Effects of nano-SiC_p content on microstructure and mechanical properties of SiC_p/A356 composites assisted with ultrasonic treatment  

纳米SiC_p含量对超声方法制备的SiC_p/A356复合材料组织和性能的影响（英文）

作　　者：Kun HU Du YUAN Shu-lin Lü Shu-sen WU 胡坤;袁渡;吕书林;吴树森(华中科技大学材料成形与模具技术国家重点实验室,武汉430074)

机构地区：State Key Laboratory of Materials Processing and Die ＆ Mould Technology,Huazhong University of Science and Technology,Wuhan 430074,China

出　　处：《Transactions of Nonferrous Metals Society of China》2018年第11期2174-2181,共8页中国有色金属学报（英文版）

基　　金：Project(51574129)supported by the National Natural Science Foundation of China;Project(2016209A001)supported by JCKY Foundation,China

摘　　要：nano-SiCp/A356 composites with different nano-SiCp contents were prepared by squeeze casting after ultrasonic treatment（UT）. The effects of SiCp content on the microstructure and mechanical properties of the nanocomposites were investigated. Theresults show that with the addition of nano-SiCp, the microstructure of nanocomposites is obviously refined, the morphology of theα（Al） grains transforms from coarse dendrites to rosette crystals, and long acicular eutectic Si phases are shortened and rounded. Themechanical properties of 0.5%, 1% and 2% （mass fraction） SiCp/A356 nanocomposites are improved continuously with the increaseof nano-SiCp content. Especially, when the SiCp content is 2%, the tensile strength, yield strength and elongation are 259 MPa,144 MPa and 5.3%, which are increased by 19%, 69% and 15%, respectively, compared with those of the matrix alloy. Theimprovement of strength is attributed to mechanisms of Hall？Petch strengthening and Orowan strengthening.采用超声处理和挤压铸造制备具有不同纳米Si C颗粒含量的复合材料,并研究Si Cp含量对纳米复合材料显微组织和力学性能的影响。结果表明,随着纳米颗粒的加入,显微组织明显细化,α(Al)晶粒形貌由粗大枝晶向玫瑰晶转变,长针状共晶硅逐渐变短并且圆整。随着颗粒含量的增加,复合材料的抗拉强度、屈服强度和伸长率均持续增加。特别是,当Si C加入量达到2%(质量分数)时,抗拉强度、屈服强度和伸长率分别为259 MPa、144 MPa和5.3%,与基体合金相比分别增加19%、69%和15%。强度的提升是由于Hall-Petch强化和Orowan强化。

关 键 词：nano-SiCp aluminum matrix composites ultrasonic treatment microstructure mechanical properties 

分 类 号：TB333[一般工业技术—材料科学与工程]