| 2001 №07 (01) | 2001 №07 (03) |
The Paton Welding Journal, 2001, #7, 6-10 pages
Application of high-frequency peening to improve the fatigue resistance of butt welded joints in aluminium alloys
V.I. Trufyakov, V.A. Shonin, V.S. Mashin, D.S. Romanovsky
E.O. Paton Electric Welding Institute of the NASU 11 Kazymyr Malevych Str., 03150, Kyiv, Ukraine.Abstract
The boundaries of welds on 12 mm thick samples were subjected to high-frequency peening in order to improve the fatigue resistance of butt welded joints in aluminium alloy AMg6. It is shown that treatment effectiveness depends on the power of ultrasonic generator and converter applied for excitation of vibrations in an array of needle-shaped pins, as well as on pin diameter. The best results were obtained, using an ultrasonic unit of 0.3 kW consumed power with three pins of 5 mm diameter for the region of alternating stresses (Rs = -1-0) and four pins of 2 mm diameter - for the region of stresses of a constant sign (Rs > 0).
Keywords: welded joints, aluminium alloys, fatigue resistance, cold working, residual stresses
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