挤压铸造MULLITE_F/M124F复合材料性能分析  

Behavior of Short Mullite Fibre Reinforced M124F Composites by Squeezing Casting

作　　者：张海涛[1] 吴申庆[2] 余式昌[2] 

机构地区：[1]安徽工程科技学院 [2]东南大学

出　　处：《特种铸造及有色合金》2006年第2期98-100,共3页Special Casting & Nonferrous Alloys

摘　　要：用挤压铸造工艺制备了莫来石短纤维(MULLITEF)增强马勒124合金(M124F)铝基复合材料,研究了该复合材料从室温到400℃高温的拉伸性能及热膨胀性能。试验结果表明,体积分数为17%的MULLITEF增强复合材料的300℃高温极限抗拉强度为228MPA,比其他短纤维或晶须增强相铝基复合材料提高15%以上;热膨胀系数(CTF)为16.5×10-6K。通过对3种试样的拉伸行为及SEM断口观察,分析了复合材料的静载破断机制,表明裂纹源主要生成于增强纤维与基体的复合界面上。Low volume fraction of short mullite fibers reinforced aluminum/silicon (M124F) alloys were prepared by the squeezing-casting process.The hardness,thermal expansion coefficient and the tensile strength of the composites were investigated from room temperature to 400 ℃.It is found that the tensile strength of the composites at room temperature is somewhat inferior to that of the M124F alloy.However,mullite fibers exert a beneficial effect on improving the tensile strength of M124F alloy at higher temperatures by more than 15% compared with other fibre reinforced composites.The fracture morphology of the composites specimens is observed with SEM to show the failure mechanism of the composite,where micro-crack is propagated in the interface between reinforced fibre and the matrix.

关 键 词：挤压铸造 Mullitef 铝基复合材料 性能 

分 类 号：TG249.2[金属学及工艺—铸造]