INTRODUCTION

The discussion of engineering properties of structural materials in this chapter assumes some familiarity with both the properties of standard structural steels and alloys and the basic behavior of steels as found in a variety of handbooks and textbooks. For example, the mechanical properties of structural and other steels are found in current editions of the Metals Handbook, desk edition (ASM International, Materials Park, OH 44073) or within the current American Society for Testing Materials (ASTM) Specifications, the most relevant being found in volume 01.04, Steel-Structural Reinforcing, Pressure Vessel, and Railway (American Society for Testing and Materials, 100 Bar Harbor Drive, West Conshohocken, PA 19428).

A review of the compositions and properties of the structural steels indicates that, in spite of the variety of specifications, most structural steels share the same basic composition: carbon contents of 0.10 to 0.30 percent, manganese contents of 0.5 to 1.3 percent, silicon contents up to 0.4 percent, and phosphorus and sulfur contents up to 0.05 percent (as residuals from the steelmaking process). For grades which require greater corrosion resistance, or for which greater strength or toughness is desired, alloy additions of copper, nickel, chromium, and molybdenum up to 0.7 percent may be employed.

The vast majority of these materials are not heat-treated, but rather their microstructure and properties reflect the hot rolling and air cooling cycles that result from the production of plates and shapes. Their metallurgical microstructure is coarser in...