• 한국정밀공학회지
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• 제13권4호
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• pp.61-66
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• 1996

The subsequent recrystallizations technique, and experimental strain measurement method by use of recrystallization phenomena, has been successfully applied for the observation of machined surface plastic zones with equivalent plastic strain .epsilon. .geq. 0.5, 0.12 and 0.02 of type 304 stainless steel. The depth of the zone with .epsilon. .geq. 0.5 is very small, 10-15 .mu. m, while those with .epsilon. .geq. 0.12 are 100-200 .mu. m and 200-450 .mu. m, respectively. The depths increase with increasing depth of cut and with decreasing rake angle. The relation between the depth of the zones and the cutting paramenters is shown. The deformation state ahead of the quick-stop cut was also well visualized by the technique.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.988-991
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• 2001

Plastically deformed layer influences the mechanical property of the mechanical element such as creep hardening, microscopical crack and stress corrosion destruction. Therefore, the property so called the surface integrity has to be considered, and the machined surface including plastic deformation, distribution of stress has to be conducted quantitatively. This paper explains the orthogonal cutting, and made an orthogonal cutting model using the finite element method, then analyzed cutting power, plastic deformation of workpiece. It introduces the developed subsequent recrystallizations technique for measurement of the plastic strain of machined surface, and verified the technique.

• 한국기계가공학회지
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• 제2권3호
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• pp.69-75
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• 2003

Plastically deformed layer influences the mechanical property of the mechanical element such as creep hardening, microscopical crack and stress corrosion destruction. Therefore, the property so called the surface integrity has to be considered, and the machined surface including plastic deformation, distribution of stress has to be conducted quantitatively. This paper explains the orthogonal cutting, and made an orthogonal cutting model using the finite element method, then analyzed cutting power, plastic deformation of workpiece. It introduces the developed subsequent recrystallizations technique for measurement of the plastic strain of machined surface, and verified the technique.

• 한국정밀공학회지
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• 제15권4호
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• pp.141-147
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• 1998

A plastically deformed layer in the precision machined surface affects in various forms the physical properties of machined components such as the fatigue strength, the dimensional instability, microcracks and the stress corrosion cracking. These physical properties, so called surface integrity, are very important for designing highly stressed and critically loaded components. Typical plastic strains in the precision machined surface are very difficult to measure, since they are located within a very short distance from the surface and they change very rapidly. A new way is suggested to determine the residual strain in plastically deformed materials by analyzing the plastically deformed layer after a subsequent recrystallization process. This investigation is to explore a new technique for measuring plastic strain in machining applications, and in particular, to and the effect of cutting parameters(rake angle, depth of cut, specific cutting energy), on the plastic strains and strain energy.