摘要
通过力学性能检测、DSC热分析、金相显微镜和扫描电镜观察研究了经过双级均匀化和强热变形工艺的2D70铝合金挤压棒材固溶处理温度和时间对合金组织与电导率的影响。结果表明,合金经过固溶处理后可溶第二相已基本溶入基体中,残余的高熔点难溶相主要为近球形白色高亮度Al7Cu4Ni相和灰色块条状、棒状或球状Al9FeNi相;随着固溶温度升高,材料强度、硬度和伸长率都呈上升趋势,电导率则呈下降趋势,但性能曲线随固溶温度变化相对平缓,合金较为理想的固溶处理温度为535~545℃。随着固溶时间的延长,显微组织变化不明显,强度呈上升趋势,固溶120 min时强度和硬度都达到峰值,分别是440 MPa和140 HB,此时伸长率为12%,随固溶时间延长电导率总体变化不大。
The effect of solid solution treatment temperature and time on the microstructure and electrical conductivity of 2D70 aluminum alloy extrusion rod after two-stage homogenization treatment and extensive deformation process was studied by means of mechanical property test,optical microscope,scanning electron microscope observation and electrical conductivity test.The results show that after solution treatment,the soluble phases dissolve completely in matrix.Insoluble remainder phases with high melting temperature are mainly white spherical Al7Cu4Ni phase with high brightness and gray Al9FeNi phase in the shape of block strip,rod-like or globular.With increasing the solution treatment temperature,yield strength,tensile strength and hardness increases,and the electrical conductivity decreases.However,the mechanical property and electricity conductivity curves are relatively flat with the variation of the solution treatment temperature.The optimal solution temperature of the alloy is 535-545 ℃.With increasing the solution time,the microstructure of the alloy does not change significantly,but the strength increases.The strength and hardness reaches a peak when the solution treatment time is 120 min,which is 440 MPa and 140 HB,respectively.Also,the elongation reaches 12%when the solution time is 120 min.The conductivity has little change with increasing the solution time.
出处
《金属热处理》
CAS
CSCD
北大核心
2010年第3期37-42,共6页
Heat Treatment of Metals
基金
国家十一五科技支撑课题(2007BAE38B06)
关键词
2D70铝合金
显微组织
固溶处理
力学性能
2D70 aluminum alloy
microstructure
solution treatment
mechanical property
