Aluminum Science and Technology
Extrusion can be cold or hot, depending on the alloy and the method used. This article focuses on the direct hot extrusion and describes a typical sequence of operations for the direct extrusion of a solid section. It discusses the key variables of extrusion process, including extrusion speed and extrusion exit temperature. The article reviews the classification of extrusion presses: direct, direct for seamless hollow, and indirect. The functions of the press dies and tooling are presented in a table. The article discusses the extrusion of soft and medium-grade alloys, hard alloys, and aluminum-matrix composites. It reviews common aluminum extrusion defects, including surface defects, blisters, and internal cracking. The article concludes with a discussion on the drawing of solid section and aluminum tube.