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Academic literature on the topic 'Nitinol'

Author: Grafiati

Published: 4 June 2021

Last updated: 10 March 2023

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Journal articles on the topic "Nitinol"

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van Hai, Dinh, Hoang Minh Tam, and Duong van Quang. "Application of Finite Element Method to the Simulation of Vessel Stents." Materials Science Forum 804 (October 2014): 243–47. http://dx.doi.org/10.4028/www.scientific.net/msf.804.243.

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In this study, the effects of supereslasticity of Nitinol for self-expanding (SX) stents – Stent devices which are implanted into the blood vessels in order to restore blood flow in a diseased artery segment (narrowing of the blood vessel due to plaque build-up) and keep the artery open after angioplasty were considered and analyzed. To emphasize the unique properties of Nitinol as compared to other materials, this study was conducted to differentiate the behaviors of two types of stents which are made of Nititol and 316L stainless steel during implantation. Finite element analysis was used for simulation and modeling. The study results are expected to serve well the design of vessel stents.

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Kim, Jae Hoon, Jun Sik Son, Kwi Deok Park, Jong Man Kim, Jae Jin Kim, Kwang Duk Ahn, and Dong Keun Han. "Blood Compatibility of Novel Zwitterionic PEG-Grafted Nitinol Alloy for Peripheral Arterial Stents." Key Engineering Materials 342-343 (July 2007): 805–8. http://dx.doi.org/10.4028/www.scientific.net/kem.342-343.805.

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In this study, newly synthesized zwitterionic PEG was grafted on Nitinol alloy using oxidation treatment. The surface property and blood compatibility of surface-modified Nitinols were examined. The results of surface analysis showed that the contact angle and the ratio of oxygen to carbon significantly decreased with Nitinol alloys. The total amount of fibrinogen (0.095 μg/cm2) adsorbed onto TiNi-PEG2K-N+-S- was lower than that of TiNi control (0.12 μg/cm2). The platelet adhesion decreased in the order of TiNi control > TiNi-MPEG2K > TiNi-PEG2K-N+-S. Particularly, zwitterionic PEG with PEG2K was proven better than any others. The results indicated that zwitterionic PEG surface could significantly suppress platelet adhesion and protein adsorption as compared to other samples. The present study suggested that grafted zwitterionic PEG structure may possess improved blood compatibility.

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Rehman, Ateekh Ur, Nagumothu Kishore Babu, Mahesh Kumar Talari, Yusuf Usmani, and Hisham Alkhalefah. "Characterisation of Microstructure and Mechanical Properties of Linear Friction Welded α+β Titanium Alloy to Nitinol." Applied Sciences 11, no. 22 (November 12, 2021): 10680. http://dx.doi.org/10.3390/app112210680.

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A variable area nozzle integrated into the design of a high-bypass-ratio turbofan engine effectively saves up to 10% in aircraft fuel consumption. Additionally, noise emissions can be lowered at airports during take-off and landing by having better control of the nozzle diameter. Shape memory capabilities of Nitinol alloys could be availed in the form of actuators in the construction of such a nozzle. However, these Nitinol actuators must be joined to Ti-6Al-4V, a prominent alloy making up most of the rest of the nozzle. Because of the huge differences in the physical and metallurgical properties of these alloys, fusion welding is not as effective as solid-state welding. In the current study, a linear friction welding process was adopted to join Ti-6Al-4V to Nitinol successfully. The effect of friction welding on the evolution of weld macro and microstructures; hardness and tensile properties were studied and discussed. The macrostructure of Ti-6Al-4V and Nitinol’s dissimilar joint revealed flash formation mainly on the Ti-6Al-4V side due to its reduced flow strength at high temperatures. Optical microstructures revealed fine grains in Ti-6Al-4V immediately adjacent to the interface due to dynamic recrystallisation and strain hardening effects. In contrast, Nitinol remained mostly unaffected. An intermetallic compound (Ti2Ni) was seen to have formed at the interface due to the extreme rubbing action, and these adversely influenced the tensile strength and elongation values of the joints.

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HUSSAIN, SAJJAD, and QAISER KHAN. "NITINOL STENTS." Professional Medical Journal 18, no. 04 (December 10, 2011): 654–57. http://dx.doi.org/10.29309/tpmj/2011.18.04.2657.

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Stents deployed in the carotid arteries cause significant geometric changes in the vessels, influencing the flexibility and torsion characteristics of the vessels, which are aggravated by the high degree of mobility in this area of the body. The influence of these physical characteristics on carotid blood flow could influence the long term performance of the deployed stents. Objectives: To evaluate the geometric changes in the carotid arteries after deployment of self expanding nitinol stents. Settings: AFIC-NIHD. Period: November 2003 to August 2008. Material & methods: 45 cases of carotid artery stenting (CAS) done. We selected cases where the stenting to the internal carotid artery (ICA) had been done across the bifurcation of the common carotid artery (CCA) with self expanding nitinol stents, and when DICOM videos that had pre and post stenting images in the same imaging projection were available for analysis. Based on the inclusion criteria 21 videos were selected and deemed fit for taking measurements. The measurement system proposed by Berkefeld et al which involved the measurement of the CCA-ICA (common carotid artery –internal carotid artery) angle and ICA-offset was used. These variables were measured using onscreen measuring software which can measure linear distances and angles after appropriate calibration for each image. Results: We did not find any significant changes in the ICA-offset; significant changes in the CCA-ICA angle were noted.

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Tobushi, H., and J. R. Gahoon. "Mechanical Analysis of a Solar-Powered Solid State Engine." Transactions of the Canadian Society for Mechanical Engineering 9, no. 3 (September 1985): 137–41. http://dx.doi.org/10.1139/tcsme-1985-0020.

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The mechanical principle of a solar-powered solid state engine utilizing the shape-memory effect is analyzed. The performance of a differential pulley Nitinol engine is discussed and it is calculated that a small, solar-powered differential pulley Nitinol engine could produce up to 15W with a single Nitinol wire, A higher power solar Nitinol engine producing up to 15 kW is possible by using larger Nitinol wire, and over 1 MW may be expected by applying the higher power engine system. The size of the solar energy collector needed to generate mechanical energy via a Nitinol engine is estimated to be about 0.02 m2/W and the total efficiency of the engine predicted to be about 4%, The overall efficiency and economics of a solar-powered Nitinol engine should be in the same order as that of solar energy system utilizing the photovoltaic effect.

