钨极氩弧焊焊接参数对M951高温合金的焊接热裂纹影响机制研究OA

The application of Tungsten Inert Gas(TIG)welding technology for repairing aero-engine hot-section compo-nents made of nickel-based superalloy M951 offers significant advantages in reducing maintenance costs and extending ser-vice life.This study systematically investigates the influence of arc welding parameters and filler materials on the hot crack-ing susceptibility of M951 superalloy,with particular focus on the crack initiation locations and underlying mechanisms un-der various welding conditions.Experimental results demonstrate that weld joints deposited with M951 filler wire exhibit markedly lower cracking susceptibility compared to those fabricated using GH4169 filler wire.The total crack length and number of cracks within the joint initially increase and then decrease with rising welding current.At lower current levels,cracks primarily propagate along the weld centerline,presenting as solidification cracks along interdendritic boundaries in the fusion zone.In contrast,higher welding currents promote the formation of liquation cracks within the heat-affected zone(HAZ).The minimum susceptibility to hot cracking was achieved at a welding current of 40 A.