연삭가공된 강재의 표면 Rolling 시 가압력이 표면 조도에 미치는 영향 = An Effect of Load on Surface Roughness on Surface Rolling of Ground Mild Steel

다국어 초록 (Multilingual Abstract)

The surface rolling method which is one of the plastic deformation processes increases the surface roughness with reduction of diameter and hardness.
In this study, three NACHI 6000 ZZ bearing were used for surface rolling tool on a mild steel.
The following results have been obtained with the mild steel.
1) The load is major factor in getting fine surface roughness of roller fininshing after grinding.
The optimal surface roughness of SS40 steel can be obtained at the contact pressure of 210 kgf/㎠
But, Better surface roughness can not be expected, Due to flaking phenomena at more than 300 kgf/㎝ of contact pressure.
2) At the contact pressure range of 200kgf/㎠∼210kgf/㎠ for optimal surface roughness, The surface hardness increased to Hv 200 ∼ Hv 240 from Hv 125 before surface rolling.
3) Within the diameter variation of 713㎛ the surface roughness and the surface hardness were increased, but out of variation of 14㎛. The surface roughness become worse and the surface hardness was increased.