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Schipper, Oliver N., Samuel E. Ford, Patrick W. Moody, Bryce Van Doren, and J. Kent Ellington. "Radiographic Results of Nitinol Compression Staples for Hindfoot and Midfoot Arthrodeses." Foot & Ankle International 39, no. 2 (October 27, 2017): 172–79. http://dx.doi.org/10.1177/1071100717737740.

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Background: The purpose of this study was to determine the radiographic union rate after midfoot and hindfoot arthrodeses using a new generation of nitinol staples, and to compare outcomes between a nitinol staple construct and a nitinol staple and threaded compression screw construct. Methods: A retrospective chart review was performed to identify patients who underwent hindfoot or midfoot arthrodesis using a new generation of nitinol compression staples with or without a partially threaded cannulated screw with minimum 3-month radiographic follow-up. The primary outcome variable was radiographic evidence of arthrodesis on radiographs and, when available, computed tomographic scan in patients who underwent midfoot or hindfoot arthrodesis using nitinol staples. Ninety-six patients and 149 joints were eligible for analysis. Median radiographic follow-up was 5.7 months. Results: Radiographic union was seen in 93.8% (60/64) of patients and 95.1% (98/103) of joints using the nitinol staple construct. Radiographic union was seen in 90.6% (29/32) of patients and 95.7% (44/46) of joints using the nitinol combined staple and screw construct. There was no significant difference in radiographic union rate or revision surgery between the 2 groups. Seven patients developed nonunion, 4 in the nitinol staple construct group and 3 in the staple and screw group. Conclusions: New-generation nitinol staples were safe and effective for hindfoot and midfoot arthrodeses, with a high radiographic union rate. The use of a partially threaded screw for additional fixation was not found to either significantly increase or decrease radiographic fusion with nitinol staple fixation. Level of Evidence: Level III, comparative cohort study.

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Wang, Zheng Pin, Jian Lu Ma, Yu Hong Yao, Jiang Nan Liu, Wei Gao, and Yao Hua Jin. "Properties of Self-Expanding Nitinol Stents Treated by Addition of 600°C Heat Setting Process." Advanced Materials Research 239-242 (May 2011): 2206–9. http://dx.doi.org/10.4028/www.scientific.net/amr.239-242.2206.

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For its two unique properties of superelasticity and shape memory, nitinol is widely used in medical applications. Traditionally, most nitinol stents are normally heat set at 485°C, which induces the formation of the Ni-rich second phases such as Ti2Ni3 and Ti3Ni4, increases the austenite finish temperature and reduces material strength and fatigue performance. The addition of 600°C heat setting was applied to the nitinol stents after 485°C heat setting process and its effect on the mechanical, dimensional and functional properties of the nitinol stents were investigated. The experimental results showed that the nitinol stent tubes with the addition of 600°C heat setting process had higher elastic modulus, ultimate tensile strength, elongation percentage, inner dimension and outer dimension than those of the nitinol stents with 485°C heat setting process. Moreover, after the addition of 600°C expansion step, the nitinol stents almost had the same average deployment force and deployment accuracy as those of the nitinol stents with 485°C heat setting process and higher average inner dimension (ID) and outer dimension than that of those without the 600°C expansion step. Either treated with the addition of 600°C heat setting process or only 485°C heat setting process, the average austenite finish temperature (Af ) of the nitinol stents was both lower than the body temperature and the average Af of the fomer was 8°C lower than that of the latter.

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Maksymova, S. V., and B. V. Stefaniv. "Producing nitinol brazed joints (Review)." Paton Welding Journal 2022, no. 12 (December 28, 2022): 19–28. http://dx.doi.org/10.37434/tpwj2022.12.03.

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Galimzyanov, Bulat N., and Anatolii V. Mokshin. "Amorphous Porous Phase of Nitinol Generated by Ultrafast Isobaric Cooling." Solid State Phenomena 310 (September 2020): 150–55. http://dx.doi.org/10.4028/www.scientific.net/ssp.310.150.

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Titanium nickelide (nitinol) is of great applied interest in various industries due to unique combination of its physical and mechanical characteristics. In the present work, we consider the possibility of obtaining nitinol with mesoporous structure by rapidly cooling the molten sample to room temperature. Based on molecular dynamics simulation data, it was shown that the rapid cooling of the nitinol melt leads to formation of a porous structure. It was shown that the inner pore wall is formed mainly by titanium atoms, which provide biocompatibility of nitinol. It was found that the porosity of nitinol weakly depends on the cooling rate, while the porosity increases linearly with decreasing melt density.

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McCummiskey, Emma, William M. Dempster, D. H. Nash, T. R. Ashton, and D. G. Stevenson. "The Determination and Evaluation of Nitinol Constitutive Models for Finite Element Analysis." Applied Mechanics and Materials 7-8 (August 2007): 81–88. http://dx.doi.org/10.4028/www.scientific.net/amm.7-8.81.

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Superelastic Ni-Ti (Nitinol) is a member of the shape memory alloy (SMA) family of metals. The physical properties of Nitinol are highly dependant on a number of factors, including manufacturing method, subsequent processing, operating temperature, and strain rate. These factors complicate the prescription of material constitutive models, leading to complexities in the computational analysis of Nitinol components. The current work explores the limitations in the Nitinol material model available in existing commercial finite element (FE) software using a series of specially design experimental tests and representative FE models.

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Dissertations / Theses on the topic "Nitinol"

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Mizar, Shivananda Pai. "Thermomechanical characterization of NiTiNOL and NiTiNOL based structures using ACES methodology." Link to electronic thesis, 2005. http://www.wpi.edu/Pubs/ETD/Available/etd-021606-104515/.

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Mizar, Shivananda Pai. "Thermomechanical characterization of NiTiNOL and NiTiNOL based structures using ACES methodology." Digital WPI, 2006. https://digitalcommons.wpi.edu/etd-dissertations/61.

