• Proceedings of the Korean Society of Laser Processing Conference
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• 2006.06a
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• pp.35-40
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• 2006

Laser welding is high power density welding method which is higher speed and productivity, lower thermal deformation, without material restrictions for car body welding. But, in case of zinc coated sheet metal welding, the gap is needed $0.1{\sim}0.2mm$ to avoid weld bead blowup. This paper describe that it used dimple and pressure roller tool to improve laser welding quality for 3-layer zinc coated sheet metal.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1997.04a
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• pp.1-5
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• 1997

The plane surface rolling, one of the plastic working process, good surface condition due to increase of surface roughness and hardness. It is well known that mechanism of surface rolling depends upon rolling conditions such as rolling speed, contact pressure, step length of rolling, the shape of roller and mechanical properties of material. In this study, the optimal value of the above parameter on the surface roughness were investigated by using the rolling tool with NACHI 6000ZZ ball bearing outer races on machine structure carbon steel[SM45C]

• Journal of the korean Society of Automotive Engineers
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• v.8 no.3
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• pp.68-76
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• 1986

The surface rolling method which is one of the plastic deformation processes increases the surface roughness and hardness of materials. In this study, three NACHI6000 ZZ bearing were used for surface rolling tool on the mild steel and high carbon steel. The purpose of this study is to investigate the effects of rolling speed, feed rate and contact pressure on the surface roughness. The following results have been obtained with the mild steel and high carbon steel. 1. The roller finishing method has increased surface roughness from 2.4 .mu.m Ra at initial ground surface to 0.17 .mu.m Ra-0.4 .mu.m Ra. 2. The contact pressure has influenced greatly on the surface roughness. There is an optimal contact pressure. 3. As the rolling speed and the feed rate decrease, the surface roughness improves. 4. The optimal contact pressure for the good surface roughness of SS40 and STC 3 has been at 213 Kgf/Cm$^{2}$ and 220 Kgf/Cm$^{2}$ respectively.

• Journal of the korean Society of Automotive Engineers
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• v.9 no.5
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• pp.57-65
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• 1987

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 finishing after grinding The optimal surface roughness of SS41 steel can be obtained at the contact pressure of 210 kgf/cm$^{2}$. 2) At the contact pressure range of 200kgf/cm$^{2}$-210kgf/cm$^{2}$ for optimal surface roughness, The surface hardness increased to Hv200-Hv240 from Hv 125 before surface rolling. 3) Within the diameter variation of 13 .mu.m the surface roughness and the surface hardness were increased, but out of variation of 14.mu.m. The surface roughness become worse and the surface hardness was increased.

• Journal of the Korean Society of Safety
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• v.2 no.1
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• pp.31-41
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• 1987

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 $210kgf/cm^2$. But, Better surface roughness can not be expected, Due to flaking phenomena at more than 300 kgf/cm of contact pressure. 2) At the contact pressure range of $200kgf/cm^2{\sim}210kgf/cm^2$ 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 $13{\mu}m$ the surface roughness and the surface hardness were increased, but out of variation of $14{\mu}m$. The surface roughness become worse and the surface hardness was increased.