Wear- and corrosion-resistant iron-based amorphous coating in diluted biodiesel medium

Biodiesel is an eco-friendly source of energy that is synthesized from plant- or animal-based oils and fats. However, the commercial use of biodiesel is limited due to its drawbacks such as auto-oxidation and moisture absorption, leading to accelerated corrosion of the metallic parts and degradation of wear resistance. In this work, a novel amorphous metal coating was proposed to promote the wear and corrosion resistance under multigrade diesel engine oil (15W-40) diluted with 7% palm oil-based biodiesel (B30). The coating was performed using laser cladding technique at different scanning speeds (40 and 60 mm/s) and constant laser power 280 W. Microstructure investigation and X-ray diffraction confirmed amorphous structure and crystalline phase (FeCr). It was found that the wear rate was reduced for the coated specimens by about 90% compared with the uncoated samples. The corrosion rates decreased by 54.74% and 69.96% for scanning speeds 40 and 60 mm/s, respectively. Thanks to the reduced microstructural defects such as grain boundaries in the amorphous structure of the coating. These findings showed that amorphous metal coating provides promising solutions to increase the reliability of using biodiesel without the need for corrosion inhibitors, which reduce the combustion efficiency.