Ordered C vacancies in titanium carbides: a correlation between crystal structure and the effects on oxidation behavior at elevated temperature

TL;DR

This study reveals how ordered carbon vacancies in titanium carbides influence initial oxidation behavior in titanium alloys, linking crystal structure to oxidation resistance through experimental and simulation analyses.

Contribution

It introduces the novel finding that ordered C vacancies affect early oxidation processes, supported by combined microscopic and computational methods.

Findings

Ordered C vacancies impact initial oxidation stages.

Micro-to-macro oxidation mechanisms are clarified.

Simulation and microscopy reveal structure-property relationships.

Abstract

It has been widely accepted that the introduction of titanium carbides into titanium-based alloys can significantly enhance the oxidation resistance due to their superior physicochemical stability at elevated temperatures. The present study reported for the first time that the ordered C vacancies within titanium carbides could lead to an uncommon phenomenon particularly at the very initial stage of oxidation. The intrinsic micro-to-macro oxidation mechanisms were systematically clarified with the aids of transmission electron microscope and ab-initio molecular dynamics simulation.