Study Of S,P On The Solidification Cracking Sensitivity For Inconel 690 Welding Wire Deposited Metal

As for the sensitivity of micro-cracks in the deposited metal of Incone1690 nickel-based alloy welding wire for the nuclear main equipment, the influence of trace element on the solidification cracking of 690 welding wire deposited metal was studied in this paper, and in which the detrimental element S+P was the main target. The amount of the solidification cracking was measured by red dot method, and the SEM and auger electron energy spectrum were used to identified the reason of the solidification cracking. Considering the influence coefficient of S,P,Al,Ti,Mn,Si and C, the J criterion that used to evaluating the solidification cracking sensitivity of Incone1690 welding wire was proposed. The expression is:J= 1313.5 (S+P)-3.1Al-0.8Ti-15.0C-1.9Mn-3.6SiThe results showed:S and P were the main elements inducing the solidification cracking for Incone1690 welding wire deposited metal. The solidification cracking may occur when the amount of S+P was low. The sensitivity of solidification cracking increased greatly when the amount of S+P increased. J criterion was the element criterion of solidification cracking sensitivity for Incone1690 welding wire deposited metal, it indicated the value 0.044 which was the critical value that generating solidification cracking for Incone1690 welding wire, and it defined the critical region under different confidence level. The confidence level was 95%: the solidification cracking occurred when J≥1.5; there wasn't solidification when J≤-1.7; the generation probability of solidification cracking was calculated by the expression when-1.7≤J≤1.5.Six welding wires were used to test the validity of J criterion, the validity of J criterion was validated. The welding wires having no solidification cracking HS690 and HS690M were developed based on the J criterion.Zhang Hao Yue (Materials Processing Engineering) Directed by prof. Chen Pei Yin...