Shiraz University Iranian Journal of Science and Technology Transactions of Mechanical Engineering 2228-6187 38 M2 2014 10 01 EXPERIMENTAL STUDY ON MECHANICAL PROPERTIES AND MICROSTRUCTURES IN A 36 REPAIR BUTT WELDMENT 431 438 2506 10.22099/ijstm.2014.2506 EN Journal Article 2012 10 15 Welding is one of the usual assembling methods with various applications. The<br />different defects are generated during welding and also in service conditions. After inspection and<br />identifying the defects, the repairs are applied. Welding repair operation causes the mechanical<br />properties and the microstructures of weldment to change. In the present work the variations of<br />yield stress, hardness and microstructures in the A 36 repair butt specimens were investigated by<br />the experimental study. The welding technique was Tungsten Insert Gas method without using<br />filler. The specimens were cut from the welded plates using water jet method for avoiding heat<br />effect during the cutting. The low-carbon steel A 36 thin plate was used to construct the<br />specimens. This material has numerous applications to construct various structures and parts. The<br />specifications of specimens and tests were selected according to the standards. The tensile tests<br />were performed for four numbers of each specimen. The mean of yield stresses in the specimens<br />were reduced after the repairing through half- thickness of the butt welds. Moreover, the mean of<br />yield stresses in the specimens after repairing would be decreased if the welding voltage and<br />current increased. Reduction of the hardness in heat affected zone and variation of the phases and<br />grain size after repairing were other outcomes from testing on the specimens. https://ijstm.shirazu.ac.ir/article_2506_1674e871908daa0d31c64a8a61f37c0b.pdf