粒度组成对高体积分数SiC_p/Al复合材料性能的影响  

Effect of granularity modulation of SiC particulates on properties of high volume SiC_p/Al composites

作　　者：刘君武[1] 李青鑫[1] 吴金方[1] 丁锋[1] 郑治祥[1] 

机构地区：[1]合肥工业大学材料科学与工程学院,安徽合肥230009

出　　处：《材料热处理学报》2011年第3期14-18,共5页Transactions of Materials and Heat Treatment

基　　金：安徽省自然科学基金资助项目(090414187)

摘　　要：采用凝胶注模法制备SiC预制件用于无压熔渗液态铝合金实现60～67 vol%SiCp/Al复合材料的近净成形制备,研究了碳化硅颗粒级配及热处理对复合材料力学和热学性能的影响。结果表明:不同粒度的SiC粉体在铝基体中分布均匀,无明显偏聚现象;采用较细的SiC颗粒级配和退火处理都能有效提高复合材料强度;粗颗粒级配能增大SiC在复合材料中的体积分数,有利于导热性能的提高和热膨胀系数的降低;SiCp/Al复合材料抗弯强度介于240～365 MPa,室温时热导率介于122～175 W.m-1.℃-1之间,室温至250℃的平均线热膨胀系数小于7.5×10-6℃-1,满足电子封装的性能要求。60-67 vol% SiCp/Al composites with near-net-shape were obtained by pressureless infiltration of liquid aluminum alloy into SiC preforms prepared by gelcasting process.The effects of SiC granularity modulation and heat treatment on mechanical and thermal properties of SiCp/Al composites were studied.The results show that SiC particles with different granularity distribute evenly in aluminum matrix without obvious conglomeration.Strength of the composites is improved by finer SiC granularity modulation and annealing treatment.Higher SiC volume fraction in the composites is obtained by coarse granularity modulation,which is beneficial to the increase of thermal conductivity and the decrease of thermal expansion coefficient of SiCp/Al composites.Bending strength of the composites is in the range of 240 to 365 MPa,and its thermal conductivity at room temperature is in the range 122 to 175 W.m-1.k-1.Mean linear coefficient of thermal expansion of the composites from room temperature to 250 ℃ is less than 7.5 × 10-6 ℃-1,which satisfies the requirement of electronic packaging.

关 键 词：SICP/AL 凝胶注模 粒度级配 热导率 热膨胀系数 

分 类 号：TB333[一般工业技术—材料科学与工程]