WÄRMEREDUZIERTES MAG-SCHWEIßEN DER HEIßRISSEMPFINDLICHEN NI-BASISLEGIERUNG ALLOY 625 (2.4856)

Анотація

Modified short arc GMA welding techniques for thin sheet applications provide an promising opportunity to overcome hot cracking  when welding corrosion resistant Ni base alloys and therefore to increase the quality of welded joints. For heat reduced GMA welding of hot  crack sensitive nickel base alloy 625 (NiCr22Mo9Nb, 2.4856, UNS N06625) welding parameters and shielding gas were determined based on deposition welding to achieve a low spatter process and a good wetting behaviour. Regarding the realisation of further heat  reduced  welded joints multilayer deposition welds were performed to characterise and compare the occurrence of hot cracks and lack of fusion  depending on used GMA welding technique. For the evaluation of hot cracking sensitivity of alloy 625 the PVR test (programmed  deformation cracking test) is applied.