Si粉对B_4C放电等离子烧结性能和力学性能的影响  

Influence of Silicon Addition on the Sintering Behavior and Mechanical Properties of Boron Carbide by SPS Process

作　　者：魏红康[1] 赵林[1] 汪长安[2] 尉磊[2] 朗莹[2] 

机构地区：[1]景德镇陶瓷学院,江西景德镇333000 [2]清华大学 新型陶瓷与精细工艺国家重点实验室,北京100084

出　　处：《稀有金属材料与工程》2013年第S1期329-331,共3页Rare Metal Materials and Engineering

基　　金：国家自然科学基金(51102120;51202097);清华大学新型陶瓷与精细工艺国家重点实验室开放课题;江西省教育厅青年自然科学基金

摘　　要：以Si粉为烧结助剂,采用放电等离子烧结工艺,在1600℃/50MPa下制备出了SiC/B4C陶瓷基复合材料。研究了Si添加量和保温时间对B4C基体SPS烧结性能和力学性能的影响。借助X射线衍射和扫描电镜分析了复合材料的物相组成和微观结构。结果表明:Si粉与B4C基体中的C发生反应,生成SiC相。Si粉的添加可以显著提高复合材料的烧结性能和力学性能。当Si添加量为20%时(质量分数,下同),复合材料的维氏硬度和抗弯强度分别可以达到43.46GPa和529.3MPa。致密度的提高以及断裂模式的转变是复合材料力学性能提高的主要原因。SiC/B4C ceramic matrix composites were prepared by spark plasma sintering at 1600 ℃ and 50 MPa. The effects of silicon addition and holding time on sintering property and mechanical properties of B4C were studied. Phase composition and microstructure of the composites were analyzed by XRD and SEM. The results indicate that silicon powder reacts with carbon originating in the B4C phase and forms a new phase of SiC. The addition of silicon powder can improve the sintering property and mechanical properties of B4C significantly. For the specimen with 20 wt% silicon, Vickers hardness of 43.46 GPa and flexural strength of 529.3 MPa are obtained. The improvement in mechanical properties is attributed to the high relative density and the change of fracture mode by the formation of the SiC phase.

关 键 词：碳化硼 硅粉 放电等离子烧结 力学性能 烧结性能 

分 类 号：TQ174.1[化学工程—陶瓷工业]