Experimental study on the performance of superfinish hard turned surfaces in rolling contact

In this study, specimens of AISI 52100 with hardness of 62-63 Rc were hard turned using different cutting parameters. Surface roughness, residual stress, and micro-hardness were measured. The workpieces were then tested for the rolling contact fatigue life under several maximum Hertzian contact stresses. Results indicate that the choice of the cutting parameters greatly affects the surface integrity aspects of the hard turned parts and consequently, the fatigue life. For the range of experiments performed, it is found that varying the cutting parameters largely changes the fatigue life by a factor up to 40 times. The repeatability of the fatigue life of hard turned workpieces under the same loading is found to be much more consistent than that of ground workpieces.