Cu含量对Al-12Si合金组织结构及导热性能的影响  

Effects of Cu Content on Microstructure and Thermal Conductivity of Al-12Si Alloy

作　　者：沈晓东 翁文凭 杨蕾 范卫忠 长海博文 陈小村 Sheng Xiaodong;Weng Wenping;Yang Lei;Fan Weizhong;Hiromi Nagaumi;Chen Xiaocun(School of Iron and Steel,Soochow University;Guangdong Hongbang Metal Aluminum Co.,Ltd.)

机构地区：[1]苏州大学沙钢钢铁学院 [2]广东鸿邦金属铝业有限公司

出　　处：《特种铸造及有色合金》2019年第1期87-90,共4页Special Casting & Nonferrous Alloys

基　　金：江苏省自然科学基金资助项目(BK20151221)

摘　　要：采用熔铸工艺制备了不同Cu含量(0.03%～4.2%)的Al-12Si-xCu-0.6Mg合金试样,分析Cu含量对Al-Si合金组织结构、力学性能与导热性能的影响。结果表明,随着Cu含量从0.03%增加到4.2%,Al-12Si-xCu-0.6Mg合金强度由212.3 MPa提高到285.3MPa,但热导率由152W/(m·K)降低到119W/(m·K)。另外,随着Cu含量增加,合金中初生α-Al相明显细化,从发达树枝晶向细小圆整等轴晶转化,共晶Si相晶粒尺寸逐渐增大;分散的块状α-Al相会造成电子传导通道的断裂,粗大的共晶Si提高电子运动过程中的散射概率,降低自由电子的平均自由程,从而导致合金导热性能下降。The Al-12 Si alloys with different Cu contents were prepared by metal mold casting.The effects of Cu on the mechanical properties and thermal conductivity of Al-12Si-xCu-0.6Mg alloys were investigated.The results reveal that the mechanical properties are enhanced greatly as the Cu content increase.With the increase of Cu content,the strength of Al-12Si-xCu-0.6Mg alloy is increased from 212.3MPa to 285.3MPa,while the thermal conductivity is decreased from 152W/(m·K)to 119W/(m·K).Microscopic analysis reveals that with the Cu content increase,α-Al is refined gradually from the developed dendrite to fine equiaxed grain and eutectic Si phase is coarsened.The dispersed blockα-Al cause the fracture of the electronic thermal conduction channel of the alloy,and the coarse eutectic Si can increase the scattering of electron conduction,resulting in a decrease of the thermal conductivity of the alloy.

关 键 词：AL-SI合金 微观组织 热导率 力学性能 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG113.223[金属学及工艺—金属材料]