• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 1999년도 춘계학술대회논문집
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• pp.153.1-156
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• 1999

Based upon the experimental data from multi-stage tensile loading at angles to the rolling direction of steel sheets, anisotropic hardening rules are proposed. Experiments show that orthotropic anisotropy is maintained and the orientations of orthotropy axes are changed during tensile loading. A phenomenological model is proposed which includes the rotations of orthotropy axes, work hardening and kinematic hardening. Using the model, uniaxial tensile stress, R-value and tensile necking strain are predicted and compared with the experimental data.

• 한국해양공학회지
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• 제11권2호
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• pp.57-69
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• 1997

The objetive of this study is to compare the mechanical proprties of 6000 series Al-Mg-Si aluminum alloy (AC120) with 5000 series Al-Mg aluminum alloy (TG25), and to investigate the influence of corrosion solution for fatigue life. Comparing of TG25 and AC120 alloy sheets, TG25 alloy sheets showing higher plastic ratio and total elongation have better formability than AC120 alloy sheets. The hardness of nugget area was a little higher than that of base metal area. Also, grain coarsening was observed in HAZ(Heat Affected Zone). In a corrosion fatigue experiment, the fatigue life decreased as concentration increased, when a dipping time was constant. The life decreased as dippling time increased, when a concentration was constant.