Effect of Z Values on the Microstructure and Mechanical Properties of Post-sintered Reaction Bonded β-SiAlON

High Temperature Materials and Processes

卷:36

Li Yanjun¹  Ding Donghai¹  Xiao Guoqing¹  Liu Donghua¹  Jin Han²  Jin Zhihao²  Shi Zhongqi² 

[1] College of Materials and Mineral Resources, Xi’an University of Architecture and Technology, Xi’an710055, China;

[2] State Key Laboratory for Mechanical Behavior of Materials, Xi’an Jiaotong University, Xi’an710049, China;

关键词: sialon;    reaction bonding;    post-sintering;    mechanical properties;   

DOI  :  10.1515/htmp-2015-0256

来源: DOAJ

【 摘 要 】

β-SiAlON materials with different Z values (Z=0.5–3) were fabricated by a reaction bonding combining post-sintering route using raw materials of Si, Al2O3, AlN, etc. The reaction bonded β-SiAlON (RB-β-SiAlON) were post-sintered at 1,750 °C for 6 h. Apparent porosity, bulk density, bending strength and Vicker’s hardness of the samples before and after post-sintering were tested. XRD results showed that the phase composition of both RB-β-SiAlON and post-sintered RB-β-SiAlON (PSRB-β-SiAlON) were β-SiAlON. For RB-β-SiAlON, the apparent porosity was decreased with the increase of Z values, while the strength and hardness was increased accordingly. After the post-sintering procedure, nearly full densified PSRB-β-SiAlON was obtained and the mechanical properties were significantly improved. The bending strength and Vicker’s hardness of the PSRB-β-SiAlON (Z=0.5) achieved 510 MPa and 16.5 GPa, respectively, which were as 2.7 and 6.7 times high as those of the corresponding RB-β-SiAlON. However, the strength and hardness of PSRB-β-SiAlON decreased with the increase of Z value due to the grain growth.

【 授权许可】

Unknown