鋼ローラの転がり疲れに及ぼす表面改質処理の影響 : 純転がり接触の場合

抄録

Surface modified rollers by electroless Ni-P alloy plating and sulfurizing were fatigue-tested under a pure rolling contact condition. The fatigue lives of both surface modified rollers were longer than that of the non-coated rollers and the fatigue strength of the sulfurized rollers was the highest. The influence of elastic modulus of a plated layer on the contact pressure and the subsurface stresses was examined with numerical analyses. The contact pressure and the subsurface stresses of a roller covered with a plated layer, whose elastic modulus was smaller than that of the substrate, were smaller than those of a non-coated roller, especially at the edge of the contact width. The conformity by the wear of the plated layer led to the reduction of the contact pressure and the subsurface stresses at the edge of the contact width. The reason why the fatigue strength of the surface modified rollers were greater than that of the non-coated rollers could be due to the smaller contact pressure and the smaller subsurface stresses.