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Initial material structure, welding parameters as well as subsequentprocessing or loadings can drastically influence the durability of welded partsfabricated from austenitic steels or super-alloys. Metallographic analysis performed ona considerable number of TIG welded joints between parts fabricated from austeniticsteels such as AISI 304, AISI 309, AISI 316 or INCOLOY 800 superalloy allowedidentification of different fracture types caused by processing factors: inadequategeometry of the joint, flaws inside the joint or on the heat affected zone (HAZ). Anothercategory of fracture causes is represented by the service conditions such as intercrystallinecorrosion or stress corrosion. The fracture mechanism has been analyzedalso as in connection with the processing by mean of cold deformation that was appliedafter the welding. Some representative examples are presented by mean ofmetallographic analysis on samples that contained cracks or fractures produced duringprocessing or in service. The analysis procedures, which were applied in differentstages of the fabrication route, permitted the identification of specific causes thatproduced fracture or formation of cracks.