Investigation of Thermal Shock Behaviors for Machinable SiC/h-BN Ceramic Composites

2007 ◽  
Vol 544-545 ◽  
pp. 391-394 ◽  
Author(s):  
Hai Yun Jin ◽  
Guan Jun Qiao ◽  
Ji Qiang Gao
Keyword(s):  
Fracture Toughness ◽  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Bending Strength ◽  
Ceramic Composites ◽  
The Matrix ◽  
Shock Resistance

The SiC/h-BN ceramic composites with different h-BN size were fabricated by Plasma Active Sintering (PAS) method. For the SiC/ nano-sized h-BN ceramic composites, when the h-BN content was increased, because the nano-sized h-BN crystals were homogeneously dispersed around the SiC grains of the matrix, the bending strength and fracture toughness of the composites decreased slowly, but the hardness decreased sharply, therefore the machinability and thermal shock resistance were improved noticeable.

Thermal Shock Behavior of Calcia Stabilized Zirconia Ceramics with Porosity Gradient Structure

2009 ◽  
Vol 631-632 ◽  
pp. 435-440
Author(s):  
Qiang Shen ◽  
Chang Lian Chen ◽  
Fei Chen ◽  
Qi Wen Liu ◽  
Lian Meng Zhang
Keyword(s):  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Bending Strength ◽  
Gradient Structure ◽  
Monoclinic Zirconia ◽  
Stabilized Zirconia ◽  
Zirconia Ceramics ◽  
The Matrix ◽  
Shock Resistance ◽  
Thermal Shock Behavior

Porous calcia stabilized zirconia ceramics (CSZC) with closed pores were presurelessly sintered by adding different contents of zirconia hollow balls. CSZC FGM with porosity gradient structure was then fabricated by laminating five layers with designed contents of zirconia hollow balls. The porosity, microstructure, and bending strength of the obtained CSZC samples were characterized. The results show that the hollow balls distribute uniformly and are well bonded with the matrix, and the porous structure is mainly composed of closed pores. The porosity of the CSZC increases linearly from 5.7 % to 31.6 % when the content of zirconia hollow balls increases from 0 % to 30 %, and the bending strength decreases rapidly from 297 MPa to 30 MPa. The thermal shock behavior of the CSZC and FGM was evaluated using air-quenching technique. It is shown that the residual bending strength of the quenched samples increases after several quenching cycles, and the samples are damaged by thermal shock after eight thermal cycles because of the production of monoclinic zirconia. FGM samples with porosity gradient structure can endure above twelve thermal shock cycles and exhibits better thermal shock resistance.

scholarly journals High Temperature Bending Strength and Thermal Shock Resistance of Carbon-Ceramics Composites

TANSO ◽  
1985 ◽  
Vol 1985 (120) ◽  
pp. 21-27 ◽  
Author(s):  
Kenji Miyazaki ◽  
Hisayoshi Yoshida ◽  
Kazuo Kobayashi
Keyword(s):  
High Temperature ◽  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Bending Strength ◽  
Shock Resistance

Effect of AlF3 Content on Microstructure and Properties of Mullite/Al2O3 Composite Ceramics

2018 ◽  
Vol 922 ◽  
pp. 62-67
Author(s):  
Ke Zheng Sang ◽  
Fan Wang ◽  
De Jun Zeng ◽  
Hong Wei Li
Keyword(s):  
Fracture Toughness ◽  
Flexural Strength ◽  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Diameter Ratio ◽  
Pressureless Sintering ◽  
Composite Ceramics ◽  
Microstructure And Properties ◽  
Shock Resistance ◽  
Mullite Whiskers

To reinforce the mullite/Al2O3 composite ceramics through formation of mullite whiskers, the composite ceramics were prepared by pressureless sintering using different AlF3 content. The microstructure, porosity, fracture toughness and thermal shock resistance of the composite ceramics were investigated. The results show that the addition of AlF3 can promote the mullite whisker formations, and the whiskers with the size of 3～10μm in diameter and a length-diameter ratio of 10～15 are obtained by sintering at 1600°C with the AlF3 content of 5wt%. Fracture toughness and thermal shock resistance of the composite ceramics are improved by the formation of mullite whisker. The fracture toughness of 4.79MPa•m1/2 can be obtained, and the 95.18% flexural strength remained after thermal shock.

Thermal shock resistance and fracture toughness during the graphitization process

Carbon ◽  
1981 ◽  
Vol 19 (2) ◽  
pp. 111-118 ◽  
Author(s):  
S. Sato ◽  
K. Kawamata ◽  
H. Awaji ◽  
M. Osawa ◽  
M. Manaka
Keyword(s):  
Fracture Toughness ◽  
Thermal Shock ◽  
Thermal Shock Resistance ◽  
Shock Resistance

Influence of Additives on Performance of Silicon Carbide Refractory

2012 ◽  
Vol 538-541 ◽  
pp. 2277-2280
Author(s):  
You Fu Guo ◽  
Ming Yue Zheng ◽  
Jing Long Bu ◽  
Yue Jun Chen ◽  
Li Xue Yu ◽  
...  
Keyword(s):  
Silicon Carbide ◽  
Thermal Expansion ◽  
Bulk Density ◽  
Thermal Shock ◽  
Silica Fume ◽  
Thermal Shock Resistance ◽  
Bending Strength ◽  
Carbide Refractory ◽  
Shock Resistance ◽  
Silicon Carbide Refractory

Silicon carbide with diffierent granularity was used as raw material, quartz, silica fume, aluminum powder or alumina was used as additive with dosages of 1% (in mass, similarly hereinafter), 3% and 5%. Silicon carbide refractory material was prepared in oxidizing atmosphere at 1400 °C for 3 h. Performence of samples were researched by measurements of apparent porosity, bulk density, bending strength at room temperature, thermal shock resistance and thermal expansion rate, and analyzed by SEM. The results showed that samples added silica fume have low thermal expansion rate and apparent porosity, high bending strength and bulk density, good thermal shock resistance, compact texture as well. It can be deduced that 5% silica fume plays the excellent role to improve integrated performance of silicon carbide refractory material.

Sign in / Sign up

Export Citation Format

Share Document