." Journal of Tribology 128, no. 1 (September 16, 2005): 32–39. http://dx.doi.org/10.1115/1.2125907.

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The thermal surface distortion of an anisotropic elastic half-plane is studied using the extended version of Stroh’s formalism. In general, the curvature of the surface depends both on the local heat flux into the half-plane and the local temperature variation along the surface. However, if the material is orthotropic, the curvature of the surface depends only on the local heat flux into the half-plane. As a direct application, the two-dimensional thermoelastic contact problem of an indenter sliding against an orthotropic half-plane is considered. Two cases, where the indenter has either a flat or a parabolic profile, are studied in detail. Comparisons with other available results in the literature show that the present method is correct and accurate.

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Pakkratoke, Montree, Shinnosuke Hirata, Chisato Kanamori, and Hisayuki Aoyama. "Development of Microscopic Hardness and Stiffness Investigation System with Microrobot 2nd Report, Vision Based Precise Navigation." Journal of Robotics and Mechatronics 25, no. 1 (February 20, 2013): 97–105. http://dx.doi.org/10.20965/jrm.2013.p0097.

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A microsurface measurement system that is composed of the microrobot with the indenter and a vision based navigation system is proposed for investigating hardness and stiffness of such microparts. Here the tiny robot with the electromagnetic legs and the piezo elements incorporates with an electromagnetic driven microforce generator. This force generator can provide small forces up to 17 mN with 50 µN resolutions and push down the microindenter to the surface. The displacement of the indenter head can be also measured by the Linear Valuable Differential Transformer (LVDT) on machine. Thus, this mechanism can generate the small force and monitor the depth behaviour of the indenter during whole dwell time. Since the overall size of this mechanism is small enough to implement on the piezo-driven microrobot, the tiny robot with the microindenter is capable tomove precisely step by step with 1 µm per step so that the microindenter could be penetrated anywhere on the sample surface. With the help of an image processing technique, the vision based coordination system with the local close-up view and the overall global view has been developed to identify the locations of small robot and the indenter precisely within ±3 µm accuracy over the working range. In the experimental results, several results that the indentation load-depth characteristics of the unhealthy human tooth are measured automatically at the specified point are discussed.

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Salman, Mohammad, Myeong Hyeon Park, Ranchan Chauhan, and Sung Chul Kim. "Experimental analysis of single loop solar heat collector with jet impingement over indented dimples." Renewable Energy 169 (May 2021): 618–28. http://dx.doi.org/10.1016/j.renene.2021.01.043.

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34

Ogulu, A., and T. M. Abbey. "Simulation of heat transfer on an oscillatory blood flow in an indented porous artery." International Communications in Heat and Mass Transfer 32, no. 7 (July 2005): 983–89. http://dx.doi.org/10.1016/j.icheatmasstransfer.2004.08.028.

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35

Sukmana, Irza. "The Effect of Pin Shape on the Friction Stir Welding Quality of Aluminum AA1100 Series." Journal of Engineering and Scientific Research 4, no. 1 (June 28, 2022): 45–49. http://dx.doi.org/10.23960/jesr.v4i1.109.

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Aluminum is a material that is soft, lightweight, resistant to corrosion, and has good electrical and thermal conductivity. Aluminum has a specific gravity of about 2.65-2.8 kg/dm³, a melting point of 658ºC, and tensile strength of 90 MPa. Aluminum 1100 series is an aluminum alloy mixed with other materials, such as copper, iron, chrome, manganese, and zinc, with an aluminum content of 99,0%. Welding is the joining of two metals in a liquid state with or without filler. FSW (friction stir welding) is friction welding; the process does not require filler material. The heat used to melt the metal is obtained from the friction between the indenter and the workpiece. In the research, the shape of the indenter pin used is, ovale shape, cone shape, and changing spiral form with a tool rotation of 2000 rpm and a welding rate of 16 mm/minute. The tests carried out are Rockwell hardness testing and tensile tests. From the results of research conducted, it was found that the shape of the indenter pin greatly affects the quality of the weld. The indenter pin changing spiral form results in better weld quality compared to the other two pin shapes.

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36

Tarmizi, Tarmizi, and Odi Buana Hutapea. "Desain dan Pembuatan Perkakas untuk Proses Friction Stir Welding pada Material Aluminium 5052." Jurnal Riset Teknologi Industri 9, no. 2 (August 31, 2016): 107–19. http://dx.doi.org/10.26578/jrti.v9i2.1709.

