Outstanding anti-oxidation performance of boride coating under high-temperature friction

The interactions between oxidation and external friction usually cause accelerated failure of materials by repeated destruction of protective oxide layers. In this work, we discovered that in a unique boride coating fabricated by thermal spraying pre-treated WB-Co powder on steel, the friction-induced microstructural defects at elevated temperatures can be self-repaired by plastic flow and redistribution of nanocrystalline WO3, CoWO4 and molten B2O3. Besides, strong mechanical support from the underlying coating was favorable for slowing down the oxide growth. Based on understanding of the oxidation-resistance mechanisms of this oxide-boride system, a new strategy for developing highly anti-oxidative ceramic-based materials is proposed.

Automated summary

In this study, it was found that a boride coating fabricated by thermal spraying has the ability to self-repair friction-induced defects at elevated temperatures through plastic flow and redistribution of nanocrystalline particles. Additionally, strong mechanical support from the underlying coating slows down the rate of oxidation growth, proposing a new strategy for developing highly anti-oxidative ceramic-based materials.