β-Si_3N_4含量对Y_2O_3-MgO-α-Si_3N_4陶瓷性能的影响

Effect of β-Si_3N_4 Content on Y_2O_3-MgO-α-Si_3N_4 Properties

利用扫描电子显微分析等手段,研究了棒状β-Si3N4含量对Y2O3-MgO-α-Si3N4陶瓷致密度、力学性能和显微结构的影响,确定了β-Si3N4和α-Si3N4的适宜配比。结果显示:随着β-Si3N4含量的增加,Y2O3-MgO-α-Si3N4陶瓷材料致密度和力学性能均先增加后降低,当β-Si3N4含量达到40%时,陶瓷致密度和力学性能同时达到最大,此时致密度为93%,横向断裂强度为583.4 MPa,断裂韧性为5.42 MPa.m1/2。

The influence of bar-shaped β-Si3N4 content on the density, mechanical property and microstructure of Y2O3-MgO-α-Si3N4 was researched by using SME and other methods, and the most appropriate proportion of β-Si3N4 to α-Si3 N4 was determined. The results showed that with the increasing of the content of β-Si3N4 both of the density and mechanical property of Y2O3-MgO-α-Si3N4 ceramic material first increased, then decreased. When β-Si3N4 content achieved 40%, the density and mechanical property both reached to the maximum, with a density of 93%, transverse rupture strength of 583.4 MPa and fracture toughness of 5.42 MPa·m^1/2