合金化参数对烘烤硬化钢表面热镀锌合金化镀层结构和抗粉化性能的影响

摘要

在不同合金化温度和时间下在H220BD烘烤硬化钢表面制备了热镀锌合金化镀层,研究了镀层的形貌、化学成分与抗粉化性能.结果表明:随着合金化温度的升高、合金化时间的延长,镀层与钢基体之间的锌铁互扩散变充分,铁锌合金相逐渐生成且向镀层表面生长,其形态由条柱状逐渐转变为细小颗粒状,镀层的平均铁含量与粉化量增加;当合金化温度为480℃、合金化时间为25 s时,镀层性能较佳,铁锌合金相呈细小颗粒状,镀层粉化量较小.%Hot galvannealing coating on surface of H220BD bake-hardening steel was prepared at different galvannealing temperatures for different times.The morphology,chemical composition and powdering resistance of the coating were studied.The results show that with the increase of galvannealing temperature or the extension of galvannealing time,the zinc and iron in the coating and steel substrate diffused fully,the iron-zinc alloy phase was formed and extended to the surface of the coating with the shape from strip columnar to fine granular,and the average iron content and powdering mass of the coating increased.When the galvannealing temperature was 480 ℃and the galvannealing time was 25 s,the performance of the coating was relatively good;the iron-zinc alloy phase was in a finer-grained shape and the powdering mass of the coating was relatively small.