摘要
以MgSiN_(2)和Y_(2)O_(3)为烧结助剂,通过气压烧结法在氮气压力1.0 MPa、1 850℃和保温3 h条件下制备出Si_(3)N_(4)陶瓷。研究了MgSiN_(2)/Y_(2)O_(3)比例及添加量对Si_(3)N_(4)陶瓷气孔率、显微结构、力学性能和热导率的影响。结果表明:当MgSiN_(2)和Y_(2)O_(3)复合烧结助剂总含量不变时,随着Y_(2)O_(3)含量的增加,β-Si_(3)N_(4)棒状晶的发育更为充分且异常长大情况明显减少。当MgSiN_(2):Y_(2)O_(3)的摩尔比为5:2、烧结助剂总添加量为10.5%(摩尔分数)时,制备的Si3N4陶瓷综合性能最优,其抗弯强度为510 MPa、热导率为67.01 W·m^(-1)·K^(-1)。
Si_(3)N_(4)ceramics were prepared via gas pressure sintering under nitrogen pressure of 1.0 MPa at 1850℃for 3 h with Y_(2)O_(3)and MgSiN_(2)as sintering aids.The effects of Mg SiN_(2)/Y_(2)O_(3)mole ratio and their total amount on the porosity,microstructure,mechanical properties and thermal conductivity of Si3N4 ceramics were investigated.The results show that the growth of rod-likeβ-Si_(3)N_(4)grains was more sufficient and the growth of abnormal grain decreased with the increase of Y_(2)O_(3)content at the constant total content of MgSiN_(2)and Y2 O3.Si3N4 ceramics with the optimal properties were prepared at a molar ratio of MgSiN_(2):Y_(2)O_(3)of 5:2 and the total amount of sintering aids of 10.5%,having the bending strength and thermal conductivity of 510 MPa and 67.01 W·m-^(-1)·K^(-1),respectively.
作者
李聪
张博
胡加斌
汪胜和
史忠旗
LI Cong;ZHANG Bo;HU Jiabin;WANG Shenghe;SHI Zhongqi(State Key Laboratory for Mechanical Behavior of Materials,School of Materials Science and Engineering,Xi'an Jiaotong University,Xi'an 710049,China;State Grid Anhui Electric Power Co.,LTD,Hefei 230061,China)
出处
《硅酸盐学报》
EI
CAS
CSCD
北大核心
2021年第12期2556-2562,共7页
Journal of The Chinese Ceramic Society
基金
国家重点研发计划项目(2018YFB0905600)
国家电网有限公司总部科技项目(SGAH0000KJJS1900437)。
关键词
氮化硅
烧结助剂
抗弯强度
热导率
silicon nitride
sintering aids
fracture strength
thermal conductivity
