Factors determining the durability of cold extrusion dies

Abstract

The factors, which influence on the implementation effectiveness of cold extrusion processes of steel billets are considered. Economic feasibility and effectiveness of the implementation primarily depends upon the durability of extrusion tools. The research results of the ways to increase durability of tools for cold extrusion, which performed in four different directions: improving the structure and fabrication technology of dies; billet surface preparation for extrusion; improving material properties of extrusion tools using heat treatment; improving deformability of billet material. The procedure of heat treatment which increases the lifetime of extrusion tools made of high-speed steel is considered. Moreover, the conditions of heat treatment for obtaining the uniform structure of globular pearlite in hot-rolled and extrusion with different degree steel for the deformability improvement are proposed. The results of the research have been tested and implemented in the manufacture of the bicycle brake sleeves.