Repair Techniques Of Dissimilar Metal Welds Between Stainless And Unalloyed Steel Načini popravila varov pri varjenju raznorodnih jekel Marjan Suban, Borut Bundara, Robert Cvelbar Institute of metal constructions, Mencingerjeva 7, 1001 Ljubljana, Slovenia Abstract: Dissimilar metal welds are common to all industries and their service performance is often crucial for the function of welded part. Improper selection of filler material for welding dissimilar joints between austenitic stainless steel and unalloyed steel lead to several problems, which can all results in weld failure. From known practice, there were cases where instead of recommended filler material from group of stainless steel, unalloyed steel filler material was selected for welding. Due to martensite grain structure of the weld, hardness limit is exceeded. Formation of hard weld with low ductility accompanied by the diffusion of hydrogen, always present serious risk of cracking. Due to these reasons, welded joints need to be repaired to achieve suitable mechanical properties and quality. Emphasizing possibilities and limitations imposed by unsuitable weld, base, and filler metal metallurgy, some methods of repair, involving weld removal or weld reinforcement, are more in detail described in the presented paper. Keywords: welding, weld reinforcement, stainless steel, unalloyed steel