At present, the main methods for preparing boron carbide coating include vapor deposition plasma spraying gas conversion reaction - sintering plasma immersion ion treatment and so on. The vapor deposition and plasma spraying require expensive equipment and have shadow effect, so it is difficult to uniformly coat the complex substrate surface. Reaction-sintering process requires high sintering temperature and harsh conditions. The boron carbide coating produced by plasma immersion ion treatment is very thin, with a thickness of less than 200nm, which limits its application prospect.

Therefore, for boron carbide coating to be widely used in many fields, it is necessary to develop a preparation method of boron carbide coating with simple technology and suitable for surface coating with large area and complex shape.