摘要
通过金相显微镜(OM)、扫描电镜(SEM)、透射电镜(TEM)观察和硬度、抗拉强度检测等手段,研究了复合添加质量分数为0.22%的Sc+0.15%的Zr和0.22%的Sc+0.15%的Zr+0.53%的Hf两种组合对新型AlMg7Si3铝合金微观组织与力学性能的影响。结果表明,两种复合微合金化均能明显细化铸态晶粒,形成细小的球状晶体。复合添加Sc、Zr、Hf在铝基体中形成了纳米级的矩形析出相,晶粒细化更明显。复合微合金化的强化机制为细晶强化和弥散强化,AlMg7Si3合金添加0.22%的Sc、0.15%的Zr和0.53%的Hf并经时效热处理后,合金的硬度(HBW)提高到了110,室温抗拉强度提高到294MPa,350℃高温抗拉强度提高到99MPa。
Effects of the combination of 0.22%Sc+0.15%Zr and 0.22%Sc+0.15%Zr+0.53%Hf on the microstructure and mechanical properties of novel AlMg7Si3casting aluminum alloy were investigated by means of optical microscope(OM),scanning electron microscopy(SEM),transmission electron microscopy(TEM)as well as hardness and tensile strength testing.The results indicate that both compound microalloying can obviously refine as-cast grains,forming fine spherical crystals,and that with composite addition of Sc,Zr and Hf is refined more significantly.The elements Sc,Zr and Hf are formed into nano-sized rectangular precipitates in the aluminum matrix.The strengthening mechanism of Sc,Zr and Hf composite microalloying is characterized by fine grain strengthening and diffusion strengthening.After adding 0.22%Sc,0.15%Zr and 0.53%Hf and aging heat treatment,the hardness(HBW)of AlMg7Si3alloy is increased to 110,and the room temperature tensile strength is increased to 294MPa,which is then increased to 99MPa at 350℃.
作者
朱鸿磊
陈大辉
刘永强
刘辰
徐英
洪晓露
张将
彭银江
Zhu Honglei;Chen Dahui;Liu Yongqiang;Liu Chen;Xu Ying;Hong Xiaolu;Zhang Jiang;Peng Yinjiang(Ningbo Branch,China Ordnance Science Research Institute)
出处
《特种铸造及有色合金》
CAS
北大核心
2022年第9期1181-1184,共4页
Special Casting & Nonferrous Alloys
基金
宁波市2025重大专项资助项目(2019B10099)
