STUDY OF ENHANCEMENT OF FATIGUE STRENGTH FOR WELDED STRUCTURE DUE TO FLAME LINE HEATING

Fatigue cracks often initiate at the fillet weld toe of structural discontinuity parts in welded structures. Large tensile residual stress usually acts in these parts in as-weld condition. As the tensile residual stress forces fatigue strength to decrease, it is intended that tensile residual stress turns to compressive residual stress for the enhancement of fatigue strength. A simplified method of obtaining the flame line heating condition for maximum reduction of residual stress was investigated from a previous study of flame line heating and welded residual stress. As a result, it was confirmed that residual stress with the order of yield stress ( Y) in the as-weld condition at boxing weld toe, changes to compressive residual stress with the order of -0.5 Y by flame line heating for HY-50 steel. Fatigue tests of boxing welded joints using HT-50 steel were carried out both for as-welded joints and flame heated joints. A drastic improvement of fatigue strength was observed after flame line heating.

  • Supplemental Notes:
    • J Soc Naval Arch Japan, v 176, Dec 1994, p 465 [9 p, 10 ref]
  • Authors:
    • Toyosada, M
    • Yamaguchi, K
  • Publication Date: 1994

Language

  • Japanese

Subject/Index Terms

Filing Info

  • Accession Number: 00710747
  • Record Type: Publication
  • Source Agency: British Maritime Technology
  • Files: TRIS
  • Created Date: Aug 14 1995 12:00AM