基板晶体学特征对镀层相结构及抗粉化性能的影响

为了改善合金化镀锌板镀层的抗粉化性能，研究了基板晶体学特征对合金化镀层相结构及抗粉化性能的影响.结果表明:γ 织构增加基板成型性的同时抑制镀层内裂纹源的萌生;板面织构(111)-(113)-(313)//RP (轧面)在镀锌过程中，抑制ζ相的生成，促进δ相的生成;板面织构(001)-(101) //RP促进ζ相的生成.在合金化退火过程中镀锌板ζ相转变为δ相，最后变为Γ相，导致镀层内产生不同相结构，进而影响镀层的抗粉化性能和与基板之间的黏附力.此外，增加基板上113〈110〉体积分数与111〈110〉体积分数的比值，更有利于镀层内非基面织构的生成，增加合金化镀层的塑性.另外，基板表面的大、小角度晶界的体积分数也是影响镀层相结构的主要因素.

Effect of Substrate Steel Crystallographic Features on Coating Phase Structure and Powdering Resistance

In order to improve the powdering resistance of galvannealed coating， the effects of substrate steel crystallographic features on the galvannealed (GA) coating phase structure and powdering behavior were studied. The results show that γ texture can improve the formability of substrate and retrain the crack propagation of coating. The presence of (111)-(113)-(313)//RP at the top of the substrate promotes the formation of δ phase. However， ζ phase with high growth rate are formed on (001)-(101)//RP of substrate steel. ζ phase is transformed into δ phase and finally transformed into Γ phase during the galvannealed processes and led to different phase structures， thus affecting powdering properties and adhesive between coating and substrate. Additionally， both the ratio of volume fraction of 113〈110〉to that of 111〈110〉， and the fraction of high (low) energy boundaries play a vital role in the formation and growth of Fe-Zn intermetallic phase.