Microstructure-based modeling of hydrogen assisted cracking in pearlitic steels

This paper analyzes the process of hydrogen assisted cracking in pearlitic steels, which are increasingly cold drawn in the course of manufacturing to produce prestressing steel wires used in prestressed concrete. A microstructure-based modeling of the environmentally-assisted fracture phenomenon is proposed to rationalize the results for diferent degrees of drawing. The approach is based on two items — (i) the model by Miller and Smith of shear cracking (SC) in pearlite; (ii) the mechanism of hydrogen enhanced decohesion (HEDE) proposed by Gerberich. There is an evolution from a predominant micromechanism of SC in slightly drawn steels to a predominant micromechanism of HEDE in heavily drawn steels.