• Proceedings of the Korean Society of Precision Engineering Conference
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• 1995.10a
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• pp.113-116
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• 1995

In this experimental study,aluminum hotforging was conduct to get superior pistion to cast piston. Cast structure of billet is destroyed, harmful defects is removed by forging process. We proposed the direction od die design by observing formability of product according to die shape. The microstructure of forged products with different preform was investigated to determine inital billet shape. We proposed appropriate heat treatment condition for improvement of mechanical properties.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.4 no.1
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• pp.36-41
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• 2003

The purpose of this study was to find a way to lengthen the life of hot closed forging die. The fluid interpretation on the plastic deformation of billet of billet was performed by finite element method. And design modification on the impression shape was also performed. The defaced part on the impression surface was mended by the developed build-up welding method. The die life was 3,000 units but alter the procedure it was lengthened up to 5,000.