Enhanced oxidation resistance in Ti₃AlC₂ via selective self-healing

Ti₃AlC₂ is anticipated to be used in high temperature fields owing to its excellent dual characteristics of metal and ceramic. However, a critical challenge arises from the inevitable formation of pores within bulk Ti₃AlC₂ during the sintering process, which are detrimental to its oxidation resistance performance. Herein, the high temperature self-healing and selective oxidation characteristics of Ti₃AlC₂ are combined, and the selective self-healing of Ti₃AlC₂ is realized by controlling the pre-oxidation atmosphere, i.e., the pores are effectively filled with α-Al₂O₃. As a result, the oxidation resistance of Ti₃AlC₂ was significantly enhanced by 860 times. This method provides a simple and economical way to improve the high-temperature oxidation resistance of Al-containing MAX phase materials represented by Ti₃AlC₂.