Thermodynamic Study on Initial Oxidation Behavior of TiAl-Nb Alloys at High Temperature

Abstract

The initial oxidation behavior of TiAl-Nb alloys was systematically investigated against the composition, temperature, and partial pressure of O2 with the CALculation of PHAse Diagrams (CALPHAD) technique. The mole fraction of each oxidation product at the initial oxidation stage of the alloys at the corresponding temperatures was predicted. The initial oxidation products of the alloys are oxides of Al, Ti, and Nb, with the oxidation order of Al, Ti, and Nb. As P(O2) increases, the Ti and Nb oxidation products move towards a high oxygen content, and the mole fractions of the Al and Ti oxides gradually decrease and increase, respectively. It was found that the temperature and partial pressure of O2 determined the types of the oxides and the oxidation order, while the concentration of Nb and Al determined the mole fraction of the oxides. The CALPHAD results are in good agreement with the experiments.

Theoretical study of the effects of alloying elements on TiO2/Ti2AlNb interface adhesion properties

“…27 Although the Ti element competes with Al and Nb elements in the oxidation process, the increase in oxygen partial pressure is conducive to the formation of TiO 2 . 28,29 This paper studies the effect of alloying on the adhesion properties of TiO 2 on the Ti 2 AlNb matrix.…”

A New Method for Preparing Titanium Aluminium Alloy Powder

“…Nowadays, the TiAl-based alloy is still recognized as a high-end material in the world [3,4]. Due to its high specific strength, high temperature resistance [5,6], corrosion resistance, oxidation resistance [7,8], and excellent biocompatibility, the TiAl-based alloy is widely used in the field of high-end materials in modern life [9,10]. For example, large aeroplanes, submarines, aerospace technology, and artificial bones [11][12][13].…”