含钪Al-Cu合金的显微组织  

Microstructure of Al-Cu alloys containing scandium

作　　者：毛建伟[1] 金头男[1] 徐国富[2] 

机构地区：[1]北京工业大学固体微结构与性能研究所,北京100022 [2]中南大学材料科学与工程学院,长沙100083

出　　处：《中国有色金属学报》2005年第6期923-928,共6页The Chinese Journal of Nonferrous Metals

基　　金：国家重点基础研究发展基金资助项目(G1999064907)

摘　　要：采用硬度测试、金相观察、扫描电镜和透射电镜测试及能谱分析的方法,研究了稀土元素Sc含量对Al4Cu合金组织的影响。结果表明:Sc可显著细化Al Cu合金的网胞组织,减小枝晶间距,细化合金的晶粒组织,提高合金的显微硬度,提高幅度最约70%;将Sc添加到Al4Cu合金中,当w(Sc)≈0.3%时,Sc除部分固溶于基体外,大部分与Al形成Al3Sc相,其与基体的共格或半共格界面促进了θ′(CuAl2)的析出;当w(Sc)>0.3%时,Sc除部分固溶和形成Al3Sc外,还与Al、Cu元素作用形成W(AlCuSc)相,降低Cu在α(Al)中的固溶度,减少Al2Cu(θ′)相的生成,从而降低了合金的性能。The effects of different contents of rare earth Sc on the microstructures of Al-4Cu alloy by means of hardness measurement, optical microscopy(OM), scanning electron microscopy(SEM), transmitting electron microscopy(TEM) and energy spectrum analysis. The results show that the network structures of Al-Cu alloys can be remarkably refined, the distance of dendritic structure decreases, the structure of the alloy can be refined and the micro-hardness can be enhanced 70% or so. With additions of trace Sc to Al-Cu alloy, when the mass fraction of Sc is not more than 0.3%, Sc mostly, besides of a part of Sc existing in α(Al) solid solution, forms Al_3Sc phase with Al. When the amount is up to 0.5%, apart from the above-mentioned, Sc can interact with Al and Cu to form (W(AlCuSc)) phase, resulting in decrement of solid solubility of Cu in α(Al) solid solution and the amount of (CuAl_2(θ′)) phases, reducing the properties of alloy.

关 键 词：稀土 钪 显微组织 AL-CU合金 细化作用 

分 类 号：TG146.2[一般工业技术—材料科学与工程]