2010 年 28 巻 4 号 p. 355-361
The purpose of this study, it is that achieve high performance and high function of the industrial product under the low cost. The fatigue test of SUS304/S35C and SUS304/S55C friction welded joints with flash was investigated by rotating bending fatigue test.
The experimental results as follows;
1) The broken part of friction welded joints of SUS304/S35C and SUS304/S55C was changed by amplitude stress, its part was toe of flash of S35C and S55C when amplitude stress was low. And, in the case of the high amplitude, it was specimen parallel part of SUS304.
2) The stress concentration factor of toe of flash of S35C and S55C was increased with increase of upset pressure. This tendency was slightly in the case of SUS304, And in the case of carbon steel, it was increased remarkably with increase of carbon.
3) When amplitude stress was low, broken part of S35C and S55C joints was toe of flash, these fatigue strength was decreased remarkably with increase of upset pressure. This main reason was increased of the stress concentration factor.
4) When amplitude stress was high, broken part of SUS304 was parallel part and this reason was by red-hot. These reason occurred heat by internal friction and low thermal conductivity. But, this red-hot was prevented completely with dropping of water of 50ml/min.
5) When parallel part length of SUS304 was less than 25mm, amplitude stress of broken by red-hot was increased with decrease of parallel part length.