Precipitation of σ Phase Using General Diffusion Equation with Comparison to Vitek Diffusion Model in Dissimilar Stainless Steels

Abstract EN

This study performs a precipitation examination of the σ phase using the general diffusion equation with comparison to the Vitek model in dissimilar stainless steels during multipass welding.

Experimental results demonstrate that the diffusivities (DCrδ, DNiδ, and DSiδ) of Cr, Ni, and Si are higher in δ-ferrite than (DCrγ, DNiγ, and DSiγ) in the γ phase, and that they facilitate the precipitation of the σ phase in the third pass fusion zone.

The Vitek diffusion equation can be modified as follows: (Diffusivity)General=Modified Constant×(Diffusivity)Vitek.