Sn and Al whiskers growth on Cr-Al-B MAB phase formed during interfacial reaction between Fe-Cr-B cast steel and molten Al-Sn-Si alloy

New discovery in whisker growth on Cr-Al-B MAB phase, which was formed during hot-dip aluminizing and subsequent thermal diffusion treatment of Fe-Cr-B cast steel, after cultivation under 400 °C, was found. Specifically, along with the growth of Sn whiskers on the whitened Cr-Al-B MAB phase, Al whiskers also formed, mainly attributed to the thermal activation of whisker cultivation at 400 °C and promotion effect of Sn in the Cr-(Al, Sn)-B MAB phase solid solution. Partial Al whiskers, interspersed with small amounts of Sn, exhibited transparency under the scanning electron microscopy image. These whiskers underwent random growth and sucking back into the matrix simultaneously. The temperature during whisker cultivation had a significant effect on the whisker growth.