Özbek, Onur2023-07-262023-07-2620230025-53002195-8572https://doi.org/10.1515/mt-2022-0277https://hdl.handle.net/20.500.12684/12258This study aimed to improve mechanical properties, which decreased in the weld area, with deep cryogenic treatment at different holding times. In the study, firstly, the formation of heat damaging the welding area was observed. The temperatures in the welding zone were measured on the shoulder with a thermal camera, on the material surface, and inside the material with a thermocouple. The effects of these temperatures during welding on the surface topography and mechanical properties were investigated. The effect of tempering heat treatment after deep cryogenic treatment applied for 6, 12, 18, and 24 h was investigated. It has been observed that tempering after cryogenic treatment applied to 7xxx series aluminum alloys reduces the hardness of the nugget zone but increases the hardness in the heat unaffected zone. In addition, it was observed that deep cryogenic treatment applied at different holding times positively affected the hardness, tensile strength, and % elongation in the weld area.en10.1515/mt-2022-0277info:eu-repo/semantics/closedAccessAl 7050-T7451; Deep Cryogenic Treatment; Friction Stir Welding; Surface Topography; Weld Zone TemperatureWelded Az31 Magnesium; Stainless-Steel; Process Parameters; Surface-Roughness; Aluminum; Strength; Microstructure; Behavior; Joint; OptimizationArticle6533643772-s2.0-85149985216WOS:000945936400005Q2Q2