Authors:
Tsukasa Shirafuji (Kobe Steel, Ltd., Japan),
Yuji Taniguchi (Kobe Steel, Ltd., Japan)
Abstract:
The fatigue strength of sintered steel is normally lower than that of conventional low-alloyed steel, such as JIS SCr420 and JIS SCM415 and so on,The fatigue strength of sintered steel is normally lower than that of conventional low-alloyed steel, such as JIS SCr420 and JIS SCM415 and so on, due to the porosities inside the material. However, it has been reported that tooth bending fatigue strength of sintered gears manufactured from 46F4H (0.5Ni-1.0Mo Pre-alloyed Steel Powder) is improved by surface-rolling and that the fatigue strength is equal to or higher than that of the gear manufactured from the wrought steel. In this study, we found that the reason why surface-rolled sintered steel gears have high fatigue strength is caused by both a decrease in size of the initiation fatigue crack due to eliminate the porosities in the vicinity of surface of the gear, and high compressive residual stress.
DOI:
https://doi.org/10.59499/WP225364378