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Recent advances in materials engineering have given rise to a new class of materials known as active materials. These materials when used appropriately can aid in development of smart structural systems. Smart structural systems are adaptive in nature and can be utilized in applications that are subject to time varying loads such as aircraft wings, structures exposed to earthquakes, electrical interconnections, biomedical applications, and many more. Materials such as piezoelectric crystals, electrorheological fluids, and shape memory alloys (SMAs) constitute some of the active materials that have the innate ability to response to a load by either changing phase (e.g., liquid to solid), and recovering deformation. Active materials when combined with conventional materials (passive materials) such as polymers, stainless steel, and aluminum, can result in the development of smart structural systems (SSS). This Dissertation focuses on characterization of SMAs and structures that incorporate SMAs. This characterization is based on a hybrid analytical, computational, and experimental solutions (ACES) methodology. SMAs have a unique ability to recover extensive amounts of deformation (up to 8% strain). NiTiNOL (NOL: Naval Ordinance Lab) is the most commonly used commercially available SMA and is used in this Dissertation. NiTiNOL undergoes a solid-solid phase transformation from a low temperature phase (Martensite) to a high temperature phase (Austenite). This phase transformation is complete at a critical temperature known as the transformation temperature (TT). The low temperature phase is softer than the high temperature phase (Martensite is four times softer than Austenite). In this Dissertation, use of NiTiNOL in representative engineering applications is investigated. Today, the NiTiNOL is either in ribbon form (rectangular in cross-section) or thin sheets. In this Dissertation, NiTiNOL is embedded in parent materials, and the effect of incorporating the SMA on the dynamic behavior of the composite are studied. In addition, dynamics of thin sheet SMA is also investigated. The characterization is conducted using state-of-the- art (SOTA) ACES methodology. The ACES methodology facilitates obtaining an optimal solution that may otherwise be difficult, or even impossible, to obtain using only either an analytical, or a computational, or an experimental solution alone. For analytical solutions energy based methods are used. For computational solutions finite element method (FEM) are used. For experimental solutions time-average optoelectronic holography (OEH) and stroboscopic interferometry (SI) are used. The major contributions of this Dissertation are: 1. Temperature dependent material properties (e.g., modulus of elasticity) of NiTiNOL based on OEH measurements. 2. Thermomechanical response of representative composite materials that incorporate NiTiNOL“fibers". The Dissertation focuses on thermomechanical characterization of NiTiNOL and representative structures based on NiTiNOL; this type of an evaluation is essential in gainfully employing these materials in engineering designs.

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Garcia, Angelo. "Control of nitinol wire actuator." Thesis, University of Canterbury. Mechanical Engineering, 2003. http://hdl.handle.net/10092/6610.

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The Stewart Platform is well known parallel robotic mechanism often used for flight simulators. Less well known applications involve robotics and machine tools. This research deals with Stewart Platforms that use Nitinol wire, a shape memory alloy, as binary actuators that are switched on and off to control the position of the platform. Binary control of the six actuators on a platform yields sixty four possible platform positions, and four stacked platforms yield 256E12 possible positions. The design of a simple basic four stages model is described in this research. Experiments were conducted on the Nitinol wire to investigate the shape memory effects, hysteresis and the martensite/austenite phase transformations. These results were used in the design of a high power to weight ratio Stewart Platform, overcoming many of the drawbacks of previous models that are powered by heavy hydraulics or electric motors. Due to the complexity of some of the parts and small numbers required, rapid prototyping was used to manufacture over 90% of the structure. In this research, the control system proposed is expected to be useful for not only Shape Memory Alloy (SMA) actuators but also other actuators with hysteresis, for example, piezoceramic actuators, rubber actuators driven by air supply, bellows actuators, etc.

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Di, Leo Claudio V. "Nitinol-reinforced shape-memory polymers." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/59905.

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Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 33).
Reinforced shape-memory polymers have been developed from an acrylate based thermoset shape-memory polymer and nitinol wires. A rectangular shape-memory polymer measuring approximately 1 by 2 by 0.1 inches has a ten fold increase in actuation force under three-point bending when reinforced with two 0.02 inch diameter nitinol wires. A constitutive model for shape-memory polymers and nitinol has been used to predict with good correlation the actuation-versus-time and displacement-versustime behavior of the reinforced shape-memory polymer composites. It is possible then, using finite-element modeling, to design and manufacture reinforced shape-memory polymers tailored for use as thermally-activated actuators of specific force.
by Claudio V. Di Leo.
S.B.

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McCarty, David Hughes Mary Leigh. "Durability of nitinol for structural applications." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Summer/Theses/MCCARTY_DAVID_39.pdf.

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Shayanfard, Pejman. "Role of Plasticity in Nitinol Fatigue." Doctoral thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2021. http://www.nusl.cz/ntk/nusl-438772.

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Disertace analyzuje vliv koncentrátorů napětí na průběh martensitické transformace, vznik plastické deformace a její vliv na přerozdělení napětí a vznik zbytkového pnutí a reziduálního martenzitu v okolí koncentrátorů v prvcích ze slitin s tvarovou pamětí NiTi. Vliv je analyzován v režimech superelastického isotermálního cyklování a aktuačního cyklování, t.j. teplotního cyklování pod vnějším napětím. Disertace využívá pro vyhodnocení vlivu experimentální přístup spolu s numerickými simulacemi metodou konečných prvků na modelových případech tenkých pásků ze slitin NiTi opatřených půlkruhovými vruby. V experimentální části je vyhodnocován vliv koncentrátorů pomocí termomechanických experimentů s využitím metod obrazové korelace a rentgenové mikrodifrakce pro lokální analýzu deformací a fázových objemových podílů v průběhu cyklování v okolí vrubů. Simulace metodou konečných prvků poskytují komplementární informace o průběhu napětí, deformací a martensitické transformaci, zejména o vývoji jednotlivých složek celkové deformace, tj. elastické a plastické, a vývoji zbytkového pnutí a s ním souvisejícím zbytkovým martensitem.Disertace je dále doplněna o numerickou analýzu vlivu konstrukce stentů na lokální cyklický průběh martensitické transformace a jeho vliv na únavové vlastnosti.

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Huß, Niklas [Verfasser]. "Endoskopische Lungenvolumenreduktion mittels Nitinol Coils / Niklas Huß." Saarbrücken : Saarländische Universitäts- und Landesbibliothek, 2019. http://d-nb.info/1222973804/34.

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Feeney, Andrew. "Nitinol cymbal transducers for tuneable ultrasonic devices." Thesis, University of Glasgow, 2014. http://theses.gla.ac.uk/5805/.

