Thermo-Mechanical Training of Stainless Steels to Improve Damping Capacity

The effects of thermo-mechanical training on damping capacity of two types of stainless steels, Fe-18Cr-8Ni (SUS 304) and Fe-25Cr-20Ni (SUS 310S) stainless steels, are studied. The thermo-mechanical training with bending deformation is adopted, since vibration manner in internal friction measurement is bending mode. An anisotropic damping capacity as well as hardness of samples is studied. It is found that deformation induced ε-martensite is observed for trained SUS 304 sample, while deformation twins are formed in the trained SUS 310S sample. It is also found that internal friction of SUS 304 sample is larger than that of SUS 310S sample. Increase in number of training results in an increase in the internal friction and hardness. In addition, anisotropic damping capacity is observed in the samples subjected the thermo-mechanical training. To be concluded, the thermo-mechanical training is useful for enhancement of both damping capacity and strength of SUS 304 and SUS 310S stainless steels.