Liquation cracking susceptibility of remelted and reheated weld metals in CM247LC superalloy using multi-bead Varestraint testing

Abstract

The liquation cracking temperature range (LCTR) of CM247LC was evaluated, especially in remelted and reheated weld metals produced during multi-pass repair welding. The LCTR of the remelted weld metal was 282 K, and those of the reheated weld metals were 455–805 K depending on the testing position. In the multi-bead within the reheated weld metal, the LCTR increased from 455 K far from the inter-pass boundary to 805 K near this boundary. The mechanism underlying the varying LCTR for the remelted and reheated weld metals was the amount of MC carbide at each weld position. The single-mode fibre laser welding suppressed the carbide within both areas, and lowered the liquation cracking susceptibility.

KEYWORDS:

• CM247LC superalloy
• repair welding
• heat-affected zone
• microstructure
• carbide
• liquation cracking susceptibility
• Varestraint test
• single-mode fibre laser welding

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by Ministry of Trade, Industry and Energy [grant number 20011103, 20015063].