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In recent years, there has been notable interest in the integration of smart and active materials, such as shape memory alloys, in the design of tuneable and multiple frequency devices. There is a growing desire to be able to tune transducers for a range of applications. As an example, surgical procedures could be enhanced by using an ultrasonic device whose performance could be tailored to penetrate more than one material, such as bone and soft tissue. Research conducted on cymbal transducers, a type of Class V flextensional transducer developed at Pennsylvania State University in the early 1990s, has been largely limited to low power applications, such as for hydrophone systems, and their performance in high power applications has only recently been studied. As such, the integration of smart materials to expand the useful applications of this type of transducer has not been fully explored. In this investigation, a shape memory alloy (SMA) called nickel-titanium, or Nitinol, has been adopted in two forms, one being superelastic and the other shape memory, as the end-cap material in the classical cymbal transducer configuration. The resonant frequencies of these transducers can be tuned by changes to the temperature of the Nitinol, which alters the microstructure, and the modulus, of the material. The microstructure of Nitinol can also be controlled by changes in applied stress. The phases present in the Nitinol microstructure are relatively hard cubic austenite and comparably soft monoclinic martensite. An intermediate phase, called the R-phase, can also appear. This is a rhombohedral distortion of austenite, and has been known to be a source of inconvenience for those who wish to avoid multiple stage transformations. An advantage of using Nitinol end-caps in the classical cymbal transducer configuration is that they are very small, hence minimal thermal energy is required to generate a phase transformation. Also, cymbal transducers are very simple and inexpensive to fabricate. The first part of this research focuses on the development of a dual resonance cymbal transducer using steel and titanium as the end-cap materials. Dynamic analysis techniques comprising electrical impedance measurements, experimental modal analysis (EMA) and vibration resonance response characterisation (VRRC) using laser Doppler vibrometry are introduced and form the dynamic characterisation process. The experimental data is supported in part by finite element analysis (FEA). It is demonstrated that a major problem in cymbal transducer fabrication is the difficulty in controlling the deposition of epoxy resin which is used to create the mechanical coupling in the transducer. This means that the bond layers in a transducer will likely be dissimilar, thereby introducing asymmetry into the transducer. This asymmetry can contribute to the dual resonance in a cymbal transducer. The cymbal transducer is designed to be actively tuneable by the incorporation of Nitinol end-caps in the transducer assembly. The characterisation of Nitinol transducers is performed using the dynamic characterisation methods in conjunction with differential scanning calorimetry (DSC). This is a thermoanalytical technique which has been adopted to estimate the transformation temperatures of Nitinol, and hence the temperatures at which each transducer must be driven to generate the desired operating frequencies. It is demonstrated that in certain cases, particularly with respect to superelastic Nitinol, the estimations of the transformation temperatures from the DSC analysis of Nitinol can be misinterpreted. The dynamic performance of Nitinol vibrating at ultrasonic frequencies has not before been the subject of detailed investigation, including the influence of superelasticity on the vibration response of an ultrasonic transducer. Superelasticity occurs in the austenite phase of Nitinol, where austenite reorients to martensite after a characteristic stress threshold is passed, thereby accommodating very large strains. The results show that whilst Nitinol can be used to fabricate cymbal transducers with tuneable resonant frequencies, there is no evidence that superelasticity contributes to the vibration response of the transducers. The incorporation of shape memory Nitinol in a simple prototype actuator device is also considered, where it appears that the transformation of the shape memory Nitinol is affected by the affixed cylinders used to create the device.

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Karjalainen, T. (Teemu). "Nitinol shape memory alloy in flexor tendon repair." Doctoral thesis, Oulun yliopisto, 2012. http://urn.fi/urn:isbn:9789514299803.

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Abstract Early motion is crucial for tendon healing and functional results after flexor tendon repair in the fingers. Motion, however, causes stress in the repair site, which can result in failure of the repair. A flexor tendon repair is made with fine calibre sutures, which sets exceptional requirements for the suture materials used in flexor tendon repair. Nitinol (nickel-titanium alloy) is a shape memory alloy, which can exist in two temperature-dependent forms, soft martensite and stiff austenite. It is possible to fabricate a nitinol wire that is soft and pliable, yet has high tensile strength. It also has excellent biocompatibility. Therefore, it is a potential candidate flexor tendon repair suture material. This study evaluates biomechanical aspects of martensite nitinol wire as a flexor tendon repair suture material. The study hypothesis was that nitinol wire improves the strength of the repairs compared with the repairs made with conventional suture materials. It was found that nitinol core repairs and circumferential repairs performed significantly better when compared with repairs made with commonly used braided polyester and polypropylene of equal calibre. To further optimise the performance of the nitinol wire in tendon surgery, two experimental models were developed to study the suture-tendon interface. The aim was to prevent pull-out of the suture loop so that surgeons could have full advantage of the tensile strength of the nitinol suture. First, it was tested whether it is possible to improve the suture’s ability to grip the tendon tissue by changing the suture type from monofilament to multifilament. Multifilament suture loops reached higher pull-out strength when compared with round monofilament loops when a locking loop was used. Subsequently, the grip of four different previously reported core repair loops was tested. Based on their failure mechanism, two novel loops were developed. The novel loops demonstrated superior ability to grip the tendon. The novel loops can be useful with high tensile strength suture materials and in repairs, which are prone to suture pull-out
Tiivistelmä Varhainen korjauksen jälkeinen aktiivinen kuntoutus on osoittautunut hyödylliseksi jänteen paranemiselle. Varhainen liike altistaa korjauksen kuormitukselle, joka voi johtaa korjauksen pettämiseen. Korjaukset tehdään ohuilla langoilla. Tämä asettaa erityisiä vaatimuksia jännekorjauksessa käytettävälle ommelainemateriaalille. Nikkeli-titaani (nitinoli) on nk. muistimetalli. Sillä on kaksi lämpötilariippuvaista muotoa: pehmeä martensiitti ja jäykkä austeniitti. Nitinolista voidaan valmistaa ohutta pehmeää ja taipuisaa lankaa, jonka vetolujuus on suuri. Nitinolin siedettävyys jännekudoksessa on todettu hyväksi, minkä vuoksi se on lupaava materiaali käytettäväksi jännekorjauksissa. Tässä tutkimuksessa kokeiltiin martensiittisen nitinolilangan käyttöä jänteen ydinompeleena ja pintaompeleena. Olettamuksena oli, että nitinolilangalla saadaan kestävämpiä korjauksia kuin nykyään käytössä olevilla langoilla. Tulosten mukaan nitinolilangalla tehdyt korjaukset olivat kestävämpiä, kun niitä verrattiin saman paksuiseen punottuun polyesteriin ja polypropyleeniin. Lisäksi kehitimme kaksi mallia, joiden tarkoituksena oli parantaa nitinolilankasilmukan pitoa jännekudoksesta. Tarkoituksena oli löytää keinoja, joilla langan otetta jännekudoksesta voidaan parantaa ja langan hyvät vetolujuusominaisuudet pääsevät oikeuksiinsa. Ensin muutimme langan muotoa perinteisestä yksisäikeisestä pyöreästä monisäikeiseen muotoon. Monisäikeisen langan läpileikkausvoima oli huomattavasti suurempi kuin yksisäikeisen pyöreän langan. Ero oli havaittavissa vain, kun käytettiin lukitsevaa silmukkaa. Tämän jälkeen testasimme neljän perinteisesti käytetyn korjaustekniikan silmukan pitokykyä ja tulosten perusteella kehitimme kaksi uutta silmukkaa. Työssä kehitetyt silmukat pitivät kiinni jänteestä huomattavasti paremmin kuin perinteiset silmukat. Työssä kehitetyillä silmukoilla voidaan optimoida vahvojen ommelainemateriaalien suorituskyky jännekirurgiassa

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Pulletikurthi, Chandan. "Biocompatibility Assessment of Biosorbable Polymer Coated Nitinol Alloys." FIU Digital Commons, 2014. http://digitalcommons.fiu.edu/etd/1552.

