Fe含量对亚共晶Al-Ni合金微观组织、热导率和力学性能的影响  

Effect of Fe Contents on Microstructure,Thermal Conductivity and Mechanical Properties of Hypoeutectic Al-Ni Alloy

作　　者：刘亦贤 刘永昌 万翱翔 王鹏展 Saria Akhtar 葛素静 霍臣明 苑高利 张祎程 熊守美[1,4] LIU Yi-xian;LIU Yong-chang;WAN Ao-xiang;WANG Peng-zhan;SARIA Akhtar;GE Su-jing;HUO Chen-ming;YUAN Gao-li;ZHANG Yi-cheng;XIONG Shou-mei(School of Materials Science,Tsinghua University,Beijing 100084,China;Hebei New Lizhong Nonferrous Metals Group Co.,Ltd.,Baoding 071100,Hebei,China;Hebei Light Metal Alloy Material Technology Innovation Center,Baoding 071100,Hebei,China;Key Laboratory for Advanced Materials Processing Technology,Ministry of Education,Beijing 100084,China)

机构地区：[1]清华大学材料学院,北京100084 [2]河北新立中有色金属集团有限公司,河北保定071100 [3]河北省轻金属合金材料技术创新中心,河北保定071100 [4]先进成形制造教育部重点实验室,北京100084

出　　处：《铸造》2024年第3期282-289,共8页Foundry

基　　金：国家自然科学基金面上项目(52175335)。

摘　　要：研究了不同Fe含量对亚共晶Al-4Ni合金微观组织、热导率以及力学性能的影响。结果表明,当不存在Fe时,合金中的微观组织主要是初生α-Al和(α-Al+Al_(3)Ni)共晶组织。随着Fe元素增加至0.5%,初生相仍为α-Al,共晶组织变为(α-Al+Al_(3)Ni)二元共晶和(α-Al+Al_(3)Ni+Al_(9)NiFe)三元共晶。当Fe含量超过0.75%,初生相为Al_(9)NiFe,同时形成halo铝枝晶,共晶组织变为(α-Al+Al_(9)NiFe)二元共晶和(α-Al+Al_(3)Ni+Al_(9)NiFe)三元共晶。随着Fe元素的加入,Al-4Ni-x Fe合金的热导率呈下降趋势,这主要与合金α-Al基体中Fe原子的固溶量和Al_(9)NiFe相的含量和形貌相关。在力学性能方面,随着Fe的增加,Al-4Ni-x Fe的屈服强度不断增加,伸长率先缓慢下降再急剧下降,这主要是由于合金中形成了Al_(9)NiFe初生相,加速了裂纹的扩展。综合考虑,Al-4Ni-0.5Fe合金的热导率和力学性能取得了较好的权衡,具有最佳的综合性能。Al-Ni alloy is a widely used high-pressure die-cast aluminum alloy system for high thermal conductivity applications,and the influence of Fe content on the thermal conductivity of Al-Ni alloy is very important.In this paper,the effect of different Fe contents on microstructure,thermal conductivity and mechanical properties of hypoeutectic Al-4Ni alloys were studied.The results showed that the microstructure inAl-4Ni alloy was primaryα-Al and (α-Al+Al_(3)Ni) eutectic.As the Fe content increased to 0.5%,the eutectic microstructure became (α-Al+Al_(3)Ni) binary eutectic and (α-Al+Al_(3)Ni+Al_(9)NiFe) ternary eutectic.When the Fe content exceeded 0.75%,the primary Al_(9NiFe) phase and halo aluminum dendrite were formed,and the eutectic microstructure became (α-Al+Al_(9)NiFe) binary eutectic and (α-Al+Al_(3)Ni+Al_(9)NiFe) ternary eutectic.With the addition of Fe,thermal conductivity of Al-4Ni-x Fe alloy declined,which was mainly related to the solubility of iron in theα-Al matrix of the alloy and the content and morphology of the Al9NiFephase.In terms of mechanical properties,with the increase of Fe,yield strength of Al-4Ni-x Fe increased,and the elongation slowly decreased first and then dropped sharply.This was mainly due to the formation of Al9NiFe primary phase in the alloy,which accelerated the crack propagation.Above all,Al-4Ni-0.5Fe alloy with a good trade-off on thermal conductivity and mechanical properties had the best comprehensive property.

关 键 词：AL-NI合金 Fe元素 微观组织 热导率 力学性能 

分 类 号：TG249[金属学及工艺—铸造]