Journal articles: 'Ceramic cores'

1

Chiang, Ting-Yi, Chun-Chuan Yang, Yi-Hsuan Chen, Min Yan, and Shinn-Jyh Ding. "Shear Bond Strength of Ceramic Veneers to Zirconia–Calcium Silicate Cores." Coatings 11, no. 11 (October 29, 2021): 1326. http://dx.doi.org/10.3390/coatings11111326.

Full text

Abstract:

Improving the bond strength of veneering ceramics to ZrO2-based cores remains a challenge. The purpose of this study was to evaluate the shear bond strength of different ZrO2 cores containing calcium silicate (CaSi) to veneering ceramics. Five types of ZrO2-based cores (n = 230) were divided into two groups: with or without oxygen plasma treatment. These were bound to two veneering ceramics (IPS e.max Ceram or VITA VM9). Shear bond strength of veneering ceramics to various cores was measured (n = 10), in addition to phase composition, surface morphology and contact angle of the cores. The results indicated that the plasma treatment had a significant effect on the water contact angle of the ZrO2-based cores, but had little effect on the bond strength. Regardless of plasma treatment, the highest strength value was recorded in the ZrO2 core specimen containing 20 wt % CaSi, when all cores were adhered to VITA VM 9 veneer. When using IPS e.max Ceram veneer, the shear bond strength of the plasma-treated 20 wt % CaSi-containing ZrO2 core was 16.6 ± 0.9 MPa higher than that of VITA In-Ceram YZ core control (13.4 ± 1.0 MPa) (p < 0.05). We conclude that the presence of 20 wt % CaSi in ZrO2 can improve the shear bond strength of zirconia-based cores to veneering ceramic.

APA, Harvard, Vancouver, ISO, and other styles

2

Yu, Jian Bo, Zhi Gang Yang, Chuan Jun Li, Kang Deng, and Zhong Ming Ren. "Investigation on Properties of the Silica Ceramic Cores for the Hollow Blades Prepared by the Conversion of the Silicon Resin." Key Engineering Materials 680 (February 2016): 267–71. http://dx.doi.org/10.4028/www.scientific.net/kem.680.267.

Full text

Abstract:

The working conditions of the ceramic cores are extremely harsh with the development of the preparation technology and improvement of the use conditions in the hollow blades, which brings forward high request for the preparation and properties of the ceramic cores. In this paper, silica ceramic powders were firstly coated by the silicon resin. The obtained composite powders were used to prepare the ceramic cores by the dry pressing method. And the phase compositions, microstructure and properties of the ceramic cores with the sintering temperatures were investigated. The results showed that the composite powders prepared by the coating showed good formability. The sintering temperature promoted the formation of the cristobalite. With the increase of the sintering temperature, the porosity of ceramic cores gradually decreased, the shrinkage rate and bulk-density increased. The prepared ceramic cores at 1250°C had highest bend strength of 19.25Mpa.

APA, Harvard, Vancouver, ISO, and other styles

3

Li, Xin, Shuxin Niu, Dongsheng Wang, Jie Li, Qi Jiao, Xinlong Guo, and Xiqing Xu. "Microstructure and Crystallization Kinetics of Silica-Based Ceramic Cores with Enhanced High-Temperature Property." Materials 16, no. 2 (January 8, 2023): 606. http://dx.doi.org/10.3390/ma16020606.

Full text

Abstract:

Silica-based ceramic cores play key roles in the casting of aeroengine blades, but they are highly limited by the poor high-temperature mechanical property. Here, fused mullite (FM) and sintered mullite (SM) powders were modified in silica-based ceramic cores, and the microstructure evolution and crystallization kinetics of ceramic cores depending on mullite types were studied. The ceramic cores with FM showed a dense microstructure and superior mechanical properties compared to those with SM. The ceramic cores with 10 wt.% of FM showed a crystallization activation energy of 1119.5 kJ/mol and a crystallization exponent of 1.74, and the values of 938.4 kJ/mol and 1.86 as SM were employed; the decreased crystallization activation energy and the elevated crystallization exponent by SM suggested that the excess impurities of alkali oxides and alkaline-earth oxides significantly promoted the crystallization of cristobalite. Even though the ceramic cores with mullite powders decreased slightly in the room-temperature mechanical property, their high-temperature flexure strength and creep deformation resistance were enhanced. The ceramic cores with 10 wt.% of FM showed excellent comprehensive performance, with linear shrinkage of 0.69%, room-temperature strength of 18.9 MPa, and high-temperature strength of 15.5 MPa, which satisfied the demands for hollow-blade casting.

APA, Harvard, Vancouver, ISO, and other styles

4

Liu, Xiao-fu, Xin-li Guo, Guo-yan Shui, Chang-chun Li, Gui-qiao Su, Xun Sun, Yang Guan, and Lei Jin. "Properties of alumina-based ceramic cores." China Foundry 18, no. 6 (November 2021): 593–98. http://dx.doi.org/10.1007/s41230-021-1125-4.

Full text

APA, Harvard, Vancouver, ISO, and other styles

5

Zheng, Wen, Jia-Min Wu, Shuang Chen, Chang-Shun Wang, Chun-Lei Liu, Shuai-Bin Hua, Kang-Bo Yu, Jie Zhang, Jing-Xian Zhang, and Yu-Sheng Shi. "Influence of Al2O3 content on mechanical properties of silica-based ceramic cores prepared by stereolithography." Journal of Advanced Ceramics 10, no. 6 (September 28, 2021): 1381–88. http://dx.doi.org/10.1007/s40145-021-0513-y.

Full text

Abstract:

AbstractSilica ceramic cores have played an important part in the manufacture of hollow blades due to their excellent chemical stability and moderate high-temperature mechanical properties. In this study, silica-based ceramics were prepared with Al2O3 addition by stereolithography, and the influence of Al2O3 content on mechanical properties of the silica-based ceramics was investigated. The Al2O3 in silica-based ceramics can improve the mechanical properties by playing a role as a seed for the crystallization of fused silica into cristobalite. As a result, with the increase of Al2O3 content, the linear shrinkage of the silica-based ceramics first decreased and then increased, while the room-temperature flexural strength and the high-temperature flexural strength first increased and then decreased. As the Al2O3 content increased to 1.0 vol%, the linear shrinkage was reduced to 1.64% because of the blocked viscous flow caused by Al2O3. Meanwhile, the room-temperature flexural strength and the high-temperature flexural strength were improved to 20.38 and 21.43 MPa with 1.0 vol% Al2O3, respectively, due to the increased α-cristobalite and β-cristobalite content. Therefore, using the optimal content of Al2O3 in silica-based ceramics can provide excellent mechanical properties, which are suitable for the application of ceramic cores in the manufacturing of hollow blades.

