후방압출 공정에서 금형과 제품의 변형관계

Relation of Deformation between Die and Product in Backward extrusion

The die for cold forging gets a ver high axial load and radial pressure during processing and hence deforms considerably in the radial direction. This radial deformation of die becomes a important factor influencing the dimensional accuracy of a product. In order to obtain a product with highly accurate dimension therefore it is essential to acquire some information on elastic deformation of the die and the product. The study has been performed for the relation of the deformation between a die and a product in backward extrusion. The strain of the die has been given by the simple experiment using the strain gauges attached to the outer surface of the die. Also the history of the deformation of the die and the product has been given by the experiment and Lames' formula. The results has been compared with the previous another method. The study has given useful results for the deformation history of the die and the product through the experiment and Lame's formula in backward extrusion which can be applied in the die design for the product with accurate dimension