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Friction Stir Welding is a process of joining metals without filler and without melting the base metal. The system uses the work of the FSW tool with a rotating cylindrical indenter to heat with friction material. Making tools for FSW process includes the selection of materials, testing the chemical composition, microstructure, tool design, heat treatment process on the tool, and testing tools. Materials used tool steel AISI H13 or SKD 61. This steel has a combination of strength, wear resistance, and excellent toughness. The shape of the pin tool is to use triangles, cylinders, and cones. Tool is heated at a temperature of 1100oC on hold for 30 minutes, cooled in oil. Then the material is heated at a temperature of 450oC back on hold 30 minutes, cooled in the furnace has been turned off. Hardness test results produced after heat treatment at 52.8 HRC. The microstructure after heat treatment are carbide and martensite phase. In the experiments showed that the optimum welding on cylindrical shape with a visual tool welds excellent.ABSTRAKPengelasan aduk friksi (Friction Stir Welding) merupakan proses penyambungan logam tanpa logam pengisi dan tanpa melelehkan logam induk. Sistem kerja dari FSW menggunakan peralatan silindris yang berputar (rotating cylindrical tool) dengan indentor untuk memanaskan material dengan gesekan. Pembuatan peralatan untuk proses FSW ini meliputi pemilihan bahan material, pengujian komposisi kimia, struktur mikro, mendesain perkakas, proses perlakuan panas pada perkakas, dan pengujian pada perkakas. Material perkakas yang digunakan baja AISI H13 atau SKD 61. Baja ini memiliki kombinasi kekuatan, ketahanan aus, dan ketangguhan yang sangat baik. Bentuk pin perkakas yang gunakan ialah segitiga, silinder, dan kerucut. Perkakas dipanaskan pada temperatur 1100oC ditahan selama 30 menit, didinginkan di oli. Kemudian material dipanaskan kembali pada temperatur 450oC ditahan 30 menit, didinginkan dalam tungku yang telah dimatikan. Hasil uji kekerasan yang dihasilkan setelah perlakuan panas sebesar 52,8 HRC. Struktur mikro setelah perlakuan panas terdapat karbida dan fasa martensit. Pada percobaan pengelasan didapatkan hasil yang optimum pada bentuk peralatan silinder dengan visual lasan yang sangat baik. Kata kunci : Perkakas FSW, baja perkakas AISI H13, karbida krom

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Squires, M. C., J. Latimer, R. D. Adams, and C. G. Maher. "Indenter head area and testing frequency effects on posteroanterior lumbar stiffness and subjects' rated comfort." Manual Therapy 6, no. 1 (February 2001): 40–47. http://dx.doi.org/10.1054/math.2000.0379.

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38

Vansse, Olivier, Ute Kutschera, Béatrice Legendre, and Frédéric Osterstock. "Quantitative Approach of the Effective Coefficient of Heat Transfer During Quenching Vickers Indented Ceramic Samples." Key Engineering Materials 132-136 (April 1997): 607–10. http://dx.doi.org/10.4028/www.scientific.net/kem.132-136.607.

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Umesh, V., S. Bala Vignesh, and B. Raja. "A Study on Nucleate Boiling Heat Transfer Characteristics of Acetone on Smooth and Indented Surfaces." Experimental Heat Transfer 29, no. 3 (April 2015): 414–25. http://dx.doi.org/10.1080/08916152.2015.1012570.

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40

Dong, Z. F., and M. A. Ebadian. "Convective heat transfer in the entrance region of a rectangular duct with two indented sides." Computational Mechanics 8, no. 4 (1991): 269–78. http://dx.doi.org/10.1007/bf00577380.

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41

Mareš, V., and J. Blahovec. "Variation of the tree ring micro-hardness demonstrated on spruce wood." Journal of Forest Science 50, No. 3 (January 11, 2012): 135–41. http://dx.doi.org/10.17221/4608-jfs.

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Micro-hardness was used for the study of wood structure (Norway spruce) in the line perpendicular to tree rings (radial surface). The steel indentor 0.25 mm in diameter with flat head was used for this purpose. The individual penetration tests were performed at constant velocity 0.0167 mm/sinto a depth of 0.3 mm. Local wood strength was defined as the mean pressure on the indentor head at 0.02 mm penetration. The set of tests (~ 320) gave information about stress variation in dependence on the location of the test place in the tested surface. The stress was understood as a parameter describing the growth properties of wood similarly like the density usually used in dendrochronology. The measured strength variation is in agreement with visually observed tree rings. The acquired data made it possible to determine the mean characteristic points of the tree ring as well as the development of the parameters in dependence on the weather variations.