APA, Harvard, Vancouver, ISO, and other styles

6

Ozcan, Nihal, and Erdal Sahin. "In vitro evaluation of the fracture strength of all-ceramic core materials on zirconium posts." European Journal of Dentistry 07, no. 04 (October 2013): 455–60. http://dx.doi.org/10.4103/1305-7456.120671.

Full text

Abstract:

ABSTRACT Objective: For most endodontically treated teeth, tooth-colored post-core systems are preferable for esthetic reasons. Therefore, improvements in material strength must also consider tooth colored post-core complexes. The objective of this study was to evaluate the difference in tooth colored post-core complex strengths. Materials and Methods: A total of 33 human maxillary central incisor teeth were used for this study, with three groups of 11 teeth. Three different methods were used to fabricate all-ceramic post-core restorations: zirconia blanks, Cerec 3D-milled to one-piece post-core restorations (Test Group 1); feldspathic cores (from feldspathic prefabricated CAD/CAM blocks) adhesively luted to CosmoPost zirconia posts (Test Group 2); and IPS Empress cores directly pressed to CosmoPost zirconia posts (Test Group 3). All-ceramic crowns from feldspathic ceramic were constructed using a CAD/CAM system (Cerec 3D) for all specimens. The post-core complexes were tested to failure with the load applied at 45° angled relative to the tooth long axis. The load at fracture was recorded. Results: The maximum fracture strength of the milled zirconia cores (Test Group 1) was 577 N; corresponding values for the milled feldspathic cores (Test Group 2) and the pressed cores (Test Group 3) were 586 and 585 N, respectively. Differences were not statistically significant at P < 0.05 (P = 0.669). Conclusions: All-ceramic cores adhesively luted on zirconia posts and one-piece all-ceramic zirconium post-core structures offer a viable alternative to conventional pressing.

APA, Harvard, Vancouver, ISO, and other styles

7

Zhou, Pengpeng, Guoqing Wu, Faheem K. Butt, Ye Tao, Jiaqi Zhao, and Hai Nan. "Preparation of Y2O3 Coated CaO Ceramic Cores with Anti-Hydration Performance and High-Interface Stability Against Interface Reaction of Ti–6Al–4V Alloys." Journal of Nanoscience and Nanotechnology 19, no. 6 (June 1, 2019): 3420–28. http://dx.doi.org/10.1166/jnn.2019.16034.

Full text

Abstract:

In this study, we describe a novel method for preparing Y2O3@CaO ceramic cores with anti-hydration performance and high-interface stability against interface reaction of Ti–6Al–4V alloys. The effect of Y2O3 coating on microstructure, mechanical, anti-hydration properties of ceramic cores and interface reaction with Ti–6Al–4V alloys was studied. The results show that the surface charge of Y2O3 and CaO are opposite at the pH value of 13, which might result in an electrostatic force and become the main driving force of Y2O3 particles absorb on the surface of CaO particles. The Y2O3 coating improved the anti-hydration properties of the CaO-based ceramic cores after sintering at 1450 °C. Meanwhile, the flexural strength improved from 11.2 to 18.8 MPa. At last, the interaction between the ceramic cores and Ti–6Al–4V metal were studied by centrifugal investment casting. Y2O3 coating can effectively reduce the interface reaction and the thickness of the interaction layer in the casting was less than 10 μm. The results suggest that the Y2O3@CaO ceramic with anti-hydration performance provide excellent mechanical and high-interface stability against interface reaction of Ti–6Al–4V alloys.

APA, Harvard, Vancouver, ISO, and other styles

8

Rassokhina, L. I., O. N. Bityutskaya, M. V. Gamazina, and V. V. Avdeev. "FEATURES OF THE DEVELOPMENT OF TECHNOLOGIES FOR THE MANUFACTURE AND REMOVAL OF CERAMIC CORES BASED ON FUSED QUARTZ FOR CASTING TURBINE BLADES FROM SUPERALLOYS." Proceedings of VIAM, no. 2 (2022): 3–12. http://dx.doi.org/10.18577/2307-6046-2022-0-2-3-12.

Full text

Abstract:

Technological parameters of removal of ceramic cores based on fused quartz from the inner cavity of turbine blade castings are selected and investigated. The results of studies of technological parameters of removal of ceramic cores based on fused quartz are presented, according to the results of which optimal technological parameters are selected and a technology for removing ceramic rods from fused quartz from the inner cavity of turbine blade castings is developed.

APA, Harvard, Vancouver, ISO, and other styles

9

Qin, Ye Xia, Ai Bing Du, Rui Zhang, and Wei Pan. "Properties of In Situ Synthesized Alumina Ceramic Core Composites." Key Engineering Materials 368-372 (February 2008): 724–25. http://dx.doi.org/10.4028/www.scientific.net/kem.368-372.724.

Full text

Abstract:

A series of alumina-based ceramic cores were in situ prepared. Effect of kyanite on the properties of ceramic core was discussed. The results indicated that the microstructure of the core is characterized by the presence of unreacted Al2O3 particles having a polycrystalline composition consisting essentially of in-situ synthesized 3Al2O3 .2SiO2 on the surface of the Al2O3 particles. The ceramic cores of kyanite contents sintered at 1500oC for 3 h have almost no creep deformation.

APA, Harvard, Vancouver, ISO, and other styles

10

Vavřičková, Lenka, T. Dostálová, J. Charvát, and M. Bartoňová. "Evaluation of the Three-year Experience with All-ceramic Crowns with Polycrystalline Ceramic Cores." Prague Medical Report 114, no. 1 (2013): 22–34. http://dx.doi.org/10.14712/23362936.2014.35.

Full text

Abstract:

The objective of the study was to evaluate the clinical outcomes of all-ceramic crowns three years after placement of the restoration in the oral cavity. The aim of the present clinical study were surveyed the Procera®, Cercon® and LAVA™ systems. In total, 121 crowns were followed in 33 patients (7 men and 26 women) with an average age of 53.5 years. The eighty crowns were placed in anterior and forty one crowns in posterior teeth. The crowns were fabricated in two dental laboratories and delivered in two private dental practices. The clinical trial was conducted according to American Dental Association guidelines. The patients were requested to provide their consent to the regular clinical examination including radiographic and photographic records. A total of 102 crowns were made of zirconium oxide ceramic cores – 58 Cercon®; 43 LAVA™, while 19 crowns were made of aluminum oxide cores Procera®. The veneering ceramic LAVA™ Ceram was used. The success rate was analyzed using Kaplan-Meier statistics and, in our case, the overall three-year success rate reached 96.7%. All-ceramic crowns with polycrystalline ceramic cores have low susceptibility to fracture, in this study just 3.3%.

APA, Harvard, Vancouver, ISO, and other styles

11

Zhu, Wei-Jun, Guo-Qiang Tian, Yang Lu, Kai Miao, and Di-Chen Li. "Leaching improvement of ceramic cores for hollow turbine blades based on additive manufacturing." Advances in Manufacturing 7, no. 4 (September 26, 2019): 353–63. http://dx.doi.org/10.1007/s40436-019-00273-2.