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Owing to an increased risk of aging population and a higher incidence of coronary artery disease (CAD), there is a need for more reliable and safer treatments. Numerous varieties of durable polymer-coated drug eluting stents (DES) are available in the market in order to mitigate in-stent restenosis. However, there are certain issues regarding their usage such as delayed arterial healing, thrombosis, inflammation, toxic corrosion by-products, mechanical stability and degradation. As a result, significant amount of research has to be devoted to the improvement of biodegradable polymer-coated implant materials in an effort to enhance their bioactive response. In this investigation, magneto-electropolished (MEP) and a novel biodegradable polymer coated ternary Nitinol alloys, NiTiTa and NiTiCr were prepared to study their bio and hemocompatibility properties. The initial interaction of a biomaterial with its surroundings is dependent on its surface characteristics such as, composition, corrosion resistance, work of adhesion and morphology. In-vitro corrosion tests such as potentiodynamic polarization and electrochemical impedance spectroscopic (EIS) studies were conducted to determine the coating stability and longevity. In-vitro hemocompatibility studies and HUVEC cell growth was performed to determine their thrombogenic and biocompatibility properties. Critical delamination load of the polymer coated Nitinol alloys was determined using Nano-scratch analysis. Sulforhodamine B (SRB) assays were performed to elucidate the effect of metal ions leached from Nitinol alloys on the viability of HUVEC cells. Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), contact angle meter and X-ray diffraction (XRD) were used to characterize the surface of the alloys. MEP treated and polymer coated (PC) Nitinol alloys displayed a corrosion resistant polymer coating as compared to uncoated alloys. MEP and PC has resulted in reduced Ni and Cr ion leaching from NiTi5Cr and subsequently low cytotoxicity. Thrombogenicity tests revealed significantly less platelet adhesion and confluent endothelial cell growth on polymer coated and uncoated ternary MEP Nitinol alloys. Finally, this research addresses the bio and hemocompatibility of MEP + PC ternary Nitinol alloys that could be used to manufacture blood contacting devices such as stents and vascular implants which can lead to lower U.S. healthcare spending.

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Books on the topic "Nitinol"

1

Davenport, Kathryn. Drug delivery coatings for nitinol stents to prevent intimal hyperplasia. Birmingham: University of Birmingham, 2002.

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Burlaka, Viktoriya. Premo-nition: Ukrainian art now. Edited by Saatchi Gallery. London: Booth-Clibborn Editions, 2014.

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MUKESH, Nitin. Duets of Nitin Mukesh. New Delhi: Super Cassettes Industries, 1989.

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Sierra Club of British Columbia. and Sierra Club of Western Canada., eds. The West Coast Trail and other great hikes: The Juan de Fuca Trail, the Carmanah-Walbran Trails, Nitinat Lakes. 8th ed. Vancouver: Greystone Books, 1998.

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Desai, Nitin. Dr. Nitin Desai on "demographic dividend or debt?": March 26, 2010, PHD House, New Delhi. New Delhi: Population Foundation of India, 2010.

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Cambodia. Gaṇàkammādhikār Jāti Riapcaṃ Kārpoḥchnot., ed. Sannipāt pūk srup kārnār poaḥchnot jroesroes kruṃ prẏksā ghuṃ saṅkât nitikāl dī 2 chnaṃ 2007, (Kruṅ Braḥ Sīhanu thnai dī 20-21 khae Usabhā chnaṃ 2007). [Phnom Penh]: Gaṇàkammādhikār Jāti Riapcaṃ Kārpoḥchnot, 2007.

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Leonardi, Laura, ed. Opening the european box. Florence: Firenze University Press, 2008. http://dx.doi.org/10.36253/978-88-8453-593-1.

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Viewed from a theoretical and empirical perspective, the ongoing process of Europeanization poses new challenges to sociology. As a science, sociology reveals the inadequacy of the conceptual and methodological instruments currently available for our understanding of European social phenomena. Sociologists fi nd it di cult to defi ne the very object under scrutiny: does a European society exist? How should we defi ne a society whose boundary lines are variable? Does a study of Europe from a sociological perspective entail a study of the European Union, or of a broader social formation? e di culty encountered in "studying Europe" in the sociological area is linked to a broader theoretical debate which, in the light of the ongoing processes of change, queries the entire cognitive apparatus and the theoretical paradigms developed by sociological disciplines and related to the modernity of the western world. e "national constellation" of norms, institutions and regulative techniques which have allowed political and social integration within the national state, are now challenged by phenomena which undermine their very epistemological foundations. e concepts applied to the study of social and political integration, - society, state, legitimacy, social inequality, mobility, justice, solidarity, etc.- are, in a classic defi nition of the term, no longer e cient in discerning the phenomena which impact on contemporary societies. e variety of themes discussed by several Italian and foreign authors explore many aspects of the workings of Europe; they reveal new theoretical and methodological perspectives with which we set out to study the political, social, cultural and economic phenomena which today characterize Europe.

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Majhamandal saṃrap Qbhivadhṅ Sangaṃ (Phnom Penh, Cambodia). Rapāykārn̊ stībī ṭamnoer kārprajuṃ Raṭṭhasabhā: Samăy prajuṃ sāmaññ loek dĩ 1 dī 2 niṅ dī 3 niṅ samăy prajuṃ wisāmaññ loek dī 1 nitikāl dī 3 câp bī thnai dī 15 Khae Dhnū Chnaṃ 2003 t̥al thnai dī 15 Khae Dhnū Chnaṃ 2005. Bhnaṃ Beñ: Majjhamaṇḍāl Qbhivaḍḍhn ̊Saṇgam, 2005.

