Authors : Suppachai Chainarong, Siva Sitthipong, Chaiyoot Meengam, Prapas Muangjunburee and Muhamad Tehyo
Abstract: This research studies the fatigue behavior of welding surface of Low Alloy Steels with Shield Metal Arc Welding (SMAW), Metal Active Gas Arc Welding (MAG) and FluxCored Wire Arc Welding (FCAW) process. For reduction of residual stress, the test specimens were heated to a temperature of 350°C before welding and heated to 550°C for 1 h after welding. The test specimens were welded by Shield Metal Arc, Gas Metal Arc and FluxCored Arc welding process. The study on fatigue strength shows that the weld metal produced by FluxCored Arc welding process gives the best fatigue strength but slightly lower than that of the Low Alloy Steels AISI 4340. For failure analysis and assessment on lifespan of shafts that were made from high tensile steel AISI 4340 which are used in transmission of electric cable shovel, it gives the benefits of choices to select the most suitable welding process. By studying on cracking surface and mechanical problem solving process in deteriorations from fatigue under full loading capacity of the working electric cable shovel, it reveals that the stress concentration area initiated the rupture. The assessment on the useful life of transmission shafts in the form of cycle loading indicates that welding repair process with welding resurfacing by FluxCored Arc welding process gives the longest lifespan.
Suppachai Chainarong, Siva Sitthipong, Chaiyoot Meengam, Prapas Muangjunburee and Muhamad Tehyo, 2016. A Comparative Study: Life Extension of Weld Surfacing of AISI 4340 High Tensile Strength Low Alloy Steel. Journal of Engineering and Applied Sciences, 11: 1644-1649.