Full text

Abstract:

Abstract The precision casting method based on alumina-based ceramic cores is one of the main techniques used to manufacture hollow turbine blades. Additive manufacturing (AM) technology provides an alternate solution to fabricating ceramic cores quickly and precisely. As the complexity of the structure increases and the strength of the material improves, the leaching process of the cores becomes more complicated. This study proposes a compound pore-forming method to increase the porosity of ceramic cores by adding a preformed-pore agent and materials that convert to easy-to-corrode phases. The preformed-pore agents (e.g., carbon fibers) can be burned off during sintering to form pores before the leaching, and the easy-to-corrode phases (e.g., CaCO3, SiO2, β-Al2O3) can be leached firstly to form pores during the leaching process. The pores formed in the aforementioned two stages increase the contact area of the cores and leaching solution, thus improving the leaching rate. In the current study, the additive amount of the preformed-pore agent was optimized, and the effect of the easy-to-corrode phases on the comprehensive properties of the cores was then compared. Based on this, the corresponding model was established.

APA, Harvard, Vancouver, ISO, and other styles

12

Huerta, A., R. Ordoñez, H. A. Calderon, M. Umemoto, K. Tsuchiya, H. Balmori, E. Reguera, and H. Yee-Madeira. "Characterization and Production of Structurat Ceramics in the Systems Fe(1-X)O-Fe3O4 and MgO-MgFe2O4." Microscopy and Microanalysis 5, S2 (August 1999): 810–11. http://dx.doi.org/10.1017/s1431927600017372.

Full text

Abstract:

Ceramic materials are widely studied for their high temperature structural applications. In many crystalline ceramics the range of solid solution decreases with temperature and thus precipitation of a second phase occurs. Thus, ceramics can be hardened by precipitation of second phases. However little is known regarding the effect of precipitation and nanocrystalline grain structure in the ductility of ceramic materials. On the other hand, oxide ceramics are under intense-investigation for their technological advantages in magnetization, dielectric response and chemical stability in such diverse uses as magnetic recording media, induction cores and microwave resonant circuits. This investigation has been undertaken to produce, characterize and measure the properties of ceramics that can be hardened by precipitation. The selected systems include Fe(1-x)O-Fe3 and MgO MgFe2O4. Mechanical milling is used to produce nanocrystalline ceramic oxides in the systems Fe(1-x)O-Fe3 and MgO-MgFe2O4 The mechanically alloyed powders are consolidated by means of spark plasma sintering (SPS) at temperatures ranging from 673 K to 1273 K and a pressure varying from 500 to 50 MPa in vacuum.

APA, Harvard, Vancouver, ISO, and other styles

13

Zlatkov, B. S., E. Griesmayer, H. Loibl, O. S. Aleksic, H. Danninger, C. Gierl, and L. S. Lukic. "Recent advances in CIM technology." Science of Sintering 40, no. 2 (2008): 185–95. http://dx.doi.org/10.2298/sos0802185z.

Full text

Abstract:

In this article the PIM (Powder Injection Moulding) technology is described in brief. After that the benefits and advantages were analyzed and summarized. Ceramic injection moulding (CIM) process was analyzed in more detail: CIM- alumina, CIM-zirconia and CIM ferrites as the most common technical ceramics in CIM ceramic parts production, medical applications and accessories in chemical laboratories, and cores in electronic inductive components. After that our results for CIM barium hexaferrite and piezo ceramics (barium titanate) are given. The main powder characteristics, the shrinkage and density and the main electrical characteristics of the sintered samples were compared for the isostatically pressed PM (powder metallurgy) and CIM formed samples. SEM fractographs of CIM and PM samples are given for CIM green parts, debinded (white) parts and sintered parts, and PM green parts and sintered parts. The results obtained were compared to literature data before they were applied in ceramic components production.

APA, Harvard, Vancouver, ISO, and other styles

14

Xu, Xiao Qing, Peng Gao, and Tie Tao Zhou. "Research of Calcium Oxide Based Ceramic Cores in Titanium Casting." Key Engineering Materials 531-532 (December 2012): 266–71. http://dx.doi.org/10.4028/www.scientific.net/kem.531-532.266.

Full text

Abstract:

Ceramic cores are playing a more and more important role in the modern precision casting industry system; it could influence the internal structure and performance of the castings. Especially in the precision casting field, the internal structure directly influenced the ultimate properties. This paper investigated the calcium oxide ceramic cores used in titanium precision casting fields through changing the ratio of aggregate sizes and sintering process. The main properties as bend strength, sintering shrinkage, casting reaction layer and microstructure are performed using SEM, XRD and other measurement method. Results of this research showed that the calcium oxide ceramic cores could be used in titanium precision casting, provide a stable casting property and nearly without reaction pollution to the titanium castings.

APA, Harvard, Vancouver, ISO, and other styles

15

Beaulardi, Leandro, Alida Brentari, Martino Labanti, Enrico Leoni, Claudio Mingazzini, Sergio Sangiorgi, and Matteo Villa. "Microstructural and Thermo-Mechanical Characterization of Yttria Ceramic Cores for Investment Casting, with and without Particulate Reinforcement." Advances in Science and Technology 65 (October 2010): 33–38. http://dx.doi.org/10.4028/www.scientific.net/ast.65.33.

Full text

Abstract:

Yttria is an interesting material for the production of high performance ceramic cores for Directionally Solidified investment casting. DS casting of superalloys of the last generation challenge conventional silica ceramic cores, because of the high temperatures and the long times involved. Compared to silica, yttria is characterized by improved mechanical properties and higher chemical resistance at high temperatures. Submicronic and nanometric SiC reinforcements were tested in order to increase compression creep resistance of yttria. Oxidation resistance of both reinforcements was tested in conditions simulating the industrial process. The experimental results demonstrated the increase of compression creep resistance and showed that the industrial application of yttria ceramic cores reinforced with submicronic SiC is possible with minimal changes to current practices, thanks to a high enough oxidation resistance.

APA, Harvard, Vancouver, ISO, and other styles

16

Rani, Sapna, Jyoti Devi, Chandan Jain, Parul Mutneja, and Mahesh Verma. "Esthetic Rehabilitation of Anterior Teeth with Copy-Milled Restorations: A Report of Two Cases." Case Reports in Dentistry 2017 (2017): 1–5. http://dx.doi.org/10.1155/2017/2841398.

