METALLURGICAL BACKGROUND TO THE DEVELOPMENT OF CREEP RESISTANT GRAVITY CASTING MAGNESIUM ALLOYS

摘要

Magnesium alloys, being the lightest structural metallic materials, are very attractive in automotive and aerospace industries. New alloys are required that would resist the increasingly onerous operating environment and that would provide more complex components with increased lifetime and reduced maintenance cost. The desire to achieve weight reduction of large powertrain components used by the automotive and aerospace industries has resulted in the development of new gravity casting alloys that provide a good combination of service properties and cost. The present paper addresses physical metallurgy principles that enabled to develop new alloys designated MRI 201S, MRI 202S and MRI 203S. New alloys are designed for applications up to 250-300℃ and have excellent mechanical properties, corrosion behavior and creep resistance in T6 condition. In addition, paper will also highlight some practical applications that illustrate the capabilities of the newly developed alloys.