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42

Montanari, Roberto, and Alessandra Varone. "Flat-Top Cylinder Indenter for Mechanical Characterization: A Report of Industrial Applications." Materials 14, no. 7 (April 1, 2021): 1742. http://dx.doi.org/10.3390/ma14071742.

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FIMEC (flat-top cylinder indenter for mechanical characterisation) is an instrumented indentation test employing a cylindrical punch. It has been used to determine the mechanical properties of metallic materials in several applications of industrial interest. This work briefly describes the technique and the theory of indentation with a flat-ended punch. The flat indentation of metals has been investigated through experimental tests, and an equation has been derived to calculate the yield stress from the experimental data in deep indentation. The approach is supported by many data on various metals and alloys. Some selected case studies are presented in the paper: (i) crank manufacturing through pin squeeze casting; (ii) the evaluation of the local mechanical properties in a carter of complex geometry; (iii) the qualification of Al billets for extrusion; (iv) stress–relaxation tests on CuCrZr heat sinks; (v) the characterization of thick W coatings on CuCrZr alloy; (vi) the measure of the local mechanical properties of the molten-zone (MZ) and the heat-affected zone (HAZ) in welded joints. The case studies demonstrate the great versatility of the FIMEC test which provides information not available by employing conventional experimental techniques such as tensile, bending, and hardness tests. On the basis of theoretical knowledge and large amount of experimental data, FIMEC has become a mature technique for application on a large scale in industrial practice.

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CHOLLACOOP, NUWONG, and UPADRASTA RAMAMURTY. "THREE-DIMENSIONAL SIMULATION OF DEFORMATION FIELDS UNDERNEATH VICKERS INDENTER: EFFECTS OF POWER-LAW PLASTICITY." International Journal of Modern Physics B 24, no. 01n02 (January 20, 2010): 238–46. http://dx.doi.org/10.1142/s0217979210064174.

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The effects of power-law plasticity (yield strength and strain hardening exponent) on the plastic strain distribution underneath a Vickers indenter was systematically investigated by recourse to three-dimensional finite element analysis, motivated by the experimental macro- and micro-indentation on heat-treated Al - Zn - Mg alloy. For meaningful comparison between simulated and experimental results, the experimental heat treatment was carefully designed such that Al alloy achieve similar yield strength with different strain hardening exponent, and vice versa. On the other hand, full 3D simulation of Vickers indentation was conducted to capture subsurface strain distribution. Subtle differences and similarities were discussed based on the strain field shape, size and magnitude for the isolated effect of yield strength and strain hardening exponent.

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Dinh Vu, Huy, and Makoto Nanko. "Self-Healing Behavior of Y₂SiO₅ Toughened by SiC Particles." Key Engineering Materials 728 (January 2017): 149–54. http://dx.doi.org/10.4028/www.scientific.net/kem.728.149.

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Crack-healing effectiveness of Y2SiO5-based composites dispersed with 5 vol% SiC particles was investigated. Dense specimens of 5 vol% SiC/Y2SiO5 were fabricated by pulsed electric current sintering technique. Surface cracks were introduced by using a Vickers indenter to be a crack length of approximately 200 μm. Self-healing performance of SiC/Y2SiO5 composites via high-temperature oxidation in air was studied as a function of heat treatment temperature. As a result, surface cracks disappeared perfectly after heat treatment at 1300°C for 6 h in air.

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Pakkratoke, Montree, Shinnosuke Hirata, Chisato Kanamori, and Hisayuki Aoyama. "Development of Microscopic Hardness and Stiffness Investigation System with MicroRobot." Journal of Robotics and Mechatronics 24, no. 1 (February 20, 2012): 123–32. http://dx.doi.org/10.20965/jrm.2012.p0123.

