Spot weldability of TRIP assisted steels with high carbon and aluminium contents

G. S. Jung, K. Y. Lee, J. B. Lee, H. K. D. H. Bhadeshia and D. W. Suh

Abstract

We examine here the spot welding characteristics of TRIP-assisted steels which contain δ-ferrite as a consequence of their aluminium concentrations of 3.5 or 5.6 wt%, and which also have high carbon contents of 0.3 or 0.4 wt% when compared with conventional automotive steels. The resistance spot welds are tested both in shear and cross tensile tests in order to determine the so-called ductility ratio which is a parameter associated with the fitness of such welds for automotive applications. With an increase of the δ-ferrite fraction from 0.19 to 0.5, the hardness variation across the weld and heat-affected zone is decreased approximately from 400 to 150 HV. It seems that the presence of stable δ-ferrite is helpful in reducing hardness variations, and in achieving a significant ductility ratio of 0.39.

Science and Technology of Welding and Joining, 17 (2012) 92-98.

Download paper

Related papers

martensite-start temperature



Envelope Coefficients Filling welds Hot Delta
Satoh Fields Piping European welds Poles
Mixed Creep Extraordinary ductility Problems Mechanical stabilisation

CML Home Materials Algorithms