光固化后用气压烧结Si3N4陶瓷的显微组织和力学性能影响

Microstructure and Mechanical Properties of Air Pressure Sintering Si3N4 Ceramics after Photocuring

选用CeO2和Yb2O3两种不同的烧结助剂,用光固化后气压烧结制备了高致密的Si3N4陶瓷材料。在相同的烧结温度下,用CeO2烧结试样中的β-Si3N4的晶粒尺寸比用Yb2O3为烧结助剂制备的试样的晶粒尺寸要大。其中:在1750℃,10 MPa条件下制备出了致密度到>95.8%Si3N4基陶瓷,力学性能分别为:σmax=715.83±15.26 MPa、HV=14.16±0.43 MPa、KIC=8.03 MPa·m^1/2。

In this paper,two different sintering aids,CeO2 and Yb2O3,were selected to prepare high-density Si3N4 ceramic materials by light curing and gas pressure sintering.At the same sintering temperature,the grain size ofβ-Si3N4 in the sample sintered with CeO2 is larger than that of the sample prepared with Yb2O3 as the sintering aid.Among them:Si3N4-based ceramics with a density of>95.8%were prepared under the conditions of 1750℃and 10 MPa.The mechanical properties are respectively:σmax=715.83±15.26 MPa,HV=14.16±0.43 MPa,KIC=8.03 MPa·m1/2.