Full text

Abstract:

Digitalization has become part and parcel of contemporary prosthodontics with the probability of most of the procedures being based on the digital techniques in the near future. This digital revolution started in the latter half of the 20th century by converting analog objects/signals into digital bits and bytes. Recent developments in all-ceramic materials and systems of computer-aided designing and computer-aided manufacturing (CAD/CAM), copy milling, and so forth offer excellent esthetics and superb biocompatibility. Copy milling system for ceramics enables milling of the zirconia cores of all-ceramic restorations precisely and also if this system is properly used the procedure for fabricating all-ceramic restorations can be substantially simplified. This case report presents fabrication of all-ceramic Maryland Bridge and post-core with a copy milling system for esthetics and preservation of integrity of tooth. For both of the patients, the use of biologic, all-ceramic, copy-milled restorations resulted in clinical success and recovered function and esthetics.

APA, Harvard, Vancouver, ISO, and other styles

17

Li, Xin, Jian Sheng Yao, Xiao Guang Liu, Hong Na Fan, and Shu Xin Niu. "Microstructure and Performance of Fused Silica-Based Ceramic Core Reinforced by Mullite Fiber." Materials Science Forum 848 (March 2016): 228–32. http://dx.doi.org/10.4028/www.scientific.net/msf.848.228.

Full text

Abstract:

Fused silica-based ceramics are often used as sacrificial cores in investment castings to produce hollow, precise, and complex-shaped blades. In this work, the content of mullite fiber and its effects on mechanical and dimension behavior of silica-based ceramic cores were investigated. In order to simulate the single crystal blades casting process, the sintered samples were also heated up to 1540°C and kept for 0.5 h. Flexural strength test at 1540°Cwas carried out for the samples. The shrinkage, creep behavior and erode behavior were characterized. The results showed that in the premise of maintaining strength of materials, mullite fiber could decrease significantly the shrinkage. Many gains appeared on the surface of fiber after creep test of the core samples at 1540°C.

APA, Harvard, Vancouver, ISO, and other styles

18

Gromada, Magdalena, Adam Świeca, Marek Kostecki, Andrzej Olszyna, and Rafał Cygan. "Ceramic cores for turbine blades via injection moulding." Journal of Materials Processing Technology 220 (June 2015): 107–12. http://dx.doi.org/10.1016/j.jmatprotec.2015.01.010.

Full text

APA, Harvard, Vancouver, ISO, and other styles

19

Zhang, Xiandong, and Kun Bu. "B-spline contour curve approximation and deformation analysis of complex ceramic core." Proceedings of the Institution of Mechanical Engineers, Part B: Journal of Engineering Manufacture 233, no. 6 (June 20, 2018): 1663–73. http://dx.doi.org/10.1177/0954405418782289.

Full text

Abstract:

Complex ceramic core is the critical part for manufacturing hollow turbine blade in the investment casting process. The complex geometry, small inner structures and high-precision requirements of ceramic cores make them difficult to fabricate, and the shape and dimensional accuracy of ceramic cores are very low in factory practice. To understand the deformation characteristics of ceramic cores, a noisy points recognition algorithm, an extraction method of measuring cross-section contour points and a B-spline iterative fitting algorithm using dominant points of chord deviation are proposed. First, the cross-section contour points were provided through registration, slicing and intersection methods. Second, the noisy points were deleted by convex noisy points and concave noisy points recognition algorithms. Third, the cross-section contour curve of the ceramic core was fitted through B-spline iterative fitting method with chord deviation dominant points. The curves fitted with chord deviation points and curves fitted with local maximum curvature points were compared with simulating data and scanning data, respectively, and the results show that B-spline fitting curve needs fewer chord deviation points than local maximum curvature points, 24.4% fewer in simulation validation and 12.5% fewer in experimental validation. In the end, the bending deformation, torsion deformation and shrinkage deformation errors of ceramic core are established by fitting contour curves of serial cross sections of the ceramic core.

APA, Harvard, Vancouver, ISO, and other styles

20

Moritz, Tassilo, and Hans Jürgen Richter. "Freeze Casting of Ceramic Components Using Ice Cores and Ice Moulds." Advances in Science and Technology 45 (October 2006): 391–96. http://dx.doi.org/10.4028/www.scientific.net/ast.45.391.

Full text

Abstract:

A novel shaping technique for advanced ceramic components is presented which allows manufacturing of complex ceramic components with enclosed cavities by using ice moulds or ice cores. Different suspensions of alumina and zirconia powders have been developed for this special freeze casting technique. The suspensions must meet following requirements: high solid content, the capability of flow, a freezing point between -10 and -2 °C, and a casting temperature below 0 °C. After the casting process the moulds and cores could be easily removed by sublimation. The suspension liquid was removed in the frozen state simultaneously. In this way very complicated hollow or filled structures such as metallic or ceramic components encapsulated in ceramic shells could be produced. No de-moulding was necessary, no solid core must be removed, and no liquid phase appeared as known from other lost-mould techniques. Ice mould casting is a very environmental-friendly shaping technique. Furthermore, the influence of dispersing agents, anti-freeze agents and of the freezing speed on the pore structure of the ceramic components has been investigated.

APA, Harvard, Vancouver, ISO, and other styles

21

Fan, Hong Na, Hui Ming Ji, Ding Zhong Tang, Xiao Guang Liu, Jian Sheng Yao, Xin Li, Guo Hong Gu, Li Li Wang, and Shu Xin Niu. "Effect of Mullite Content on the Properties of Silica-Based Ceramic Cores." Materials Science Forum 816 (April 2015): 262–65. http://dx.doi.org/10.4028/www.scientific.net/msf.816.262.

Full text

Abstract:

In this study, mullite was used as the addition to prepare silicon based ceramic cores, and the effect of mullite content on the mechanical and chemical properties was investigated. The phase composition and the morphology of the ceramic cores were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM) respectively. The results indicated that the shrinkage was induced by the addition of mullite and contaminations. The intensity of pre-heated cristobalite increased sharply with the mullite content increasing, which could improve the high temperature deformation simultaneously. However, mullite was difficult to remove by reacting with KOH which decreased the leaching rate of ceramic core. When mullite content was 15 wt%, the shrinkage of ceramic core was 0.78%, the creep at 1540 °C for 1 h was 0.3 mm and the leaching rate was 0.1 g/min, which meets the need of ceramic core of hollow turbine blades.

APA, Harvard, Vancouver, ISO, and other styles

22

Niu, Shu Xin, Ding Zhong Tang, Xiao Guang Liu, Jian Sheng Yao, Xin Li, Li Li Wang, Guo Hong Gu, Yin Ping Yang, and Xiao Wei Yang. "Effect of Pre-Added Cristobalite Content on the Properties of Silica-Based Ceramic Cores." Materials Science Forum 848 (March 2016): 217–21. http://dx.doi.org/10.4028/www.scientific.net/msf.848.217.

