【摘要】 以Mo粉、W粉、Si粉和C粉为原料,采用原位反应高温热压一次复合工艺制备了不同配比的SiCp/(Mo,W)Si2复合材料。采用光学显微镜、扫描电镜和X射线衍射仪研究了其显微结构,并测定了其力学性能。结果表明,SiCp/(Mo,W)Si2复合材料中的增强相SiC颗粒分布在基体MoSi2的晶界和晶内,WSi2固溶于MoSi2,起到了协同强化的作用,强化效果比单独加入SiC或WSi2更为显著。该种复合材料的抗弯强度最高达到592 MPa,断裂韧性达到5.9 MPa.m1/2,维氏硬度达到19.4 GPa,分别比相同工艺制备的纯MoSi2提高了约5倍、2.1倍和2.2倍。更多还原

【Abstract】 We are among the first in China to study in situ synthesized composites of SiCp/(Mo,W)Si2.We now present our research results on in situ synthesized SiCp/(Mo,W)Si2 composites,which are expected to be highly promising for application in China.In the full paper,we explain in some detail our research results and their analysis.In this abstract,we just add some pertinent remarks to listing the two topics of explanation.The first topic is: the experimental methods.The three subtopics of the first topic are: the preparation of the test specimens(subtopic 1.1),the analysis of microstructure(subtopic 1.2) and the measurement of mechanical properties(subtopic 1.3).The second topic is: the results and discussion.The three subtopics of the second topic are: the microstructure and phases of in situ synthesized composites(subtopic 2.1),the mechanical properties at room temperature(subtopic 2.2) and the discussion and analysis(subtopic 2.3).In subtopic 2.1,we give three figures as results;the main result is that,in the SiCp/(Mo,W)Si2 composites,the reinforcement SiC is distributed around and in the grains of matrix MoSi2,and WSi2 is dissolved into the MoSi2.In subtopic 2.2,the measurement results are summarized in a table.In subtopic 2.3,additional items that we discuss and analyze are given in two figures and one table.Still in subtopic 2.3,we give the main results of our analysis as:(1) the co-strengthening of SiC and WSi2 makes the mechanical properties of the SiCp/(Mo,W)Si2 composites much better;(2) the flexural strength of 592 MPa,fracture toughness of 5.9 MPa(m1/2 and Vicker’s hardness of 19.4 GPa were respectively measured for the composites,which are about 5,2.1 and 2.2 times respectively higher than those of pure MoSi2 synthesized by the same process.更多还原