Effect of Zn-Coating Process on Liquid Metal Embrittlement of TRIP Steel

The study investigated the microstructural evolution of the coating and liquid metal embrittlement (LME) sensitivity of the transformation induced plasticity (TRIP) steel sheets which were prepared by different coating processes: (i) continuous galvanizing, (ii) galvannealing, or (iii) electro-galvanizing. Hot tensile testing and microstructural analyses showed that the coating process influenced Fe-Zn reaction which controlled the contact between steel substrate and liquid Zn alloy at the high temperature. Because Fe-Zn reaction was the fastest in the electro-galvanized TRIP steel, it exhibited the highest resistance to LME, while the continuously galvanized steel resulted in the highest susceptibility to LME.

Automated summary

This study investigated the microstructural evolution of TRIP steel sheets prepared by different coating processes and their sensitivity to liquid metal embrittlement (LME). The results showed that the coating process influenced the Fe-Zn reaction, which controlled the contact between the steel substrate and liquid Zn alloy at high temperatures. The electro-galvanized TRIP steel exhibited the highest resistance to LME, while the continuously galvanized steel was the most susceptible.