オーステナイト系ステンレス鋼の疲労強度に関する研究

(応力比および腐食環境の影響)

抄録

This paper showed the fatigue strength of base metal and butt welded joint of SUS304A austenitic stainless steel, especially fatigue strength of corroded welded joint by salty environment. The main results of fatigue tests of base metals and butt welded joints using SUS304A austenitic stainless steel were as follows;
(1) m-values which were the exponent of slope of S-N curve of base metal were 5∼15. This values were higher than JSSC standard-value m=3, so that JSSC standards estimated danger-side for fatigue strength under 1×10⁶ stress cycles. (2) The 2×10⁶ fatigue strength of no-corroded butt welded specimens fell to about 70% fatigue strength of base metal's ones. (3) The 2×10⁶ fatigue strength of corroded butt welded specimens fell to about 80% fatigue strength of no-corroded butt welded ones, and fell to about 55% of base metal's ones. And the 2×10⁶ fatigue strength of corroded and acted bending-moment specimens fell to about 70% of corroded butt welded ones, about 55% of no-corroded butt welded ones, and about 50% of base metal's ones.