TCB_(p)及AlN_(p)对Al-9Si-3Cu合金导热及力学性能的影响

Effect of TCB_(p) and AlN_(p) on Heat Conduction and Mechanical Properties of Al-9Si-3Cu Aluminum Alloy

采用B掺杂型TiC粒子(TCB_(p))及纳米AlN粒子(AlN_(p))对Al-9Si-3Cu合金进行晶粒细化及强化处理,通过光学显微镜、场发射扫描电镜、万能试验机、激光导热测试仪等对Al-9Si-3Cu合金的微观组织、力学及导热性能进行测试和分析。结果表明:以晶种合金形式添加TCB_(p)及纳米AlN_(p)后,Al-9Si-3Cu合金的α-Al晶粒明显细化,AlN_(p)分布于合金共晶区;铸态合金的抗拉强度和伸长率由209 MPa和4.5%提高至228 MPa和7.3%,分别提高了9.1%和62.2%。经180℃时效6 h后,抗拉强度及伸长率进一步提升至239 MPa和9.6%;添加晶种合金并经时效处理后,Al-9Si-3Cu合金的热导率由197.2 W/(m·K)提升至198.2 W/(m·K)。基于TCB_(p)及纳米AlN_(p)的协同作用制备了一种高导热高强韧Al-9Si-3Cu合金。

The Al-9Si-3Cu alloy was refined and strengthened by B doped TiC particles(TCB_(p))and nano AlN particles(AlN_(p)).The microstructure and properties were evaluated through optical microscope,field emission scanning electron microscopy,universal testing machine and laser thermal conductivities testing instrument.The results showed thatα-Al grains were obviously refined and the AlN_(p)particles were distributed in eutectic region.The tensile strength and elongation increased from 209 MPa and 4.5%to 228 MPa and 7.3%,which increased by 9.1%and 62.2%,respectively.After aging at 180℃for 6 h,the tensile strength was further increased to 239 MPa and the elongation was increased to 9.6%.After adding both of the master alloys and aging treatment,the thermal conductivities of the Al-9Si-3Cu alloy was also optimized from 197.2 W/(m·K)to 198.2 W/(m·K).Therefore,the improved Al-9Si-3Cu alloy with higher thermal conductivities and mechanical properties was prepared.