摘要
采用剪切低温浇注式(LSPSF)半固态浆料制备工艺制备7075铝合金铸棒,并依次进行均匀化处理、热挤压和T6热处理,研究了热挤压和热处理对铝合金显微组织和拉伸性能的影响。结果表明:铸态铝合金中的近球形晶粒在热挤压过程中变为不规则形状,经T6热处理后,铝合金组织中出现较明显的晶界;热挤压和T6热处理使铝合金组织中的(110)晶面产生择优取向;经热挤压后,铝合金的抗拉强度和屈服强度比铸态的分别提高了136%和140%,经T6热处理后,抗拉强度和屈服强度进一步提高;铸态铝合金的断裂方式为脆性断裂,经热挤压和T6热处理后,其断裂方式均为韧性断裂。
7075 aluminum alloy casting rod was prepared by using semi-solid slurry preparation process of low superheat pouring with a shear field（LSPSF）,and homogenization treatment,hot extrusion and T6 heat treatment were carried out in sequence.The effect of hot extrusion and heat treatment on microstructure and tensile properties of the aluminum alloy was investigated.The results show that the near spherical grains in the as-cast aluminum alloy changed into irregular shapes in the process of hot extrusion.The relatively obvious grain boundary in the structure of the aluminum alloy was formed after T6 treatment.（110）crystal plane in the microstructure of the aluminum alloy had preferred orientation after treated by hot extrusion and T6 heat treatment.The tensile strength and yield strength of the aluminum alloy treated by hot extrusion increased by 136% and 140% comparing with those of the aluminum alloy in as-cast state,respectively.After T6 heat treatment,the tensile strength and yield strength were further improved.The fracture mode of the aluminum alloy in as-cast state was brittle fracture,and the fracture modes after hot extrusion and T6 heat treatment were both ductile fracture.
出处
《机械工程材料》
CAS
CSCD
北大核心
2018年第1期39-43,共5页
Materials For Mechanical Engineering
基金
国家自然科学基金资助项目(11364031)
江西省科技厅重点项目(20161ACE50021)
关键词
半固态方法
7075铝合金
热挤压
热处理
拉伸性能
semi-solid method
7075 aluminum alloy
hot extrusion
heat treatment
tensile property
作者简介
朱永博（1993-），男，甘肃定西人，硕士研究生;通信作者（导师）：杨湘杰教授