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National Aeronautics and Space Administration (NASA) Staff. Charpy Impact Energy and Microindentation Hardness Of 60-Nitinol. Independently Published, 2019.

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Wagenknecht, Fred. Erfolgreich experimentieren mit Nitinol- Mini- Robotern. Memorymetall Muskeln im praktischen Einsatz. Franzis Verlag, 2000.

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Book chapters on the topic "Nitinol"

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Baker, Ian. "Nitinol." In Fifty Materials That Make the World, 137–42. Cham: Springer International Publishing, 2018. http://dx.doi.org/10.1007/978-3-319-78766-4_26.

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Strauß, S., A. Hahn, S. Barcikowski, K. Reimers, and P. M. Vogt. "Implantat Optimierung mittels Nitinol-Nanobeschichtungen." In Chirurgisches Forum und DGAV Forum 2010, 259–60. Berlin, Heidelberg: Springer Berlin Heidelberg, 2010. http://dx.doi.org/10.1007/978-3-642-12192-0_99.

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Kumar, Mukesh. "Nitinol-Based Shape-Memory Alloys." In Shape Memory Composites Based on Polymers and Metals for 4D Printing, 45–66. Cham: Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-030-94114-7_3.

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Rondelli, G., M. Francesca Brunella, Luigi De Nardo, and Alberto Cigada. "Corrosion Behaviour of Nitinol Vascular Stents." In Advances in Science and Technology, 252–57. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/3-908158-05-2.252.

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Perry, Kenneth E., and Alex Teiche. "Fatigue Crack Initiation in Superelastic Nitinol." In Fatigue and Fracture Metallic Medical Materials and Devices, 35–52. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 2013. http://dx.doi.org/10.1520/stp155920130030.

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Cortijo, René E., Millard Escalona, and Victor Laverde. "Hand Prosthesis with Nitinol: Shape Memory Alloy." In Advances in Intelligent Systems and Computing, 259–70. Cham: Springer International Publishing, 2019. http://dx.doi.org/10.1007/978-3-030-32033-1_24.

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Sroka, Ronald, Joachim Müller, and Florian Schrötzlmair. "Laser-Assisted Implantation of Nitinol Stapes Prosthesis." In Biomedical Optics in Otorhinolaryngology, 115–24. New York, NY: Springer New York, 2016. http://dx.doi.org/10.1007/978-1-4939-1758-7_8.

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Baz, A., S. Poh, J. Ro, M. Mutua, and J. Gilheany. "Active Control of Nitinol-Reinforced Composite Beam." In Solid Mechanics and Its Applications, 169–212. Dordrecht: Springer Netherlands, 1992. http://dx.doi.org/10.1007/978-94-017-1903-2_4.

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Azaouzi, Mohamed, Nadhir Lebaal, Ahmed Makradi, and Salim Belouettar. "Optimization Based Simulation of Self-expanding Nitinol Stent." In Lecture Notes in Mechanical Engineering, 423–30. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. http://dx.doi.org/10.1007/978-3-642-37143-1_50.

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Perry, Kenneth, Alex Teiche, and Izak McGieson. "Local Strain Analysis of Nitinol During Cyclic Loading." In Fracture, Fatigue, Failure and Damage Evolution, Volume 8, 157–64. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-21611-9_20.

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Conference papers on the topic "Nitinol"

1

Zende, Stefan, Moritz Pohler, Lucas Bittigkoffer, and Nils-Agne Feth. "Hot Forming of Nitinol: Fundamental Investigations and Applications." In SMST2022. ASM International, 2022. http://dx.doi.org/10.31399/asm.cp.smst2022p0095.

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Abstract Nitinol's thermomechanical properties are well studied and understood below the so-called martensite death (MD) temperature, above which martensite cannot be induced by mechanical stress: Even at high stresses Nitinol stays in the austenite phase. This paper presents tensile tests performed well above MD (>150 °C) with Nitinol specimens laser cut from tube. The investigations show that Nitinol drastically changes its mechanical properties in this temperature range: The superelastic plateau shortens and finally vanishes. Furthermore, Nitinol starts becoming more ductile.

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Skalitzky, Amanda, Caleb Petersen, Austin Gurley, and David Beale. "Woven Nitinol Fabric Strips Characterized in Tension via Finite Element Analysis and Geometric Modeling." In ASME 2019 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2019. http://dx.doi.org/10.1115/smasis2019-5669.

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Abstract Nitinol in the form of wires, tubes, and plates have been explored extensively; however, the characteristics of Nitinol as a woven fabric have so far been little-studied analytically. It would be easier to design such a fabric if conventional fabric models were known to apply to Nitinol fabrics, potentially with modifications required by Nitinol’s unique properties. A 25 mm wide Nitinol narrow fabric has been manufactured using traditional weaving equipment using a proprietary process that achieves a uniform and tight weave. Heat-treatment and straight shape-set is applied to a single Nitinol wire and the woven Nitinol fabric at 600°C for 30 minutes. The 0.25 mm Nitinol wire constituent was tested using differential scanning calorimetry (DSC) to determine the transition temperatures (Mf, Ms, As, and Af), which were found on average to be 54.5°C, 66.9°C, 88.7°C, and 103.5°C respectively. Both the Nitinol wire and fabric were tested in a temperature-controlled chamber (testing temperatures ranged from room temperature to 200°C) in which the tensile stress-strain characteristics were observed. It was determined that existing analytical models can be employed to accurately estimate the overall tensile stiffness of woven Nitinol fabrics in a small-strain regime. Additionally, it was confirmed that the tensile loading of woven Nitinol fabric can be modeled in MSC.Adams with beam elements. In combination with the geometric model presented, woven Nitinol fabric behavior can be predicted from the experimental behavior of the constituent Nitinol wire.

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Walker, Jason, Mohammad Elahinia, and Christoph Haberland. "An Investigation of Process Parameters on Selective Laser Melting of Nitinol." In ASME 2013 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/smasis2013-3074.

