Proceedings of the Korean Society of Precision Engineering Conference (한국정밀공학회:학술대회논문집)
- 1997.04a
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- Pages.460-464
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- 1997
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- 2005-8446(pISSN)
Numerical Investigation of Forming Limit of Coated Sheet Metals
코팅제의 변형한계에 대한 수치적연구
Abstract
By the used of a similar numerical method as in the previous paper, the forming limit stain of coatedsheet metals is investigated in which the FEM is applied and J2G(J/sab 2/-Gotoh's corner theory) is utilized as the plasticity constitutive equation. Coated two-layer sheets and sheets bonded with dissimilar sheets on both surface planes are stetched in a plane-strain atate, with various work-hardening exponent n-values and thicknesses of each layer. Processes of shear-band formation in such composite sheets are clearly illustrated. It is concluded that, in the coated state, the higher limiting strain of one layer is reduced due to the lower limiting stain of the other layer and vice, and does not necessarily obey the rule of linear combination of the limiting stain of each layer weighted according thickness.
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