Full text

Abstract:

In this study, cristobalite was used as the addition to prepare silica based ceramic cores, and then the effect of cristobalite content on the mechanical and chemical properties was investigated. The increasing of pre-added cristobalite content resulted in more crystallized cristobalite in the sintered samples and the variation of the linear shrinkage and mechanical properties. When pre-added cristobalite content was 6.0 wt%, the shrinkage of ceramic core was 0.42%, the creep at 1540°C for 30 min was 0.10 mm, and the flexural strength at room temperature and at 1550°C were 25.2 MPa and 28.7 MPa, respectively, which meets the need of ceramic cores of hollow turbine blades.

APA, Harvard, Vancouver, ISO, and other styles

23

Lu, Jiang Ren, Xin Li Sun, Xing Hui Cai, San Qiang Dong, and Guo Liang Wang. "Numerical Study on the Anti-Ballistic Properties of Metal Encapsulating Ceramic Composite Armors." Applied Mechanics and Materials 723 (January 2015): 26–30. http://dx.doi.org/10.4028/www.scientific.net/amm.723.26.

Full text

Abstract:

The impact responses and ballistic resistance of the metal encapsulating ceramic composite armors with same area density and two hybrid cores are investigated. The hybrid cores include square metallic lattice with ceramic block insertions, and square metallic lattice with ceramic ball insertions and void-filling epoxy resin. Three-dimensional (3D) finite element (FE) simulations are carried out for each composite armors impacted by bullet with 12.7mm diameter. The focus is placed on the energy absorption capabilities and ballistic limit velocity of different composite armors. Results indicate that two kind of armors can improve the ballistic resistance properties and save mass of 22% and 25% compared to the homogeneous 4340 steel, respectively.

APA, Harvard, Vancouver, ISO, and other styles

24

Widjono, Rani Aryani, Gita Winata, and Naomi Haswanto. "PENERAPAN INSTRUCTIONAL SYSTEM DESIGN (ISD) PADA PEMETAAN DAN VISUALISASI INFORMASI TEKNIK DASAR PEMBUATAN KERAMIK." Ultimart: Jurnal Komunikasi Visual 12, no. 2 (January 15, 2020): 41–52. http://dx.doi.org/10.31937/ultimart.v12i2.1441.

Full text

Abstract:

Ceramics Handmade in Jakarta currently has become a new hype. With hand- made ceramics people having a direct connection with the makers by how those things made. Techniques, materials, and the process are the reasons why people are more attracted to get involved by making their ceramics by themselves. The hype caused high demand of ceramic basic techniques information, but people barely find ceramic books or other types of media which commissioned and developed by the actual condition of Indonesia’s independent ceramics studio especially Jakarta. This study structured through Instructional System Design (ISD) by two main cores. The first is to formulate a mapping method to classify the information of ceramics techniques at a different level. The intention is to gather specific information for beginners that would apply on instructional media. The second is designing a media such as conventional books and virtual information video through the augmented book. The result construct augmented book with systematically measurable information. It provides people easy access information and offered a new learning experience by using the augmented book.

APA, Harvard, Vancouver, ISO, and other styles

25

Jiao, An Yuan, Feng Hui Wang, and Si Qing Yang. "Study on Making Ceramic Composite Steel Plate by SHS Process." Advanced Materials Research 299-300 (July 2011): 806–9. http://dx.doi.org/10.4028/www.scientific.net/amr.299-300.806.

Full text

Abstract:

Large cross-section composite rectangular steel tubes with ceramics inner liner, which can be used directly, and also cut into the ceramics clad plate, were made by a new effective way. The material type, shape and size parameters of cores were determined and thickness and hardness of the ceramic coating were measured. The bond stress between steel substrate and alumina ceramics were analyzed and the bond modes also were checked. The dimension parameters of hemming plate used in the experiment were determined and the bond strength between the coating and tube substrate in normal and tangential direction was examined. The results show that the ceramics coating surface is glossy, which thickness is among 1.5-3.5 mm, the hardness of alumina ceramics inner liner is above HV1100. Metallurgical bonding between steel substrate and ceramics coating could not come into being and the mechanical bonding with lower bonding force is the mainly joint mode.

APA, Harvard, Vancouver, ISO, and other styles

26

Lee, J. J. W., J. Y. Kwon, S. Bhowmick, I. K. Lloyd, E. D. Rekow, and B. R. Lawn. "Veneer vs. Core Failure in Adhesively Bonded All-ceramic Crown Layers." Journal of Dental Research 87, no. 4 (April 2008): 363–66. http://dx.doi.org/10.1177/154405910808700408.

Full text

Abstract:

Joining a brittle veneer to a strong ceramic core with an adhesive offers potential benefits over current fabrication methods for all-ceramic crowns. We tested the hypothesis that such joining can withstand subsurface radial cracking in the veneer, from enhanced flexure in occlusal loading, as well as in the core. Critical conditions to initiate fractures were investigated in model crown-like layer structures consisting of glass veneers epoxy-joined onto alumina or zirconia cores, all bonded to a dentin-like polymer base. The results showed a competition between critical loads for radial crack initiation in the veneers and cores. Core radial cracking was relatively independent of adhesive thickness. Zirconia cores were much less susceptible to fracture than alumina, attributable to a relatively high strength and low modulus. Veneer cracking did depend on adhesive thickness. However, no significant differences in critical loads for veneer cracking were observed for specimens containing alumina or zirconia cores.

APA, Harvard, Vancouver, ISO, and other styles

27

Park, Il Seok, Se Young Choi, Myung Hyun Lee, Dae Joon Kim, and Jung Suk Han. "All-Ceramic Fixed Partial Denture Cores Prepared Using Water-Based Alumina Tapes." Key Engineering Materials 284-286 (April 2005): 929–32. http://dx.doi.org/10.4028/www.scientific.net/kem.284-286.929.

Full text

Abstract:

Aqueous-based alumina tape, prepared using acrylate emulsion binder, was employed to form 3-unit all-ceramic anterior fixed partial denture core structures. Formability, linear shrinkage, and strength of the tape were optimized by adjusting tape composition to a/(a+b+p)=0.84 and b/(b+p)=0.5. Marginal fitness of the core framework was acceptable for clinical applications when more than two points on lingual side of core structure were placed to touch a plate during sintering. The 3-unit all-ceramic anterior fixed partial denture utilized ceramic tape has functioned successfully for 3 years without any loss of structural integrity and esthetics.

APA, Harvard, Vancouver, ISO, and other styles

28

Ainsley, Chris, N. Reis, and B. Derby. "Rapid Prototyping of Ceramic Casting Cores for Investment Casting." Key Engineering Materials 206-213 (December 2001): 297–300. http://dx.doi.org/10.4028/www.scientific.net/kem.206-213.297.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

Low, I. M., F. W. Lim, and S. S. Low. "Synthesis of highly leachable gel-derived alumina ceramic cores." Journal of Materials Science Letters 12, no. 20 (1993): 1570–73. http://dx.doi.org/10.1007/bf00627016.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

Wang, Rong Feng, De Ming Zhang, Ou Yang Zhuang, Hai Lin Xu, Wen Sheng Huang, and Da Ming Xie. "Effect of Y₂O₃ Content on the Properties of Alumina-Based Ceramic Cores." Applied Mechanics and Materials 488-489 (January 2014): 145–49. http://dx.doi.org/10.4028/www.scientific.net/amm.488-489.145.

