热冲压工况下GA镀层组织演变及粉化现象  

Microstructure evolution and pulverization phenomenon of GA coating under hot stamping conditions

作　　者：陈炜[1] 黎小洲 曹一枢 白瑛 张小计 陈春刚 CHEN Wei;LI Xiao-zhou;CAO Yi-shu;BAI Ying;ZHANG Xiao-ji;CHEN Chun-gang(School of Mechanical Engineering,Jiangsu University,Zhenjiang 212013,China;Wuxi Shuguang Precision Industry Co.,Ltd.,Wuxi 214145,China)

机构地区：[1]江苏大学机械工程学院,江苏镇江212013 [2]无锡曙光精密工业有限公司,江苏无锡214145

出　　处：《塑性工程学报》2025年第3期46-52,共7页Journal of Plasticity Engineering

基　　金：国家自然科学基金资助项目(51875263);无锡市“太湖之光”科技攻关(产业化关键技术攻关)项目(WX0304B010301220019PD)。

摘　　要：利用扫描电镜并结合元素能谱分析仪研究了热镀锌合金化超高强钢板在热冲压工况下镀层组织的演变过程,并对镀层粉化、剥落等损伤机理进行了讨论。结果表明:加热温度为600~680℃时,镀层的主要组织由δ_(1k)相组成,温度升高至720℃后,δ_(1k)相向Г相与液Zn转变,镀层中氧含量增加。当温度升高至810℃时,Г相与氧化物ZnO的含量达到顶峰,温度达到奥氏体温度870℃以上时,α-Fe(Zn)相成为主体,此时只有表面氧化物ZnO与少量的Г相存在。在成形前GA镀层内部存在预裂纹,由于液Zn的液态金属致脆导致裂纹的进一步扩展,随着淬火与成形的开展,在压应力的作用下使得镀层内部的裂纹沿横向扩展,造成了粉化以及剥落现象。The evolution process of the coating structure of hot-dip galvanized alloyed ultra-high strength steel plate under hot stamping conditions was studied using scanning electron microscopy(SEM)and energy disperse spectroscopy(EDS),and the damage mechanisms such as coating pulverization and peeling were discussed.The results indicate that when the heating temperature is 600-680℃,the main structure of the coating is composed of δ_(1k) phases,when the temperature rises to 720℃,δ_(1k) phases transform intoГPhase and liquid Zn,and the oxygen content in the coating increases.When the temperature rises to 810℃,the content of theГphase and oxide ZnO reach the peak and when the temperature reaches above 870℃for austenite,the α-Fe(Zn)phase becomes the main body,at this time only the surface oxide ZnO and a small amount ofГphases exist.Before forming,there are precracks inside the GA coating.Due to the embrittlement caused by the liquid metal of liquid Zn,the cracks further expand.As quenching and forming progress,under the action of compressive stress,the cracks inside the coating expand laterally,causing pulverization and peeling phenomena.

关 键 词：GA镀层 热冲压 镀层组织演变 镀层粉化 损伤分析 

分 类 号：TG156.1[金属学及工艺—热处理]