Options of crimping in a container and matrices of a special profile of axysymmetric hollow billets made of C60 steel

Abstract

Mathematical models were created using the finite element method and research was carried out on options for hot, semi-hot and cold crimping in a container and matrix of a special profile of axisymmetric hollow blanks made of high-carbon steel with variable wall thickness along the height. A plastic model of metal is used. Before hot and semi-hot crimping, the part of the workpiece was heated at the height to be deformed. The shape and dimensions of the initial blank for crimping were determined by calculation, which ensured the required dimensions of the product. The use of a container and a matrix of a special profile with a deforming surface made with ring protrusions made it possible to obtain a product in one pass for the considered options for crimping due to the reduction of the influence of frictional forces during molding. The rate of deformation was determined to maintain the mode of hot and semi-hot deformation during crimping. The dependence of the axial force on the deforming tool on the movement of the punch and the distribution of specific forces on the contacting surfaces was established. The use of cold pressing leads to an increase in the accuracy of the shape and dimensions of the product, a decrease in energy consumption and metal consumption. The final stress-strained state of the metal, the shape and dimensions of the product are determined. Based on the distribution of deformation intensity, an evaluation of the working of the metal structure by semi-hot and cold plastic deformation was carried out, and the yield point of the metal after crimping was predicted. On the basis of the simulation data, a design of the general appearance of the die equipment for cold crimping was developed.