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http://dx.doi.org/10.5781/KWJS.2013.31.4.73

Bead Shape and Conditions of Friction Stir Processing to Improve Fatigue Strength  

Park, Jeong-Ung (Dept. of Civil Engineering, Chosun University)
An, Gyu-Baek (Technical Research Laboratories, POSCO)
Kim, Heung-Ju (Plant Research Center, Research Industrial Science and Technology)
Jo, Byeong-Cheol (Dept. of Civil Engineering, Gradurate School of Chosun University)
Publication Information
Journal of Welding and Joining / v.31, no.4, 2013 , pp. 73-79 More about this Journal
Abstract
Burr grinding, Tungsten Inert Gas (TIG) dressing, ultrasonic impact treatment, and peening are used to improve fatigue life in steel structures. These methods improve the fatigue life of weld joints by hardening the weld toe, by improving the bead shape, and by creating the compressive residual stress. In this study, a new post-weld treatment method improving the weld bead shape and metal structure at the welding zone using Friction Stir Processing (FSP), a welding process, is proposed to enhance fatigue life. For that, a pin-shaped tool and processing condition employing Friction Stir Processing (FSP) is established through experiments. Experimental results revealed that fatigue life is improved by around 50% compared to as-welded fatigue specimens by reducing the stress concentration at the weld toe and by generating a metal structure finer than that of flux-cored arc welding (FCAW).
Keywords
Friction stir processing; Fatigue strength; Bead shape; Butt welding; Stress concentration; Microstructure;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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