挤压态7B04铝合金的均匀化退火工艺优化  

Homogenization Annealing Process Optimization of Extruded 7B04 Aluminum Alloy

作　　者：周晓平 田壮壮 刘玉芬 ZHOU Xiaoping;TIAN Zhuangzhuang;LIU Yufen(College of Telecommunications and Intelligent Manufacturing,Zhengzhou Sias University,Zhengzhou 450000,China;School of Mechanical and Electrical Engineering,Henan University of Science and Technology,Luoyang 471000,China)

机构地区：[1]郑州西亚斯学院电信与智能制造学院,郑州450000 [2]河南科技大学机电工程学院,洛阳471000

出　　处：《机械工程材料》2025年第2期48-54,共7页Materials For Mechanical Engineering

基　　金：河南省科技攻关计划项目(222102210282)。

摘　　要：对挤压态7B04铝合金分别进行了单级均匀化退火(退火温度450~490℃,退火时间4~36 h)以及在优化的单级均匀化退火基础上的双级均匀化退火(第二级均匀化退火工艺480℃×4 h/10 h或495℃×4 h/10 h),研究了2种工艺下退火温度和退火时间对合金物相组成、显微组织和硬度等影响,以获得适宜的均匀化退火工艺。结果表明:在单级均匀化退火工艺下,随着退火温度的升高,合金中MgZn_(2)、Al_(2)MgCu等第二相面积分数先减后增,硬度先升后降,而随着退火时间的延长,第二相的面积分数降低,硬度先升后降;单级均匀化退火的优化工艺为退火温度460℃、退火时间24 h,此时大量第二相发生回溶,组织未发生过烧和晶粒长大,合金硬度最高。在双级均匀化退火工艺下,480℃×4 h/10 h第二级均匀化退火后,铝合金中的第二相进一步回溶,组织未发生过烧,且10 h退火时间下的第二相面积分数更低,合金硬度更高;当第二级均匀化退火温度升高至495℃时,铝合金发生过烧。挤压态7B04铝合金适宜的双级均匀化退火工艺为460℃×24 h+480℃×10 h,此时合金中第二相已基本回溶,仅存在少量尺寸约为1μm的类球形Al_(2)MgCu相。The extruded 7B04 aluminum alloy was subjected to single stage homogenization annealing(annealing temperature of 450‒490℃,annealing time of 4‒36 h)and double stage homogenization annealing(the second stage homogenization annealing process of 480℃×4 h/10 h or 495℃×4 h/10 h)based on the optimized single stage homogenization annealing.The effects of annealing temperature and time of the two processes on the phase composition,microstructure,and hardness of the alloy were studied.The optimal homogenization annealing process was obtained.The results show that after the single stage homogenization annealing with the increase of annealing temperature,the area fraction of the second phase,such as MgZn_(2) and Al_(2)MgCu,first decreased and then increased,and the hardness first increased and then decreased;with the extension of annealing time,the area fraction of the second phase decreased,and the hardness first increased and then decreased.The optimal process of single stage homogenization annealing was annealing temperature of 460℃and annealing time of 24 h,and at this time a large number of the second phase was redissolved,and no overburning and grain growth occurred in the structure,and the hardness of the alloy was the highest.Under the double stage homogenization annealing process,after the second stage homogenization annealing of 480℃×4 h/10 h,the second phase of the aluminum alloy was further redissolved,and the microstructure did not overburn;the area fraction of the second phase under the annealing time of 10 h was lower,and the hardness of the alloy was higher.When the second stage homogenization annealing temperature increased to 495℃,overburning of the aluminum alloy occurred.The optimal double stage homogenization annealing process for the extruded 7B04 aluminum alloy was 460℃×24 h+480℃×10 h.At this time,the second phase was basically dissolved,and only a small amount of spherical-like Al_(2)MgCu phase with size about 1μm existed.

关 键 词：7B04铝合金 单级均匀化退火 双级均匀化退火 显微组织 第二相 

分 类 号：TG146.2[一般工业技术—材料科学与工程]