Hot and cold bulk deformation processes

Abstract

Metals are initially produced by the refining of ores or scrap metal in furnaces. The molten metals or alloys are usually cast into ingots, slabs, or billets. Before metal goods can be manufactured, it is necessary to transform these cast metal forms into intermediate (or semifabricated) products like metal sheets, wire, and rods, which are the starting point for the manufacture of more complex products. Cold or hot bulk deformation processes like rolling, drawing, extruding, and forging which involve large scale plastic deformation are used for this purpose. Unlike sheet metal working where the changes in thickness are small, bulk deformation processes cause large changes in thickness, diameter, or other dimensions of the cast metal forms.