Ultrasonic Measurement of Residual Stresses in Welded Elements of Ship Structure
The objective of the study described in this paper is to identify the residual stress distribution and relaxation in standard welded specimens as well as in a large-scale welded panel imitating the critical, from the fatigue point of view, zones of ship structure. The residual stresses were measured after welding and in the process of fatigue loading of welded elements by the UltraMARS system that is based on using ultrasound. The measurements had shown that the maximum residual stresses near the welds (4-5 mm away from the weld) reach levels 290-320 MPa that are close to the yield strength of considered material both in welded specimens and in the large scale panel. Analysis of residual stress relaxation in the welded panel under the action of cyclic loading confirmed the fact that within the interval of applied stress ranges corresponding to the multi-cycle region of loading of the welded joints, the relaxation of residual stresses occurs mainly during the first cycle.
R. L. Burguete, M. Lucas, E. A. Patterson, S. Quinn
Y. Kudryavtsev et al., "Ultrasonic Measurement of Residual Stresses in Welded Elements of Ship Structure", Applied Mechanics and Materials, Vol. 70, pp. 273-278, 2011