再结晶对钢在铝液中形成的界面相稳定性影响

Effect of Recrystallization of Steel on Stability of Interme-tallic Phases in Molten Al

摘要:

研究了钢的再结晶对热浸铝过程金属间化合物（IMCS）层的稳定性影响，结果表明：304不锈钢在热浸镀过程的再结晶结构重排造成该钢材表面形成了非保护性IMCS层，该合金的腐蚀动力学满足线性规律；再结晶程度较轻的410不锈钢表面形成了稳定且致密的Fe₂Al₅层，该层延缓了其在热浸铝过程的失效。钢材的再结晶对于热浸镀铝过程中界面金属间化合物的影响包括：（1）再结晶可降低IMCS的形核和生长能量，尤其是Fe₄Al₁₃相；（2）再结晶引起的晶粒沿密排方向排布可降低Al离子的扩散速率；（3）再结晶加剧了IMCS/钢界面处的应力失配，尤其是奥氏体钢。

Abstract:

The influence of steel's recrystallization on the stability of intermetallic compounds (IMCS) layer was investigated in molten Al at 700 °C. Results show that high degree of structural rearrangement leads to the formation of non-protective IMCS layer on the 304SS surface and its corrosion kinetics coincides with linear law. Compact and stable Fe₂Al₅ layer delays the failure of the 410SS in liquid Al. The stability of IMCS is affected by steel's recrystallization in three aspects: (1) energy for IMCS nucleation and growth are reduced, especially for Fe₄Al₁₃; (2) grain orientation transforms to close-packed direction which slows down the diffusion rate of Al ion; (3) stress mismatch is increased at the IMCS/steel interface, especially for the austenitic 304SS.