Manufacturing – Forming and Shaping Processes
Learning Objectives
This chapter covers metal forming process common in part manufacturing and some principles of design for manufacturing for this manufacturing method. By the end of this chapter, reader will be able to:
- Describe the processes of metal forging, extrusion, rolling and drawing.
- Describe the types of sheet metal work.
- Apply principles of DFM for bulk metal forming and sheet metal work.
Metal forming is a process of shaping metal workpieces into desired geometries by applying controlled forces. Metal forming processes can be classified into bulk deformation and sheet metal forming, depending on the thickness-to-width ratio of the workpiece. Bulk deformation processes, such as forging, extrusion, and rolling, involve large plastic deformations and significant changes in the cross-sectional area of the workpiece. Sheet metal forming processes, such as bending, deep drawing, and stamping, involve relatively small thickness changes and shape the workpiece into a thin-walled shell.
Design for manufacturing (DFM) for formed metal parts involves considering the material selection, geometry, tolerances, surface finish, and process parameters of the metal forming processes. DFM can help to avoid defects, such as cracking, wrinkling, springback, and residual stresses, that may occur during metal forming. Implementing DFM can also reduce the number of operations, tools, and dies required for metal forming, thereby saving time and resources.
