1.3 - The molecular orbital approach and its application to biomedical titanium alloy design

Abstract

Recently, the molecular orbital approach to alloy design has made remarkable progress. This approach is constructed on the basis of the electronic structure calculations of alloys by using the DV-Xα cluster method. New alloying parameters are determined for the first time from the calculations of titanium alloys and employed for predicting phase stability and alloy properties in a reasonable manner. For example, it is shown that any titanium alloy can be classified into either the α, α+β, or β type from the alloy composition by using the alloying parameters. The corrosion resistance is also treated along this approach. A concrete way of alloy design is explained using an example of high-strength β-type Ti alloys. Then, practical alloy design based on this approach is reviewed, focusing on the biomedical titanium alloys. Recent progress in this approach is also presented to design titanium alloys for biomedical applications.