A Study on the Formation of Partially Melted Regions in Weld Heat-Affected Zone of High Strength Steel

概要

論文の詳細を見る
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 teen found necessary to make more basic studies on the formation of partially melted regions in HAZ of steel weldments. In this study, the effects of alloying elements and carbon content on partial melting in HAZ of several steels made in a laboratory were 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 content above 0.1 wt%, and it 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. The change in the segregation ratio of alloying elements in bands under a rapid non-equilibrium heating rate in weld thermal cycle was theoretically analyzed. According to the analysis, alloying elements to cause partial melting, the process and the mechanism of the formation of partially melted regions in HAZ were discussed and proposed.
社団法人溶接学会の論文
1982-04-01