2 - Theory for Alloy Design

Abstract

A variety of alloys and steels have been widely used from ancient times to modern times. Most of these materials have been developed relying on many trial-and-error experiments as well as the experience of each researcher. In the present supercomputer age, computer-aided alloy design is, however, needed to save time and cost necessary for alloy development. To meet the needs of the times, a theory for alloy design has been developed recently. In this chapter the theory is explained, in particular, focusing on the philosophy of alloy design. The necessity of new alloying parameters is first explained for the design of commercially available alloys with multiple components, since we do not have any alloying parameters despite a long history of metallurgy and metal science. Two alloying parameters are derived using the DV-Xα molecular orbital method. In this chapter, a new approach to alloy design is presented focusing mainly on the alloying parameters and the DV-Xα molecular orbital method.