a. The curves of bending P-S-N of 20crnimoh material with different survival rates of shot peened and non shot peened gears are obtained. The power function indexes of the two kinds of gears are similar, that is to say, the slope of oblique line of S-N curve of the two kinds of gears is similar.
b. It can be seen from the test results that the slope of S-N curve ofbending is not related to the surface residual stress, but to the factors such as gear module and gear width.
c. The bending fatigue strength of the tested gear after shot peening is 30% higher than that of the gear without shot peening.