Correlation Between Grain Boundary Character and Grain Boundary Liquation in the Weld Heat-Affected Zone

摘要

Liquation related cracking has been a recurring problem that has hindered joining of single phase heat-resistant alloys for decades. Despite the efforts of numerous researchers, only marginal progress has been made in bridging the understanding between base metal composition and cracking susceptibility. This preliminary study has shown that grain boundary type may play a significant role in the equation to better understand these relationships. Low angle CSL type boundaries appear to be resistant to liquation and subsequent liquation related cracking in the weld HAZ, while high angle random type grain boundaries were more susceptible.