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In order to investigate micro hardness and stiffness in a special chamber, the development of a small-force generator mechanism and a piezodriven microrobot is described in this paper. This small-force generator is simply composed of a Voice Coil Actuator (VCA) and the tandem leaf spring mechanism. The small force can be controlled by an electrical current, which is supplied to the coil and positioned precisely at the balance point with the parallel leaf spring with no mechanical friction. The full bridge strain gauges on both sides of the double leaf spring can detect a small force that is applied to the sample with a microindenter. This handmade small device can produce and verify small forces up to 17 mN with good linearity and a 50 µN resolution. The displacement of the indenter head can be also measured by the Linear Valuable Differential Transformer (LVDT) on the machine for monitoring the depth behavior of the indenter during the whole dwell time. The small force generator with the indenter can be implemented on the piezodriven microrobot to check the microscopic hardness and stiffness. This microrobot can move around the measurement area precisely step by step with 1 µm steps on a metal plate, so that the sample can be scanned with microscopic resolution in situ, such as in an SEM chamber. In the experiment results, the basic performance of microelasticity investigations with a certified hardness block was successfully checked and the indentation load-depth characteristics were precisely acquired on the path of the microrobot.

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Angella, Giuliano, Alessandra Fava, Roberto Montanari, Maria Richetta, and Alessandra Varone. "Flat-Top Cylinder Indenter Examination of Duplex Stainless Steel 2205 after Different Heat Treatments." Metals 7, no. 5 (May 17, 2017): 178. http://dx.doi.org/10.3390/met7050178.

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Hu, Jun Feng, Shi Jie Zhu, Wen Xue Wang, and Yukiko Nakahara. "Crack Healing Behavior of SiC Whisker Reinforced Si₃N₄ Composite." Materials Science Forum 750 (March 2013): 15–18. http://dx.doi.org/10.4028/www.scientific.net/msf.750.15.

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SiC whisker reinforced Si3N4 composite was used for studying crack healing behavior. Surface crack and straight-through crack were introduced on the tensile surface of specimens by Vickers hardness indenter and single edge pre-crack beam method. The cracked specimens were heat-treated at 1000 , 1100 , 1200 and 1300 for 1 hour in air. Bending strength was measured at room temperature by three point bending tests system. It was investigated that the best heat treatment temperature of Si3N4/SiC whisker composite is 1200 -1300 . The relationship between bending strength and logarithm of crack area was near linear and parabola in original and heat-treated specimens, respectively. Crack healing behavior was analyzed by oxidation filling model according to oxidation kinetics.

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Bérces, G., J. Lendvai, A. Juhász, and N. Q. Chinh. "Dynamic characterization of Portevin–Le Chatelier instabilities occurring in depth-sensing microhardness tests." Journal of Materials Research 18, no. 12 (December 2003): 2874–81. http://dx.doi.org/10.1557/jmr.2003.0401.

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Characteristic properties of plastic instabilities were studied using depth-sensing microhardness experiments on an Al–3.3 wt.% Mg alloy and computer simulations based on a macroscopic dynamic model of the experimental setup. A stepwise increase was observed in the indentation depth versus load (d-F) curves measured in constant loading rate mode, indicating hardness oscillations around a nearly constant value of the conventional dynamic microhardness. These oscillations were correlated with plastic instabilities starting from the contact surface between the sample and the indenter head. Taking into account the experimentally determined connection between the hardness oscillations and the indentation velocity, a dynamic model was proposed for the characterization of instability steps.

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Marsan, Anne L., Yifan Chen, and Paul J. Stewart. "Surface Feature Parametrization Analogous to Conductive Heat Flow." Journal of Computing and Information Science in Engineering 2, no. 2 (June 1, 2002): 77–85. http://dx.doi.org/10.1115/1.1510860.

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Direct Surface Manipulation (DSM) allows a designer to add a raised or indented feature to an existing surface. The user bounds the feature with a closed curve, and defines an influence center that indicates the point or curve of maximum displacement from the original surface. As we move radially outward from the influence center to the boundary curve, the magnitude of displacement is scaled gradually by a one-dimensional polynomial basis function whose values range from 0 to 1. In this paper we present a new technique for assigning parameter values in the radial direction, i.e., u, to points within a DSM feature. The new technique poses parameter distribution as a steady state heat conduction problem and uses a finite element method to solve for ux,y. The new method overcomes some stringent geometric conditions inherited from a fundamentally geometric-based reparameterization scheme and allows us to work with non-star-shaped and multiply connected DSM features. Thus it allows us to apply this surface feature technique to a wider variety of surface applications.

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Baiocco, Gabriele, Daniele Almonti, Silvio Genna, Gennaro Salvatore Ponticelli, Vincenzo Tagliaferri, and Nadia Ucciardello. "Neural network implementation for the prediction of load curves of a flat head indenter on hot aluminum alloy." Procedia CIRP 88 (2020): 543–48. http://dx.doi.org/10.1016/j.procir.2020.05.094.

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Journal articles on the topic 'Indented Head'

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