Progress of Hot Cracking of Weld Metal and Strength &Toughness of Weld Joint for Nickel-based Alloy

The progress of the hot cracking of weld metal and strength & toughness of weld joint for nickel-based alloy was reviewed in this paper. It concludes that 1) the susceptibility of ductility-dip cracking to weld metal can be decreased by adding Nb,Al,Ti and Ce alloying elements in filler wire.The formation of S,P,Si,Bi low melting point compounds can be prevented by adding Mn and Mg.Besides,the cracking resistance of weld metal can be improved by controlling the ratio of TiO₂,SiO₂,ZrO₂ and MnO₂ slagging agents in the flux; 2) by adopting appropriate welding process,the hot cracking of weld metal can be effectively avoided. The influence of new welding process,such as laser beam welding and electron beam welding,to the hot cracking of weld metal will be the hit issue of future study;3) using the post weld heat treatment of solid solution and double aging,the strength and toughness of weld joint can be improved significantly. The tensile strength of weld joint can be improved by adding Al,Ti,Nb,Mo and Mn in filler. However,the impact toughness of weld joint will be decreased with the mass fraction of Mn increased in the filler wire.