钢板热浸镀铝锌合金镀层的形成过程及其结构分析

The Forming Process and Structure Analysis of the Coating During Hot Dipping 55% Al-Zn Alloy on the Sheet Steel

分析了Q2 35冷轧钢板在 62 0℃下浸镀 5 5 %铝锌合金时镀层的形成过程和机理 ,测定了金属间化合物层的孕育期长大动力学曲线。认为镀层的化合物层最初形成的是Fe Al Si三元化合物 ,且需要 4～ 5s的孕育期。浸镀时间较长时 ,化合物则主要由Fe2 Al5和FeAl3所组成。合金层的外层来自镀浴表层 ,内层来自浸镀过程中所形成的边界层。

The mechanism and the kinetics of intermetallic compounds formed during hot-dipping 55%Al-Zn alloy, at the usually temperature 620 ℃, had been analysed. The author think that the compounds formed originally was Fe-Al-Si ternary compounds, and 4 to 5 seconds pregnant periods was needed. After longer time hot-dipping, the compounds were consist of Fe 2Al 5 and FeAl 3 mainly. Consist of two layer: the outside layer come from the surface of the bath, the inside layer come from the boundary layer, The alloy layer of the inside layer could form parts of intermetallic compounds during crystallizing.