Journal of Inorganic Materials ›› 2017, Vol. 32 ›› Issue (12): 1269-1274.doi: 10.15541/jim20170101

• Orginal Article • Previous Articles     Next Articles

YSZ- Ti3AlC2 Thermal Barrier Coating and Its Self-healing Behavior under High Temperatures

Xu-Xuan SUN(), Hong-Fei CHEN(), Guang YANG, Bin LIU, Yan-Feng GAO()   

  1. School of Materials Science and Engineering, Shanghai University, Shanghai 200444, China
  • Received:2017-03-02 Revised:2017-04-16 Online:2017-12-20 Published:2017-11-21

Abstract:

Ti3AlC2 acting as a new self-healing agent was added into yttria-stabilized zirconia (YSZ) thermal barrier coatings. By atmospheric plasma spraying (APS), thick coatings were prepared using YSZ-Ti3AlC2 mixing powder. To observe oxidation and self-healing behavior, cracks were prefabricated on the surface of YSZ-Ti3AlC2 coating by uniform external load. The prepared samples were then isothermal treated at 1050℃ in air. The phase and morphology evolution of the coatings, as well as the self-healing behavior were investigated via several analyzing methods. The results showed that a part of Ti3AlC2 was decomposed into TiC after spraying and a double layered structure composed of a TiO2 outer layer and a TiO2+Al2O3 inner layer was formed after isothermal treatment. In the process of self-healing, oxidation of the healing agent in the coating led to the growth of alumina and low-density titanium oxide in the cracks. These oxides gradually filled the cracks due to the diffusion-controlled oxidation. Meanwhile, the compressive stress induced by the volume expansion of TiO2 growth in the crack enhanced the healing effect. And eventually the prefabricated cracks were healed.

Key words: thermal barrier coatings, atmospheric plasma spraying, self-healing

CLC Number: 

  • TQ174