Abstract
The push-pull fatigue behavior of a carbon steel S45C was studied by using the annealed, prestrained and strain-aged specimens. The prestrain was 5% or 10%. The aging treatment after straining was done by heating the specimens at 100°C, 250°C or 300°C. Under these conditions, S-N curves, the temperature rise of specimens during cyclic stressing and the repeated plastic strain range were discussed. As a result, it was found that the fatigue strength of the strain-aged specimen increased by about 34% at maximum in comparison with the annealed, and that the temperature rise corresponded with the increase of the repeated plastic strain range. In addition, the sum of the repeated plastic strain range of the strain-aged specimen was smaller than that of the prestrained or the annealed.
