| To develop inexpensive bearing steel with improved resistance to rolling contact fatigue, the influence of applied load on rolling contact fatigue of C-Mn induction-hardened bearing steel has been investigated under the axial load conditions of 310㎏f∼605㎏f(3040N∼5933N). Fatigue tests were conducted at a shaft speed of 1,700 rpm with circulating lubricant through filtered-pump feed system. It was found that microhardness in the subsurface below the raceway of rolling contact fatigued specimens was increased in comparison with that of induction-hardened layers. As the applied load during rolling contact increased from 310㎏f to 605 ㎏f, the depth of microhardness-increased region was increased from about 300㎛ to 500㎛ from surface, respectively. This resulted from both strain hardening and transformation induced plasticity of retained austenite. It was also found that increased amount of retained austenite decomposed during rolling contact fatigue resulted in improved resistance to rolling contact fatigue under the different loaded conditions in the range of 310㎏f∼605㎏f. (Received July 19, 1994) |
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