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Nitinol’s superelastic and shape memory effects can be used in passive or active actuation systems. Often used in the aerospace industry, the use of Nitinol for actuation is also growing in the biomedical fields and elsewhere. However, the industry currently lacks the ability to produce complex Nitinol actuators, which is strictly limiting its potential. The extreme difficulty of machining Nitinol complicates manufacturing processes. Furthermore, the transformation temperatures which drive Nitinol’s unique behavior are extremely sensitive to the relative concentrations of nickel and titanium. Therefore, exceptionally tight compositional control during production is necessary to guarantee ideal material behavior. Additive manufacturing (AM) is a near-net-shaping technology which allows for the direct fabrication of complex metallic components. In this way, the (lack of) machinability of Nitinol is no longer an issue because no traditional machining is required during fabrication. Using AM also enables production of 3D geometries that are not possible using traditional techniques. Features such as engineered porosity, hollow parts, curved holes and filigree structures are suddenly realizable. Furthermore, direct CAD fabrication reduces the timescale of the concept-to-prototype transition. A major breakthrough in additive manufacturing came with the development of fiber laser technology in the mid-1990’s, which enables direct melting of manufacturing grade metals into fully dense parts. This technology became known as selective laser melting (SLM). Despite its huge potential, SLM of Nitinol has received little attention from the engineering world. In the present work, two different SLM machines (Realzier SLM 100 and Phenix Systems PXM) are used to develop Nitinol components directly from powder. Adjustment and optimization of the process parameters on the product are analyzed and compared.

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Wang, Frederick E. "The Thermobile Nitinol Engine." In 1985 SAE International Off-Highway and Powerplant Congress and Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1985. http://dx.doi.org/10.4271/851495.

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Fonte, Matthew, and Anil Saigal. "Crystallographic Texture of Nitinol and its Effects on Macrophage." In ASME 2010 International Mechanical Engineering Congress and Exposition. ASMEDC, 2010. http://dx.doi.org/10.1115/imece2010-37109.

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The use of Nitinol for medical purposes was first reported in the late 1960’s. Today Nitinol is commonly used for the manufacture of stents, which are primarily used in peripheral and coronary bypass graft interventions. The application of NiTi in orthopedics is an exciting prospect but one that has yet to be realized. Nitinol’s unique mechanical behavior is derived from the coordinated atomic movements manifesting in phase transformations from cubic austenite to monoclinic martensite. These phase transformations are solid-to-solid phase transformations that occur without diffusion or plasticity, potentially making them reversible. They involve changes in the crystalline structure that can be induced by changes in either temperature or stress. In addition to phase transformations, Nitinol’s mechanical strength is strongly dependent on the alloy composition and the method in which the material is processed, i.e. rolled, drawn, extruded, or forged. The mechanical work, combined with the intermediate heat treatment steps, contribute to modify microstructure, transformation temperatures and mechanical properties. These manufacturing processing steps lead to texturing (crystallographic alignment) of the material. Alignment of the atomic planes from texture in the polycrystalline material have a marked influence on the mechanical response by either limiting or promoting phase transformations and shape recovery strains. Nitinol is an established biomaterial, whose biocompatibility is heavily grounded on the inertness of titanium based oxides that usually dominate the surface exterior. Surfaces that vary significantly in their chemistry, topography and corrosion resistance have different degrees of biocompatibility. As such, a better understanding of the biological response of NiTi’s surfaces with different crystallographic textures in needed. In the present research, a macrophage study is performed whereby 6 plates that are highly textured NiTi with different surface finishes are incubated with cells for approximately 3 days and then tumor necrosis factor (TNF), a pro-inflammatory cytokine production and cellular proliferation are assessed.

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6

Witt, Alana Rocha Schmidt, Luciane Thaís Führ, Leonardo Marasca Antonini, Simone Vendruscolo Milesi, Denis Villarinho, and Célia de Fraga Malfatti. "CARACTERIZAÇÃO ELETROQUÍMICA DE NITINOL ANODIZADO." In 13º ENEMET - Encontro Nacional de Estudantes de Engenharia Metalúrgica, de Materiais e de Minas. São Paulo: Editora Blucher, 2013. http://dx.doi.org/10.5151/2594-4711-23079.

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Ibrahim, Ghaleb, Salem Haggag, Laith Al Qassem, Moon Diab, and Hadi Abbas. "Thermal Engine Using Nitinol Wire." In 2019 IEEE Global Engineering Education Conference (EDUCON). IEEE, 2019. http://dx.doi.org/10.1109/educon.2019.8725041.

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Walker, Jason, Mohsen Taheri Andani, Christoph Haberland, and Mohammad Elahinia. "Additive Manufacturing of Nitinol Shape Memory Alloys to Overcome Challenges in Conventional Nitinol Fabrication." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-40432.

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The pseudoelastic and shape memory effects of NiTi can be used in passive or active actuation systems. Often used in the aerospace industry, the use of NiTi for actuation is also growing in the biomedical fields and elsewhere. However, it’s potential in industry is currently limited by the inability to produce complex NiTi parts. Conventional manufacturing processes are complicated by the extreme difficulty associated with machining NiTi. Furthermore, the transformation temperatures which drive the unique behavior of NiTi as a shape memory alloy are extremely sensitive to the relative concentrations of nickel and titanium. Therefore, exceptionally tight compositional control during production is necessary to guarantee ideal material behavior. Additive manufacturing (AM) is a near-net-shaping technology which allows for the direct fabrication of complex metallic components. By utilizing the AM processing principle, the poor machinability of NiTi is no longer an issue. Using AM also enables production of 3D geometries that are not possible using traditional techniques. Furthermore, direct CAD fabrication reduces the timescale of the concept-to-prototype transition. In the present work, an SLM machine (Phenix Systems PXM) is used to develop NiTi components directly from powder. The thermal characteristics and shape memory functionality of SLM NiTi components is demonstrated.

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Gong, Xiao-Yan, Craig L. Bonsignore, and Alan R. Pelton. "A “Point Cloud” Approach in Superelastic Stent Design." In ASME 2001 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2001. http://dx.doi.org/10.1115/imece2001/bed-23083.

