摘要
分别制备了未添加和同时添加0.1%(质量分数,下同)锆和0.2%镧的铸态Al-Zn-MgCu合金,然后进行了均匀化、固溶和时效处理,研究了锆、镧的添加对该合金显微组织和力学性能的影响。结果表明:添加0.1%锆和0.2%镧后,该合金的形核率增加,组织分布更加均匀,晶粒得到了细化;其铸态硬度、抗拉强度、伸长率分别比未添加锆、镧的提高了13.60%,25.00%,21.88%;断裂方式由未添加锆、镧合金的沿晶断裂转变为韧窝型穿晶断裂,合金的韧性得到了提高。
Al-Zn-Mg-Cu alloys without and with the addition of 0.1wt% Zr and 0.2wt% La were prepared, respectively, and then were subjected to homogenizing, solution, and aging treatment. The effects of Zr and La addition on the microstructure and mechanical properties of Al-Zn-Mg-Cu alloys were investigated. The results show that with the addition of 0.1wt% Zr and 0.2wt% La, the nucleation rate of the alloy increased, the microstructure distribution was more uniform and the grains were refined; the as-cast hardness, tensile strength and elongation increased by 13.60%, 25.00%, 21.88% comparing to those of without Zr and La; the fracture mode changed from the intergranular fracture of the alloy without Zr and La to the dimple transgranular fracture, indicating the improvement of the alloy toughness.
出处
《机械工程材料》
CAS
CSCD
北大核心
2017年第2期102-105,共4页
Materials For Mechanical Engineering
基金
国家自然科学基金资助项目(51561029)
