惰性碳源对两步反应烧结碳化硅陶瓷组织和性能的影响  

Influence of the inert carbon source on the microstructure and properties of two-step reaction-sintered silicon carbide ceramics

作　　者：潘鑫龙 张明君 王波[1] 杨建锋[1] PAN Xinlong;ZHANG Mingjun;WANG Bo;YANG Jianfeng(State Key Laboratory for Mechanical Behavior of Materials,Xi’an Jiaotong University,Shanxi Xi’an 710049,China)

机构地区：[1]西安交通大学金属材料强度国家重点实验室,西安710049

出　　处：《功能材料》2025年第1期1179-1183,1192,共6页Journal of Functional Materials

摘　　要：两步反应烧结可以降低反应烧结碳化硅中的残余硅含量,采用纳米炭黑为活性碳源,过量碳微球和金刚石分别为惰性碳源,通过两步反应烧结制备了碳化硅陶瓷,分析比较了两种惰性碳源的反应率,以及对碳化硅陶瓷力学性能和热学性能的影响。结果表明,在碳密度和烧结工艺条件相同的情况下,金刚石的反应率低于碳微球,制备的烧结体中残余硅较多。在1550℃保温6 h条件下,使用高硬度的金刚石为惰性碳源制备的碳化硅的显微硬度达(2488±133)HV,高于使用碳微球制备的碳化硅。但是由于使用金刚石为惰性碳源制备的烧结体中低导热的残余硅较多,导致使用金刚石制备碳化硅的导热系数较低,在1550℃保温6 h条件下为115 W·m-1·K-1,低于碳微球使用的碳微球。Two-step reaction sintering can reduce the residual silicon content in reaction-sintered silicon carbide.In this thesis,silicon carbide ceramics were prepared by two-step reaction sintering using nanocarbon black as the active carbon source,and excess carbon microspheres and diamond as the inert carbon source,respectively,and the reaction rates of the two inert carbon sources were analyzed and compared,as well as the effects on the mechanical and thermal properties of the silicon carbide ceramics.The results showed that the reaction rate of diamond was lower than that of carbon microsphere,and the residual silicon was more in the prepared sintered body under the same conditions of carbon density and sintering process.At 1550℃for 6 h,the microhardness of silicon carbide prepared by using high hardness diamond as the inert carbon source reache 2488±133 HV,which was higher than that of silicon carbide prepared by using carbon microspheres.However,due to the high amount of low thermal conductivity residual silicon in the sintered body prepared using diamond as the inert carbon source,the thermal conductivity of the diamond-prepared silicon carbide 115 Wm·K at 1550℃for 6 h,which was lower than that of carbon microspheres used.

关 键 词：反应烧结碳化硅 碳源 两步反应烧结 残余硅 

分 类 号：TB32[一般工业技术—材料科学与工程]