Studies on wear and microstructure assessment of WC-Co reinforced iron based HVOF coating

Abstract

This research work uses a High-Velocity Oxy Fuel (HVOF) system to create a cermet based WC-10Co reinforced with a durable Iron-based (FeNiCrMo) advanced composite coating to resist high-temperature sliding wear on an ASTM-SA213-T11 steel substrate. Metco 41C (70%) + WC-10Co (30%) were mechanically blended. Then, feedstock was utilized by the HVOF system to create coatings. The base alloy and the coatings were subjected to various metallurgical and mechanical characterizations. Dry sliding wear test of base alloy and coating, were evaluated using the pin-on-disc device. The test was performed by varying parameters of load 10 N and 20 N with variable temperature of 200 °C, 300 °C and ambient conditions. SEM/EDS and XRD techniques were used to examine the worn samples and to identify the formation of new phases during wear test. The wear characteristics pertaining to wear rate, volume loss, and COF were computed. The coating exhibits both intermetallic phases, such as Mo2C and Co3W3C, and challenging stages, such as Cr3C2, Ni3C, W2C, Fe2C, and SiC. There has been a resultant improvement in wear resistance and hardness of coating relative to the base alloy.

Keywords

• FeNiCrMo (Metco 41C)
• WC-Co
• Boiler steel
• HVOF
• Sliding wear