1. Introducti on
A wide spectrum of engineering materials ranging from metals and alloys to highly advanced ceramics,
polymers and composites find application in strategic sector. The designer working in these industries goes
through an elaborate evaluation of various characteristics of materials, while making his choice for intended
application. Among the important criteria the designer adopts for material selection are – high strength to weight
rat io, funct ional and environmental s tability as well as high degree of reliability. Adequate knowledge of s ervice
requirements and detailed informat ion regarding material capabilit ies are absolutely es s ent ial for the des igner to
make right choice of materials.