Effect of TiN Addition on the Low Temperature Degradation of Ceramic Tool Materials 3Y-TZP

Ceramic tool materials, 3Y-TZP added by TiN particles, were fabricated through hot-pressing techniques. The effects of TiN on their low-temperature degradation at 220# in air were investigated. It is shown that TiN can improve the stability of t-ZrO2 and inhibit the transformation from tetragonal to monoclinic phase, and that the content of TiN affects the stability of tetragonal phase and the propagation of tetragonal-to-monoclinic transformation into the specimen interiors. It is suggested that the grain-boundary phase prevents the nucleation of transformation, and that the high elastic modulus of TiN can prevent the propagation of phase transformation by resisting the volume expansion of transformation. When the content of TiN is 20wt%, the ceramic material shows better low temperature degradation resistance.

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Magnetic properties evolution with grain boundary phase transformation and their growth in Nd-Fe-Cu-Ga-B sintered magnet during post-sinter annealing process

Intermetallics ◽

10.1016/j.intermet.2021.107303 ◽

2021 ◽

Vol 137 ◽

pp. 107303

Author(s):

Song Fu ◽

Xiaolian Liu ◽

Jiaying Jin ◽

Zhiheng Zhang ◽

Yongsheng Liu ◽

...

Keyword(s):

Magnetic Properties ◽

Phase Transformation ◽

Grain Boundary ◽

Annealing Process ◽

Boundary Phase ◽

Sintered Magnet

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Influence of Low Temperature Aging on the Flexural Strength of Y-TZP Ceramics

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.512-515.1756 ◽

2012 ◽

Vol 512-515 ◽

pp. 1756-1760 ◽

Cited By ~ 1

Author(s):

Chen Wang ◽

Li Min Dong ◽

Yuan Fu Yi ◽

Ning Wen ◽

Qing Feng Zan ◽

...

Keyword(s):

Phase Transition ◽

Phase Transformation ◽

Low Temperature ◽

Flexural Strength ◽

Monoclinic Phase ◽

Accelerated Aging ◽

Strength Increase ◽

Low Temperature Aging ◽

Temperature Aging

Low temperature aging (LTD) is an important factor of Y-TZP ceramic as artificial joint femoral head and dental restorative materials in vivo for long-term application. In this paper, the accelerated aging experiments on Y-TZP ceramics were conducted. The t-m phase transition is occurring from the surface to the inside during low temperature aging of Y-TZP ceramics. As content of phase transformation increases, thickness of phase transformation layer increases. While the content of surface monoclinic phase is less, the volume expansion and surface stress caused by phase transformation can make cracks and holes shrink or even close, then the flexural strength increase. As a large number of surface monoclinic phase was generated, due to there are a lot of microscopic defects in the phase transition layer, crystals loose, strength of grain boundary lower than that of not aging area and phase transformation layers fracture in the intergranular mode, that damages the flexural strength. Therefore, the flexural strength increase firstly and then decrease with the increase of surface monoclinic content.

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Simulation of Fracture Behavior in the Microstructure of Ceramic Tool Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.457-458.89 ◽

2012 ◽

Vol 457-458 ◽

pp. 89-92

Author(s):

Ting Ting Zhou ◽

Chuan Zhen Huang ◽

Han Lian Liu ◽

Jun Wang ◽

Bin Zou ◽

...

Keyword(s):

Finite Element ◽

Grain Boundary ◽

Fracture Resistance ◽

Fracture Behavior ◽

Single Phase ◽

Voronoi Tessellation ◽

Element Model ◽

Cohesive Element ◽

Ceramic Tool ◽

Tool Materials

In the paper, the Voronoi tessellation model is used to represent the microstructure of ceramic tool materials. And a finite element model based on cohesive element method has been developed to investigate the fracture behavior of the microstructure. The influences of mesh densities and cohesive parameters on the cracking patterns have been discussed. It is found that the enhancement of the grain boundary strength is beneficial for raising the fracture resistance of single-phase ceramic tool materials.

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Correlations between sintering conditions and microstructure in ceramics of composition Li0.80Mg0.20 (Ta0.80Ti0.20)O3

Journal of Materials Research ◽

10.1557/jmr.1988.0387 ◽

1988 ◽

Vol 3 (2) ◽

pp. 387-391 ◽

Cited By ~ 3

Author(s):

J. P. Bonnet ◽

J. Ravez ◽

Joo GiTae ◽

P. Hagenmuller

Keyword(s):

Low Temperature ◽

Grain Boundary ◽

Boundary Phase ◽

Closed Porosity ◽

Large Size ◽

Different Types ◽

Small Grains ◽

Sintering Conditions ◽

Sintering Processes ◽

Textural Change

Two quite different types of microstructures have been detected for MgTiO3-enriched LiTaO3 ceramics corresponding either to small size grains and open porosity or to large size grains with closed porosity and appearance of microcracks. The first structure appears in short sintering processes at relatively low temperature. The textural change is explained by transitory formation of a grain boundary phase that leads to quick coalescence of the small grains.

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