ZL702A铝合金双硬度峰值时效行为与微观组织分析  

Analysis of Double-hardness-peak Aging Behaviors and Microstructure of ZL702A Aluminum Alloy

作　　者：肖璐 蒲博闻 宋跃文 杨晨帆 王韬 周海涛 XIAO Lu;PU Bowen;SONG Yuewen;YANG Chenfan;WANG Tao;ZHOU Haitao(School of Materials Science and Engineering,North University of China,Taiyuan 030051,China;China North Engine Research Institute(Tianjin),Tianjin 300400,China;Taiyuan Heavy Machinery Group Co.,Ltd.,Taiyuan 030024,China)

机构地区：[1]中北大学材料科学与工程学院,山西太原030051 [2]中国北方发动机研究所(天津),天津300400 [3]太原重型机械集团有限公司,山西太原030024

出　　处：《热加工工艺》2024年第16期30-34,共5页Hot Working Technology

基　　金：山西省基础研究计划面上项目(202103021224179)。

摘　　要：将经490℃×4 h+500℃×6 h+520℃×8 h固溶、室温水介质淬火后的ZL702A铝合金在160、170℃两个温度下进行不同时间的时效处理,结合显微硬度法和透射电镜显微组织分析,研究ZL702A铝合金时效硬化行为与析出相演化规律之间的关联性。结果表明,ZL702A在160和170℃时效温度下的时效硬化曲线均表现出双硬度峰值的时效行为。这种时效强化现象归因于合金GP区向θ"、θ'、θ相的转变和Q'相粗化的共同作用。在160℃时效12 h对应的第一硬度峰值期,合金的硬度为114 HV,此时析出相对位错运动产生最大的阻碍作用,合金得到最理想的时效强化效果。ZL702A aluminum alloy after 490℃×4 h+500℃×6 h+520℃×8 h solution and quenching in the water medium at room temperature was aged at 160℃and 170℃for different time.The relationship between aging hardening behavior and precipitate transformation of ZL702A was studied by microhardness method and transmission electron microscopy(TEM).The results show that the aging hardening curves of ZL702A at both 160℃and 170℃exhibit double-hardness-peak aging behavior.The aging strengthening phenomenon is attributed to the combination of transformation of the GP zone toθ",θ',θphases with coarsening of Q'phase.In the first hardness peak period corresponding to aging at 160℃for 12 h,the hardness of the alloy is 114 HV.At this time,the dislocation movement is severely hindered and the alloy obtains the most ideal aging strengthening effect.

关 键 词：时效强化 ZL702A铝合金 析出序列 双硬度峰 

分 类 号：TG156.92[金属学及工艺—热处理]