材料期刊网

铝锌硅镀层(Galvalume)作为钢铁基体的热浸镀材料,具有良好的耐腐蚀能力,但是Galvalume镀层在受力变形时容易出现裂纹.针对热浸镀Galvalume镀层成形开裂问题,通过对不同镀层厚度(重量)镀铝锌板进行冲压试验和180°弯曲试验,观察裂纹源的产生.采用扫描电镜(SEM)和能谱(EDS)对镀层及中间过渡层进行研究,分析影响镀层冲压开裂的原因.结果显示:镀层的重量(厚度)是影响其冲压开裂的主要原因,随着镀层厚度的下降,镀层外侧受拉应力作用开裂趋势变小;开裂位置显示主要元素为Fe、AI、Si元素,变形过程中Galvalume合金过渡层相对于镀层更容易开裂;Galvalume合金过渡层的厚度是影响Galvalume冲压开裂的主要原因,随着合金过渡层厚度的降低,过渡层开裂趋势变小.

In this paper,the reason of the coating crack source was studied by using stamping test and 180° bending test for different coating thickness (weight)of hot-dipping galvalume steel sheet,and the formation of crack source was observed.The hot-dipping galvalume coating and transition layers were tested by scanning electron microscope (SEM) and energy diffusion spectroscopy (EDS),and the reason of cracking of coating by stamping was analyzed.Results showed that the coating thickness (weight) was the main reason of cracking,and with the increase of coating thickness,the cracking trend of coating on the lateral part decreased.In the crack position,Fe,Al and Si elements were mainly detected.In the process of deformation,the cracks in transition layer were more easily formed than those in coating.The main reason for leading to the stamping cracking was the thickness of transition layer in Galvalume alloy,and with the decrease of thickness of Galvalume alloy layers,the crack tendency of coating became smaller.