Full text

Abstract:

A series of alumina cores with different content of yttria were prepared by sintered at 1450°C. The flexural strength at room temperature, high temperature deformation and shrinkage rate of alumina based ceramic core were determined. the phase evolution and microstructure were studied by scanning electron microscopy (SEM) ,X-ray diffraction (XRD).The optimal yttria content on the combined properties of these cores were discussed. The results explained that The Al2O3 particles reacted with some Y2O3 particles to form a polycrystalline composition 3Y2O3·5Al2O3 (YAG), which activated the lattice and promoted sintering. Most of yttria, however, were concentrated in the ceramic grain boundaries, playing a role in improving grain refinement and microstructure; the cores achieved the best comprehensive performance when the content of yttria was 10%.

APA, Harvard, Vancouver, ISO, and other styles

31

Yu, Jian Bo, Zhong Ming Ren, B. Q. Wang, and Y. W. Zhang. "Effect of Sintering Systems and Colloidal Silica Sols on the Mechanical Properties of Oriented Silica-Based Ceramic Core Materials." Advanced Materials Research 177 (December 2010): 418–20. http://dx.doi.org/10.4028/www.scientific.net/amr.177.418.

Full text

Abstract:

A series of silica -based ceramic cores sintered at 1150°C, 1200°C for different times were prepared, and this study compared the three-point bending strength of room temperature and 900°C with commercially available colloidal silica sols systems. Three-point bend specimens 60 × 10 × 4 mm were cast by vacuum hot pressing and tested in a special mechanical testing machine with high temperature test system of ceramics. The effect of sintering systems and colloidal silica sols on the mechanical properties of ceramic core was discussed. It could be concluded that specimens sintered at 1150°C for 5h have an obtainable maximum bending strength and those immersed in colloidal silica sols contents showed doubled bending strength in the present research.

APA, Harvard, Vancouver, ISO, and other styles

32

Lu, Rong Jian, Cheng Long Wang, Jing Cai Zou, Yuan Fu Yi, Long Quan Shao, Ning Wen, Bin Gu, Yi Han Liu, and Bin Deng. "Effect of Post-Core Materials on the Color Value of Four Dental All-Ceramic Cores." Key Engineering Materials 544 (March 2013): 396–400. http://dx.doi.org/10.4028/www.scientific.net/kem.544.396.

Full text

Abstract:

The aim of this study were to compare the color value of four kinds of dental all-ceramic cores (IPS e.max Press,Zenostar,Lava Zirconia and Upcera Zirconia) on three different post-core materials.All-ceramic core materials were made into samples at the diameter of 10mm and the thickness of 0.50.02mm.Their color value on the post-core material of noble metal,Co-Cr alloy and resin were respectively determined with chromatism instrument.It was showed that the color value of four all-ceramic cores were statistically different.IPS e.max Press was most obviously affected by post-core materials,while Upcera Zirconia the weakest.Lava Zirconia and Zenostar were influenced to a certain degree.In conclusion,non-mental post-core was preferable for IPS e.max Press,Upcera Zirconia was fit for any post-core materials.

APA, Harvard, Vancouver, ISO, and other styles

33

Traini, Tonino, Roberto Sorrentino, Enrico Gherlone, Federico Perfetti, Patrizio Bollero, and Ferdinando Zarone. "Fracture Strength of Zirconia and Alumina Ceramic Crowns Supported by Implants." Journal of Oral Implantology 41, S1 (July 1, 2015): 352–59. http://dx.doi.org/10.1563/aaid-joi-d-13-00142.

Full text

Abstract:

Due to the brittleness and limited tensile strength of the veneering glass-ceramic materials, the methods that combine strong core material (as zirconia or alumina) are still under debate. The present study aims to evaluate the fracture strength and the mechanism of failure through fractographic analysis of single all-ceramic crowns supported by implants. Forty premolar cores were fabricated with CAD/CAM technology using alumina (n = 20) and zirconia (n = 20). The specimens were veneered with glass-ceramic, cemented on titanium abutments, and subjected to loading test until fracture. SEM fractographic analysis was also performed. The fracture load was 1165 (±509) N for alumina and 1638 (±662) N for zirconia with a statistically significant difference between the two groups (P = 0.026). Fractographic analysis of alumina-glass-ceramic crowns, showed the presence of catastrophic cracks through the entire thickness of the alumina core; for the zirconia-glass-ceramic crowns, the cracks involved mainly the thickness of the ceramic veneering layer. The sandblast procedure of the zirconia core influenced crack path deflection. Few samples (n = 3) showed limited microcracks of the zirconia core. Zirconia showed a significantly higher fracture strength value in implant-supported restorations, indicating the role played by the high resistant cores for premolar crowns.

APA, Harvard, Vancouver, ISO, and other styles

34

Lee, J. J. W., Y. Wang, I. K. Lloyd, and B. R. Lawn. "Joining Veneers to Ceramic Cores and Dentition with Adhesive Interlayers." Journal of Dental Research 86, no. 8 (August 2007): 745–48. http://dx.doi.org/10.1177/154405910708600811.

Full text

Abstract:

Adhesive joining of veneers to cores offers potential simplicity and economy in the fabrication of all-ceramic crowns. We tested the hypothesis that resin-based adhesives can be used for such fabrication without compromising mechanical integrity of the crown structure. A simple test procedure for quantifying this hypothesis was proposed. A model glass veneer layer 1 mm thick (representative of porcelain), adhesively bonded onto a glass-like core substrate (ceramic or dental enamel), was loaded at its top surface with a hard sphere (occlusal force) until a radial crack initiated at the veneer undersurface. The critical loads for fracture, visually observable in the transparent glass, afforded a measure of the predisposition for the adhesive to cause veneer failure in an occlusal overload. Two adhesives were tested, one a commercial epoxy resin and the other a relatively stiff in-house-developed composite. The results confirmed that stiffer adhesives provide higher resistance to failure.

APA, Harvard, Vancouver, ISO, and other styles

35

Wu, Hai Hua, and Zi Fan Fang. "Development of an Indirect Solid Freeform Fabrication Process Based on Stereolithography and Gelcasting for Ceramic Casting Molds." Advanced Materials Research 189-193 (February 2011): 2581–85. http://dx.doi.org/10.4028/www.scientific.net/amr.189-193.2581.