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Abstract Figure 1 shows schematically the stress-strain relation for Nitinol under uniaxial tensile test at constant temperature. Originally, material is in the Austenite phase. Upon loading, below a small strain, ε1, stress is linearly proportional to the strain. The slope defines the Young’s modulus of Nitinol in Austenite phase. When strain reaches beyond ε1, a small increase in stress induces a large amount of strain owing to the phase transition from Austenite to Martensite. After completion of the phase transition, for strain larger than ε2, the stress and strain relation is linear again with a different slope, which defines the modulus of Martensite phase. During unloading, Martensite remains until strain ε3, which is less than ε2. Below ε3, the Martensite reverts to Austenite and a large reverse strain is produced until ε4, which is smaller than ε1. After unloading below ε4, the material returns to linear elastic behavior. This unique material behavior of Nitinol, known as superelasticity, along with its excellent biocompatibility and corrosion resistance, makes Nitinol a perfect material candidate for self-expanding stent applications. Self-expanding stents made of Nitinol offer unique features such as biased stiffness to better fit the anatomy and excellent corrosion resistance. When implanted in vivo, stents are subjected to the pulsatile loading from systolic and diastolic heartbeats and therefore it is necessary to design for a long (10 years) fatigue life. Nitinol’s fatigue behavior is known to depend upon the mean and the alternating strains from cyclic loading. Therefore, one approach to ensure that the stent has a long fatigue life is to design in such a manner that both the mean and the alternating strains of the proposed stent are lower than the Nitinol’s fatigue endurance limits. For linear materials, this normally is not an issue as the location of the maximum mean strain is also the location of maximum alternating strain, therefore the history of the maximum strain point can be used to predict the device fatigue life or used as the design criterion. However, Nitinol is a highly nonlinear and path dependent material that makes it possible that the location of the maximum mean strain is not necessarily the location of maximum alternating strain. A rigorous design criterion is developed at Nitinol Devices and Components (NDC) to trace the strain history of every material point. We accomplish this by means of a nonlinear finite element analysis (FEA) using ABAQUS. The FEA analysis uses a special user-defined material subroutine by HKS/WEST customized for Nitinol. The loading condition on the stents can come from two sources: 1. An analytical approach to determine the stent diameters by balancing the stent within a 6% compliant tube to simulate physiological loading, or 2. A direct measurement of stent diameter change inside the tube from the in-vitro testing. This article demonstrates the criterion using the second approach, i.e., the measured stent diameters are used as the FEA input. The mean and alternating strains at every element integration point or when extrapolated at every node produces a single point in the mean and alternating strain plane. The discretized stent produces “point clouds”. When this “point cloud” plot is superimposed on the fatigue endurance limit, the designer will have an idea of the relative safety of the design. The results are compared with the linear approach using traditional beam theory. It is verified that when the deformation is small, the beam theory agrees well with the nonlinear FEA analysis.

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Anderson, Walter, Christoph Haberland, and Mohammad Elahinia. "A Minimally Invasive Cage for Spinal Fusion Surgery Utilizing Superelastic Hinges." In ASME 2013 Conference on Smart Materials, Adaptive Structures and Intelligent Systems. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/smasis2013-3144.

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A prototype cage implant for spinal fusion surgery has been designed and developed. Spinal fusion surgery is sometimes performed to alleviate low back pain. The cage implant is a spacer that sits in between two vertebrae to allow for bone growth and fusion, all while relieving compression of the spinal cord. The cage implant is minimally invasive in nature, utilizing embedded nitinol hinges as dual purpose actuators and assembly structural elements. The cage implant utilizes elliptical shaped nitinol hinge pins as actuators to allow the cage to be in a straightened before deployment and manipulate its shape to an oblong octagon once within the disc space. A new modeling technique was developed to aid with the design of the nitinol ellipses. The model is MATLAB based and accounts for the non Mises behavior of nitinol through a correction factor for mapping the effective stress and strain. A nitinol rod and an elliptical geometry were examined experimentally and show the robustness of the developed model. These experiments were conducted to design the nitinol hinges for the cage implant. The cage implant is made of two different materials, nitinol hinge actuators and the containing titanium structural segments. The nitinol hinge actuators are completely enclosed within the medical grade titanium segments through the use of selective laser sintering.

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Reports on the topic "Nitinol"

1

Strasberg, Matthew. Determining Micromechanical Strain in Nitinol. Office of Scientific and Technical Information (OSTI), September 2006. http://dx.doi.org/10.2172/892605.

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Goldstine, David, and Ens A. Weiner. NITINOL-Based Fuze Arming Component. Fort Belvoir, VA: Defense Technical Information Center, October 1988. http://dx.doi.org/10.21236/ada207409.

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Goldstein, David M., Lawrence T. Kabacoff, and John Tydings. Effects of Stresses on the Phase Transformation of NITINOL. Fort Belvoir, VA: Defense Technical Information Center, April 1986. http://dx.doi.org/10.21236/ada177053.

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Robertson, Scott W. On the Mechanical Properties and Microstructure of Nitinol forBiomedical Stent Applications. Office of Scientific and Technical Information (OSTI), January 2006. http://dx.doi.org/10.2172/901533.

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Bibee, Mathew. Mapping Strain in Nanocrystalline Nitinol: an X-ray Diffraction Method (SULI paper). Office of Scientific and Technical Information (OSTI), January 2006. http://dx.doi.org/10.2172/877996.

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Baz, Amr M., Karim R. Iman, and John J. McCoy. Active Control of Flexible Space Structures Using the Nitinol Shape Memory Actuators. Fort Belvoir, VA: Defense Technical Information Center, October 1987. http://dx.doi.org/10.21236/ada205948.

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Owens, Erich. Development of Powder Diffraction Analysis Tools for aNanocrystalline Specimen: An Emphasis upon NiTi (Nitinol). Office of Scientific and Technical Information (OSTI), August 2006. http://dx.doi.org/10.2172/891239.

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Benac, D. J., and H. C. Burghard. Sealed source and device design safety testing: Technical report on the findings of task 4 -- Investigation of failed Nitinol brachytherapy wire. Volume 2. Office of Scientific and Technical Information (OSTI), March 1996. http://dx.doi.org/10.2172/226076.

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Badia, R., J. Ejarque, S. Böhm, C. Soriano, and R. Rossi. D4.4 API and runtime (complete with documentation and basic unit testing) for IO employing fast local storage. Scipedia, 2021. http://dx.doi.org/10.23967/exaqute.2021.9.001.

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This deliverable presents the activities performed on the ExaQUte project task 4.5 Development of interface to fast local storage. The activities have been focused in two aspects: reduction of the storage space used by applications and design and implementation of an interface that optimizes the use of fast local storage by MPI simulations involved in the project applications. In the rst case, for one of the environments involved in the project (PyCOMPSs) the default behavior is to keep all intermediate les until the end of the execution, in case these les are reused later by any additional task. In the case of the other environment (HyperLoom), all les are deleted by default. To unify these two behaviours, the calls \delete object" and \detele le"have been added to the API and a ag \keep" that can be set to true to keep the les and objects that maybe needed later on. We are reporting results on the optimization of the storage needed by a small case of the project application that reduces the storage needed from 25GB to 350MB. The second focus has been on the de nition of an interface that enables the optimization of the use of local storage disk. This optimization focuses on MPI simulations that may be executed across multiple nodes. The added annotation enables to de ne access patters of the processes in the MPI simulations, with the objective of giving hints to the runtime of where to allocate the di erent MPI processes and reduce the data transfers, as well as the storage usage.

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