"The numbers and types of alloys for posthodontic restorations have increased dramatically over the past 25 years, making selection of an alloy for a given clinical situation difficult. factors such as cost, the need for better strength, and worries about alloy corrosion have pressured the alloy market to change significantly. A number of properties -including yield strength, hardness, elastic modulus, microstructural phases, grain size, corrosion performance, coefficient of thermal expansion, oxide color, and melting range- are relevant to the proper selection of an alloy for a given clinical problem."