新制御圧延(TMCP)型50キロ級高張力鋼溶接継手部の疲労強度とその評価(その2)

概要

論文の詳細を見る
The authors' previous report concerned the fatigue strength characteristics of high heat-input welded joints produced in TMCP type 50kgf/mm^2-class high-tensile steel plate 0.313 to 0.357 percent in carbon equivalence Ceq. With a view to improving the weldability (resistance to low-temperature cracking) or the toughness of HAZ of the high heat-input welded joint, a plan is under way for engineering to practicality the same TMCP type high-tensile steel plate still lower in carbon equivalence. Accordingly, the authors performed another study on the fatigue strength characteristcs of the high heat-input welded joints which were produced this time in the TMCP type high-tensile steel plate 0.25 to 0.30 percent in carbon equivalence, with the following results. (1) When represented in the form of S-N_f diagram, the high heat-input welded joints in the TMCP type high-tensile steel plate lower in carbon equivalence and those in the ordinary rolled 50kgf/mm^2-class high-tensile steel plate can be regarded as being equivalent in fatigue strength from the design standpoint. (2) Even if HAZ is subjected to a combination of softening and stress concentration, the resultant decline in fatigue strength of the welded joint is negligibly small for practical purposes.
社団法人日本船舶海洋工学会の論文
1985-03-22