Chapter 2 - Tolerances, Mechanical Properties, Physical Properties—A Review

Abstract

This chapter discusses the tolerances, mechanical properties, and physical properties. It also describes the importance of the interchangeability of parts to modern manufacturing. A tolerance is a designer–specified allowed variation in a dimension or other geometric characteristic of a part. The limits of size are the two extreme permissible sizes of a part between which the actual size must lie. Tolerances can be applied bilaterally. The chapter also covers mechanical and physical properties. A part's size, shape, and geometry, and the material's mechanical and physical properties, affect the choice of material–process combination. The chapter focuses on how the physical and mechanical properties of materials can affect the choice of process to be used to manufacture a part and how these properties can affect the ease or difficulty of creating the part via a particular process.