Formation of gallium coating on tungsten surface and its oxidation protection in air.

To address the poor high-temperature oxidation resistance of tungsten, a new high temperature protective gallium coating (O Ga) is designed in this paper. This O Ga material is modified with liquid metallic gallium by a mechanical stirring process, and a mixture of Ga x O y (Ga 2 O 3 and Ga 2 O) and Ga is obtained. Not only does it have good flexibility and adhesion, but it can also be easily printed to form a coating on tungsten surfaces. After isothermal oxidation at 800 °C for 24 h, the weight gain of the coating sample is 0.96 mg·cm−2, much lower than that of tungsten. This is attributed to the oxidation of the gallium coating on the tungsten surface to produce a βGa 2 O 3 layer, which prevents oxygen contact with the internal O Ga and W substrates. In addition, the inherent flexibility of the intermediate layer of O Ga prevents a mismatch in the coefficient of thermal expansion (CTE) between the βGa 2 O 3 layer and the W substrate, ensuring the integrity of the coating. Gallium coatings are expected to be an alternative to conventional protection systems. • The gallium is used as a coating to protect tungsten from oxidation in high temperature. • The oxidation weight gain of the coating was only 0.96 mg·cm−2 in air at 800 °C for 24 h. [ABSTRACT FROM AUTHOR]