SiC晶须对SiBCN基陶瓷复合材料性能的影响  

Effect of SiC whisker on properties of SiBCN based ceramic composites

作　　者：魏玮 刘伟 李麒 曹腊梅 WEI Wei;LIU Wei;LI Qi;CAO Lamei(National Key Laboratory of Advanced High Temperature Structural Materials,AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China;National Key Laboratory of Advanced Composites,AECC Beijing Institute of Aeronautical Materials,Beijing 100095,China)

机构地区：[1]中国航发北京航空材料研究院先进高温结构材料重点实验室,北京100095 [2]中国航发北京航空材料研究院先进复合材料重点实验室,北京100095

出　　处：《材料工程》2023年第5期138-145,共8页Journal of Materials Engineering

基　　金：中国航空发动机集团产学研合作项目(HFZL2019CXY015)。

摘　　要：采用超声结合球磨混料的工艺,在由聚硼硅氮烷(PSNB)裂解得到的SiBCN陶瓷中引入SiC晶须。研究了不同质量分数SiC晶须对SiBCN陶瓷基复合材料密度、硬度、弯曲强度及微观结构的影响。结果表明:随着SiC晶须添加质量分数由0%提高至25%,复合材料的密度先降后升,开孔率逐步上升,材料硬度逐渐下降,弯曲强度先升后降再升;SiC晶须质量分数为5%的SiC_(w)/SiBCN复合材料弯曲强度可达191 MPa,与未添加晶须的SiBCN纯基体弯曲强度(60 MPa)相比提升218%;XRD分析发现晶须的引入对烧结后复合材料的物相组成影响不大;观察材料断口微观形貌发现,晶须在基体中的存在方式主要有桥联和团聚搭桥两种,其中桥联有利于强化材料而团聚搭桥则会在基体内部形成孔隙进而降低材料强度。SiC_(w)hisker was added into SiBCN ceramics obtained by pyrolysis of polyborosilazane(PSNB)by ultrasonic combined with ball milling.The effects of different mass fractions SiC_(w)hisker on the density,hardness,bending strength and microstructure of SiBCN ceramic matrix composites were studied.The results show that with the mass fraction of SiC_(w)hisker increasing from 0%to 25%,the density of the composite is first decreased and finally increased,the porosity is gradually increased,the hardness is gradually decreased,and the bending strength is first increased,then decreased and finally increased;It was found that the three-point bending strength of SiC_(w)/SiBCN composite with 5%SiC_(w)hisker can reach 191 MPa,which is 218% higher than that of pure SiBCN matrix without whisker(60 MPa).XRD analysis shows that the introduction of whiskers has little effect on the phase composition of sintered composites;by observing the micro morphology of the fracture surface of the materials,it was found that the existence modes of whiskers in the matrix mainly include bridging and agglomeration bridging.Bridging whiskers are conducive to strengthening the material,while agglomerated whiskers will form pores in the matrix,so as to reduce the strength of the material.

关 键 词：SiBCN陶瓷 SIC晶须 材料性能 SiC_(w)/SiBCN复合材料 

分 类 号：TB332[一般工业技术—材料科学与工程]