Abstract: Based on the study results of the fatigue life distribution, the fatigue strength distribution characteristics of a HSLA steel was studied in this paper, and the fatigue strength distribution has been derived from the conversion relationship between the fatigue life distribution and the fatigue strength distribution. Research results show that the fatigue strength distribution is not normal but skew. For the above distributions, the P-S-N space curved surface which expresses the fatigue failure probabitity was drawn, and the curved surface will play an important role not only in practice but also in theory.

Key words: 低合金高强度钢, 疲劳强度