A Study on the Formation of Partially-Melted Regions in Weld Heat-Affected Zone of High Strength Steel (Part 1)
Observation of Partially Melted Regions and Segregation in Bands
1979 Volume 48 Issue 12 Pages 1070-1077
Details
1979 Volume 48 Issue 12 Pages 1070-1077
It seems very likely that cold cracking due to hydrogen can be nucleated from either liquated grain boundaries and/or liquated segregation bands in weld heat-affected zone. It has been in need to make much study on the formation of partially-melted regions in HAZ of steel weldment.
In this study, the effect of alloying elements and carbon content on partially melting in HAZ of several steels made in a laboratory was examined using a high temperature microscope.
Preferential grain-boundary liquation, which occurred at the lower temperature than the solidus, was observed at synthetic HAZ of steels with carbon contents above 0.1 wt%, and was the most remarkable at about 0.14 wt% carbon content.
It was known that there was a close correlation between the liquation phenomenon of grain boundary and the segregation tendency of alloying elements (Ni, Cr and Mo) at the bands associated with worked cast ingot.
