SiC_(p)/2024Al复合材料板材的显微组织、力学性能及加工硬化行为  

Microstructure, mechanical properties and work hardening behavior of SiC_(p)/2024Al composite sheet

作　　者：薛鹏鹏 曹富翔 邓坤坤[1] 聂凯波[1] 刘力 XUE Pengpeng;CAO Fuxiang;DENG Kunkun;NIE Kaibo;LIU Li(College of Materials Science and Engineering,Taiyuan University of Technology,Taiyuan 030024,China;Beijing Composite Materials Co.,Ltd.,Beijing 102100,China;Xingxian Economic Development Zone Aluminum Magnesium New Material Research and Development Company Limited,Lvliang 033603,Shanxi,China)

机构地区：[1]太原理工大学材料科学与工程学院,太原030024 [2]北京玻钢院复合材料有限公司,北京102100 [3]兴县经开区铝镁新材料研发有限公司,山西吕梁033603

出　　处：《航空材料学报》2023年第5期20-28,共9页Journal of Aeronautical Materials

基　　金：国家重点研发计划青年科学家项目(2021YFB3703300);国家自然基金项目(52271109);吕梁市重点研发项目(Rc2020-108)。

摘　　要：采用超声波辅助半固态搅拌铸造工艺制备SiC_(p)/2024Al复合材料,对其进行两步热变形(挤压和轧制),得到厚度为1 mm的SiC_(p)/2024Al复合材料板材,研究SiC_(p)含量对显微组织和力学性能的影响。结果表明:轧制态2024铝合金由带状晶粒和大块CuAl_2相组成;因SiC_(p)对铝基体动态再结晶形核的促进作用,致使2024铝基体晶粒尺寸显著细化;随着SiC_(p)体积分数的增加,其宏观分布更加均匀;两步变形导致SiC_(p)与CuAl_2相的破碎,破碎程度随SiC_(p)体积分数增大而增大,当SiC_(p)体积分数为15%时,SiC_(p)尺寸降至约4.9μm;随SiC_(p)体积分数的增加,屈服强度逐渐增大,当SiC_(p)体积分数为10%时,SiC_(p)/2024Al复合材料的综合力学性能最为优异,其屈服强度、极限抗拉强度和断后伸长率分别达到305、490 MPa和8%;随着SiC_(p)体积分数的增加,SiC_(p)/2024Al复合材料的热膨胀系数降低,弹性模量提高,当SiC_(p)体积分数为15%时,弹性模量可达96 GPa,相较于2024铝合金,提高了37.1%。SiC_(p)/2024Al composite material was prepared by ultrasonic assisted semi-solid stirring casting process,and then the two-step hot deformation(extrusion and rolling)was carried out to obtain SiC_(p)/2024Al composite sheet with a thickness of 1 mm,the influence of SiC_(p) content on its microstructure and mechanical properties was investigated.The results show that the rolled 2024 aluminum alloy consists of banded grains and bulk CuAl2 phase.Due to the promotion effect of SiC_(p) on the dynamic recrystallization nucleus of the Al matrix,the grain size of the 2024 aluminum matrix was significantly refined.With the increase of the volume fraction of SiC_(p),its macroscopic distribution becomes more uniform.The two-step deformation results in the fracture of SiC_(p) and CuAl2 phases,the fracture degree increases with the increase of the volume fraction of SiC_(p).When the SiC_(p) volume fraction is 15%,the SiC_(p) size is reduced to about 4.9μm.With the increase of the SiC_(p) volume fraction,the yield strength gradually increases.When SiC_(p) volume fraction is 10%,the comprehensive mechanical properties of SiC_(p)/2024Al composite plate are the best,and its yield strength,ultimate tensile strength and elongation can reach 305,490 MPa and 8%respectively.With the increase of SiC_(p) volume fraction,the thermal expansion coefficient of SiC_(p)/2024Al composite decreases and the elastic modulus increases,when the SiC_(p) volume fraction is 15%,the elastic modulus can reach 96 GPa,which is 37.1%higher than the 2024 aluminum alloy.

关 键 词：金属基复合材料 SiC_(p) 热变形 弹性模量 力学性能 

分 类 号：TB331[一般工业技术—材料科学与工程]