Evaluation and comparison the effect of heat treatment on mechanical properties of NiCrBSi thermally sprayed coatings

Abstract

Purpose This study aims to investigate the effect of post heat treatment on mechanical properties of NiCrBSi coatings, which were applied on 316L stainless steel using high-velocity oxygen-fuel (HVOF) and flame spray techniques. Design/methodology/approach The properties of coatings were investigated by metallographic characterizations as well as wear, micro-hardness and adhesion tests. Findings The micro-hardness results showed that the coatings considerably increased the sub-layer hardness. In addition, regarding the wear test results, it can be seen that heat treatment increased wear resistance of the coatings. These thermal sprayed coatings are usually re-melted by post heat treatment, leading to improvement in tribological properties. The results obtained revealed that re-melting procedure improved the metallurgical bonding in the substrate\coating interface. Originality/value Microstructure defects resulting from thermal spraying such as pores and unmelted particles can be eliminated by post heat treatment. This process can considerably improve the corrosion and wear resistances of the thermal sprayed coatings.

Influence of heat treatment on surface properties of HVOF deposited WC and Ni-based powder coatings: a review

“…The most performing and best suitable properties for a particular application can be addressed and attained by optimizing the microstructure. Post-treatment of thermally [69]. The amount of non-melted particles was also not reported in heat-treated coatings, and heat treatment also eliminates boundary length among splats.…”