Page 66 - Module DMV20173

4.0 BULK DEFORMATION PROCESSES

CHAPTER 4 : BULK DEFORMATION PROCESSES

4.1 INTRODUCTION

Metallic components can be shaped in a manner similar to the molding of pottery. The raw
material of a fundamental simpler shape is provided by a primary process like casting,
powder consolidation, earlier forming processes, or even by electric deposition. Metals

deform very much like soft clay or wax. Even in the solid state, permanent changes in shape
can be forced upon them by displacement of relative positions between neighboring material
points. To enforce these changes, external forces are applied. While soft plasticine can be

molded by tiny toddler’s fingers, for metal forming, specially constructed tooling, usually of
hard materials, are manipulated, sometimes by colossal machinery. A variety of bulk
deformation process, the equipment and tooling, and the concepts involved will be

discussed in this course. This will provide an understanding of the typical processes (rolling,
forging and extrusion) involved.

Figure 4.1 Some products of bulk defromation processes.

LEARNING OBJECTIVES

The objectives of this unit are to :

1. define the rolling, forging and extrusion process;
2. identify the range of rolled, forged and extruded products;
3. describe the suitable materials and design for rolling, forging and extrusion process;

4. differentiate the types of defects in rolled, forged and extruded plates and sheets;

BPLK 98 DMV 20173