Doubled Fatigue Strength of Box Welds by Using Low Transformation Temperature Welding Material
The low transformation temperature welding material is developed to improve the fatigue strength by introducing compressive residual stress around weld. The developed welding material which contains 10% chromium and 10% nickel, begins to transform from austenite to martensite at about 180°C and finishes it at room temperature. During the transformation, the weld metal expands. This expansion induces the compressive residual stress around the welded part of 20 mm thick JIS SM49O steel plate. The magnitude of welding residual stress is estimated to be about -100 MPa for the developed joint, while that is about 500 MPa for the conventional one. The stress ratio effect due to the compressive residual stress makes the fatigue strength doubled. The fatigue limit for conventional box welds is 65 MPa, while that for developed one is about 130 MPa.
KeywordsResidual Stress Weld Metal Fatigue Strength Compressive Residual Stress Tensile Residual Stress
Unable to display preview. Download preview PDF.
- 1.W.W.Sanders, A.T.Derecho,and W.H.Munse, Effect of External Geometry on Fatigue Behavior of Welded Joints, Welding Journal 44:49s(1965).Google Scholar
- 2.J.W.Fisher, Fatigue Strength of Welded A514 Steel Beams, Proc. Conf. Fatigue Welded Structures 1, The Welding Institute, Abington, 135(1971).Google Scholar
- 3.A.Ohta, N.Suzuki,and Y.Maeda, Effect of Residual Stresses on Fatigue of Weldments, International Conference on Performance of Dynamically loaded Welded Structures, Welding Research Council, New York, 108(1997).Google Scholar
- 4.I.J.Polmear, Effect of Peening on the Fatigue Performance of Aluminum Alloy Fillet Welds, Mat. Forum 2:20(1979).Google Scholar
- 6.V.L.Trufiakov, P.P.Mikheev, Yu.F.Kudravstev and E.S.Stanukov,Ultrasonic Impact Treatment of Welded Joints, IIW Doc. XIII–1609–95,1(1995).Google Scholar