REDUCTION OF COLD-SHEET STAMPING TRANSITIONS IN THE MANUFACTURING OF HOLID CONE PRODUCTS FROM COPPER

Abstract

The paper considers the reduction of the number of transitions in cold stamping of hollow cone products from copper
sheet billets, which are stamped by drawing in four transitions according to the traditional technology. In the first step, a semi
finished product with conical and cylindrical parts is produced by drawing in a cone die. In the second step, the cylindrical part
is crimped and the finished cone product is obtained. Mathematical models were created by the finite element method using the
DEFORM-2D program and an elastic-plastic model of the metal, and a computational analysis of the stretching and
compression transitions was performed. The modeling of compression took into account the accumulated deformations and the
exhausted plasticity resource in the deformed metal after stretching. For drawing, a special profile matrix with a conical surface
in the form of protrusions and depressions was used, which made it possible to reduce the drawing force and increase the degree
of deformation and perform drawing in one pass. For two transitions of the product forming, the dependence of deformation
forces on tool displacement was determined. The distributions of stress components, deformations, exhausted plasticity resource,
and the shape and dimensions of the semi-finished product after drawing were determined. Similar data were obtained for the
compression transition. The development of metal structure by cold plastic deformation is estimated by the distributions of
deformation intensity in the volumes of semi-finished product and product.