Liang-Bin Liu

Thermodynamic Modeling of the Au-Bi-Sb Ternary System

Based on the available experimental information, the Au-Bi binary system has been thermodynamically assessed using the CALPHAD method. The solution phases, including liquid, fcc_A1, and rhombohedral_A7, were modeled as substitutional solutions, while the intermediate compound Au2Bi was described as a stoichiometric compound. Combined with the available thermodynamic parameters of the Au-Sb and Bi-Sb binary systems, a thermodynamic description of the Au-Bi-Sb ternary system has been developed to reproduce the reported phase equilibria. The liquidus projection and several vertical and isothermal sections of this ternary system have been calculated, which are in reasonable agreement with the reported experimental data.

High-efficiency combinatorial approach as an effective tool for accelerating metallic biomaterials research and discovery.

A high-efficiency combinatorial approach has been applied to rapidly build the database of composition-dependent elastic modulus and hardness of the Ti-Ta and Ti-Zr-Ta systems. A diffusion multiple of the Ti-Zr-Ta system was manufactured, then annealed at 1173K for 1800h, and water quenched to room temperature. Extensive interdiffusion among Ti, Zr and Ta has taken place. Combining nanoindentation and electron probe micro-analysis (EPMA), the elastic modulus, hardness as well as composition across the diffusion multiple were determined. The composition/elastic modulus/hardness relationship of the Ti-Ta and Ti-Zr-Ta alloys has been obtained. It was found that the elastic modulus and hardness depend strongly on the Ta and Zr content. The result can be used to accelerate the discovery/development of bio-titanium alloys for different components in implant prosthesis.