Full text

Abstract:

In this paper, an indirect solid freeform fabrication (ISFF) process was developed to rapidly fabricate ceramic casting molds by combining stereolithography with gelcasting technology. To realize this method, the stereolithography apparatus was used to fabricate a resin mold, and then aqueous ceramic slurry was cast into the resin mold and in situ polymerized to form a wet green body of ceramic casting mold. Freeze drying, pyrolyzing and sintering completed the manufacturing route. Finally, the ceramic casting mold with complex ceramic cores was obtained, and a car radiator with deep grooves was produced to verify the validity and feasibility of the method.

APA, Harvard, Vancouver, ISO, and other styles

36

Wu, Hai Hua, Di Chen Li, and Yi Ping Tang. "Fabrication of Integral Core/Shell Ceramic Casting Mould for Hollow Turbine Blade." Applied Mechanics and Materials 248 (December 2012): 231–36. http://dx.doi.org/10.4028/www.scientific.net/amm.248.231.

Full text

Abstract:

The paper presents an integral core/shell fabrication of ceramic casting mould for hollow turbine blades by combining SL (Stereolithography) with gelcasting. This method could guarantee the positional accuracy between ceramic cores and shell, thus achieving the rapid fabrication of complex turbine blade castings. The paper focuses on the design of resin mould for gelcasting, the preparation of ceramic slurry, the pyrolysis of resin prototype and the sintering of ceramic green body. The feasibility and effectiveness of above mentioned method were verified through successful manufacturing of hollow turbine blades with double-walled structure.

APA, Harvard, Vancouver, ISO, and other styles

37

Liu, Xiao Guang, Xin Li, Ding Zhong Tang, Jian Sheng Yao, and Shu Xin Niu. "Effect of Bimodal Granularity Distribution on the Properties of Silica-Based Ceramic Cores." Materials Science Forum 898 (June 2017): 1724–31. http://dx.doi.org/10.4028/www.scientific.net/msf.898.1724.

Full text

Abstract:

In this work, the effects of the bimodal particle size distribution of fused silica on the properties of silica-based ceramic cores have been investigated. In order to simulate a casting process condition, the core specimens were sintered at 1220°C, tested at above 1500°C. Three point bending tests were carried out on all the prepared specimens. Phase evolution and microstructure were investigated by XRD and SEM respectively. The results showed that with the bimodal granularity distribution broaden and the content of coarse particles increasing, the contraction, flexural strength and creep deformation of ceramic cores decreased linearly, as the content of mineralizer was determined. Coarse particles served as the skeleton to relieve the contraction in ceramic matrix and avoided sharp decrease of flexural strength. The high temperature properties were largely determined by the combined effects of crystallization and skeleton network. The crystallization depended mostly on the fine particles, and the skeleton network was prerequisite to avoid creep deformation.

APA, Harvard, Vancouver, ISO, and other styles

38

HENRIQUES, Priscila Alonso, André Hayato SAGUCHI, Fábio Valverde Rodrigues BASTOS NETO, Igor PROKOPOWITSCH, and Angela Toshie ARAKI. "Fracture resistance of metal-ceramic crown copings cemented to two types of intra-radicular posts." Revista de Odontologia da UNESP 47, no. 5 (October 2018): 305–8. http://dx.doi.org/10.1590/1807-2577.09218.

Full text

Abstract:

Abstract Introduction Endodontically treated teeth are more susceptible to root fracture than vital teeth. In order to reduce the risk of fracture, the use of intra-radicular posts and crowns is indicated. However, their own fracture resistance remains unclear. Objective To analyze the behavior of metal-ceramic crown copings cemented to two types of intra-radicular posts under tensile stress. Material and method Sixteen metal-ceramic crown copings cemented with zinc phosphate cement to cast metal posts and cores (group 1, n = 8) or with self-adhesive resin cement to glass-fiber posts rebased with composite resin (group 2, n = 8) were subjected to tensile testing after endodontic treatment and standardized preparation. Failure occurred when the crown coping and/or post-core assembly fractured and/or detached. Result In group 1, after the application of a mean tensile load of 46.83 N, 7 crown copings and metal cores separated as a whole, while in 1 specimen the coping detached from the metal core. In group 2, a mean tensile load of 127.68 N resulted in glass-fiber post fracture, and in 1 case the entire crown-post-core assembly was detached. Tensile strength differed significantly between the two groups (p = 0.0085). Conclusion Our findings suggest that metal-ceramic crown copings cemented with self-adhesive resin cement show strong adhesion to composite resin cores associated with glass-fiber posts, thus providing a safe alternative to the use of cast metal posts and cores.

APA, Harvard, Vancouver, ISO, and other styles

39

Gkogkas, Evangelos, Panagiota T. Dalla, Theodore E. Matikas, and Simeon Agathopoulos. "Influence of Silane Treatment of All-Ceramic Surfaces (e-Max) on the Cementation with Tooth Dentine." Key Engineering Materials 758 (November 2017): 34–38. http://dx.doi.org/10.4028/www.scientific.net/kem.758.34.

Full text

Abstract:

The influence of the treatment of the surface of IPS Empress II (e-max) glass-ceramic dental material with different silane agents on the surface roughness of this glass-ceramic was evaluated. IPS Empress II (e-max) cores were treated with five different commercial silane agents used in dentistry nowadays, for several periods of time and were finally air dried. After silanization, the surfaces of the glass-ceramic cores were observed with a light profilometer, a scanning electron microscope (SEM), and an atomic force microscope (AFM). The values of surface roughness (Ra) were also measured with the light profilometer. The results showed an important effect of silane treatment applied for different periods of time, especially for prolonged treatment for 24 hours, on the surface roughness of IPS Empress II (e-max). These results can have an important impact on the deep understanding of the cementation protocols applied in modern dentistry.

APA, Harvard, Vancouver, ISO, and other styles

40

Yang, Zhigang, Kaili Li, Shiqing Ma, Jianbo Yu, and Zhongming Ren. "Preparation, mechanical, and leaching properties of CaZrO 3 ceramic cores." International Journal of Applied Ceramic Technology 18, no. 5 (February 18, 2021): 1490–97. http://dx.doi.org/10.1111/ijac.13726.

Full text

APA, Harvard, Vancouver, ISO, and other styles

41

Jia, Zhi Hong, Shun Cheng Wang, Ming Zhe Ma, Liang Xu, Yu Tao Zhao, De Xin Ma, and Xiang Zhu. "The Study on Properties of Soluble Alumina Based Ceramic Cores." Applied Mechanics and Materials 477-478 (December 2013): 1321–28. http://dx.doi.org/10.4028/www.scientific.net/amm.477-478.1321.

Full text

Abstract:

The effect of the sintering temperature, quartz and sodium phosphate content on the core strength,shrinking percentage and solubility of alumina matrix ceramic cores was investigated．The results show that：the more the quartz is, the higher of the bending, tensile strength at room temperature of core are;It has the extreme point when quartz is 10wt%, then decreases slightly.The shrinkage rate and the room temperature strength of core increases with the rising of sintering temperature,but decreases with the increasing of content of sodium phosphate. Furthermore, the effect of the sintering temperature,quartz powder and sodium phosphate content on solubility of core was discussed.

