Introduction to Engineering Materials

 Engineering materials can be classified as (1) metallic materials and (2) non-metallic materials. Metallic materials are further classified as (1) ferrous metals,basically iron and iron alloys and (2) non-ferrous materials and alloys. Rubber,wood,concrete,ceramics,plastics etc. constitutes non-metallic materials.
 For any particular engineering application,  these materials are selected on the basis of working conditions to which it'll be subjected,ease of manufacturing and the cost factor. Alloys are preferred to pure metals for all engineering applications as pure metals are difficult to produce,in addition to that, they have poor strength in pure form.The various desired properties can be achieved by addition of different materials to form alloys.Alloys comprises of a base metal, more than 50% in content, and one or more alloying materials. The typical properties associated with working conditions are tenacity, elasticity, toughness and hardness and typical properties associated with manufacturing processes are ductility, malleability and plasticity. The various desired properties are determined by testing techniques. Tensile strength is determined by tensile test, ductility's by bend test, resistance to abrasion by hardness test, toughness by impact test, fatigue and creep by corresponding tests, etc.