APA, Harvard, Vancouver, ISO, and other styles

42

Li, Qiaolei, Tianci Chen, Jingjing Liang, Chaowei Zhang, Jinguo Li, Yizhou Zhou, and Xiaofeng Sun. "Manufacturing of ceramic cores: From hot injection to 3D printing." Journal of Materials Science & Technology 134 (January 2023): 95–105. http://dx.doi.org/10.1016/j.jmst.2022.06.033.

Full text

APA, Harvard, Vancouver, ISO, and other styles

43

Huang, Shuangjun, Chunsheng Ye, Huoping Zhao, and Zitian Fan. "Additive manufacturing of thin alumina ceramic cores using binder-jetting." Additive Manufacturing 29 (October 2019): 100802. http://dx.doi.org/10.1016/j.addma.2019.100802.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Cova, Camilla Maria, Alessio Zuliani, Roberta Manno, Victor Sebastian, and Rafael Luque. "Scrap waste automotive converters as efficient catalysts for the continuous-flow hydrogenations of biomass derived chemicals." Green Chemistry 22, no. 4 (2020): 1414–23. http://dx.doi.org/10.1039/c9gc04091a.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Zhong, Jiangwei, and Qingyan Xu. "High-Temperature Mechanical Behaviors of SiO2-Based Ceramic Core for Directional Solidification of Turbine Blades." Materials 13, no. 20 (October 14, 2020): 4579. http://dx.doi.org/10.3390/ma13204579.

Full text

Abstract:

The high-temperature mechanical behaviors of SiO2-based ceramic cores for the directional solidification of turbine hollow blades were investigated. Isothermal uniaxial compression tests of ceramic core samples were conducted on a Gleeble-1500D mechanical simulator with an innovative auxiliary thermal system. The stress–strain results and macro- and micro- structures of SiO2-based ceramic cores were investigated experimentally. The microstructures were characterized by the scanning electron microscope (SEM). Based on the experimental data, a nonlinear constitutive model for high temperature compressive damage was established. The statistical results of Weibull moduli show that the stability of hot deformation increases with the increase of temperature. The fracture type of the SiO2-based core samples is brittle fracture, but when the temperature exceeds 1400 °C, the mechanical behavior exhibits thermo-viscoelastic and viscoplastic property. Under high-temperature (>1400 °C) and stress conditions, the strength of the ceramic core is weakened owing to the viscous slip of SiO2, which is initially melted at the temperature of 1400 °C. The comparison results between the predictions of nonlinear model and experimental values indicate that the model is applicable.

APA, Harvard, Vancouver, ISO, and other styles

46

Daou, Elie E. "The Zirconia Ceramic: Strengths and Weaknesses." Open Dentistry Journal 8, no. 1 (April 18, 2014): 33–42. http://dx.doi.org/10.2174/1874210601408010033.

Full text

Abstract:

Metal ceramic restorations were considered the gold standard as reliable materials. Increasing demand for esthetics supported the commercialization of new metal free restorations. A growing demand is rising for zirconia prostheses. Peer-reviewed articles published till July 2013 were identified through a Medline (Pubmed and Elsevier). Emphasizing was made on zirconia properties and applications. Zirconia materials are able to withstand posterior physiologic loads. Although zirconia cores are considered as reliable materials, these restorations are not problem free.

APA, Harvard, Vancouver, ISO, and other styles

47

Puntsag, O. E., E. K. Bae, Jae Hoon Lee, and Keun Woo Lee. "The Marginal Fit of CAD-CAM Zirconia Cores with Different Proximal Margin Configurations." Key Engineering Materials 330-332 (February 2007): 1409–12. http://dx.doi.org/10.4028/www.scientific.net/kem.330-332.1409.

Full text

Abstract:

This study evaluated the marginal fit of CAD-CAM Zirconia cores with different proximal height. Thirty Zirconia cores and ten metal ceramics crowns were used to evaluate the marginal gap. The marginal fit was determined to be perpendicular to the tooth axis between the most apical point on the coping margin (core) and the reference marks on the mesial, distal, labial, and palatal surfaces of the die at several key stages of crown fabrication; before porcelain built-up, after body porcelain built-up, and after glazing. Additionally, an opaque stage for the metal ceramic copings was compared as well. Each measurement was carried out with a microscope. The means of gaps among the groups were 58±27 -m, 69±23 -m, 89±29 -m and 80±28 -m, groups I, II, III and IV, respectively. In relation to the proximal and labiopalatal surfaces there were no statistical difference among the groups, except group I. No significant differences were observed in firing stages of all groups. The findings of this study showed that the mean marginal gap of Zirconia cores with different proximal heights fell well within the acceptable clinical ranges.

APA, Harvard, Vancouver, ISO, and other styles

48

Cornacchia, Giovanna, Daniele Dioni, Michela Faccoli, Claudio Gislon, Luigi Solazzi, Andrea Panvini, and Silvia Cecchel. "Experimental and Numerical Study of an Automotive Component Produced with Innovative Ceramic Core in High Pressure Die Casting (HPDC)." Metals 9, no. 2 (February 12, 2019): 217. http://dx.doi.org/10.3390/met9020217.

Full text

Abstract:

Weight reduction and material substitution are increasing trends in the automotive industry. High pressure die casting (HPDC) is the conventional casting technology for the high volume production of light alloys; it has recently found wide application in the manufacturing of critical components, such as complex and thin geometry automotive parts. However, the major restriction of this affordable technology is the difficulty to design and realize hollow sections or components with undercuts. An innovative way to further increase the competitiveness of HPDC is to form complex undercut shaped parts through the use of new lost cores that are able endure the high pressures used in HPDC. This paper investigates the use of innovative ceramic lost cores in the production of a passenger car aluminum crossbeam by HPDC. Firstly, process and structural simulations were performed to improve the crossbeam design and check the technology features. The results led to the selection of the process parameters and the production of some prototypes that were finally characterized. These analyses demonstrate the feasibility of the production of hollow components by HPDC using ceramic cores.

APA, Harvard, Vancouver, ISO, and other styles

49

Zhao, Guang, Kehui Hu, Qian Feng, and Zhigang Lu. "Creep mechanism of zircon-added silica ceramic cores formed by stereolithography." Ceramics International 47, no. 12 (June 2021): 17719–25. http://dx.doi.org/10.1016/j.ceramint.2021.03.092.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Znamenskii, L. G., O. V. Ivochkina, and T. V. Stepanova. "Manufacture of Ceramic Molds and Cores from Inorganic Materials Using Permanent." IOP Conference Series: Materials Science and Engineering 969 (November 13, 2020): 012070. http://dx.doi.org/10.1088/1757-899x/969/1/012070.

Full text

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Ceramic cores'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles