Mechanical properties investigation of industrial graphene nanoplatelets mixed with WC-12Co deposited by atmospheric plasma spraying

Tungsten carbide cobalt coatings (WC-Co) are widely used in tunnelling excavation tool design due to their superior properties under challenging operational conditions that involve strength, hardness, and wear resistance. Current research studied the addition of graphene-based materials to WC-Co coatings, which has shown enhanced properties and durability of the produced coats. This study involves the introduction of industrial graphene nanoplatelets (GNPs) at different percentages to WC-Co powder and studying its effect on the mechanical and tribological properties of atmospheric plasma-sprayed coatings on high-strength steel. Coatings are characterised using scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis. Mechanical and tribological properties are tested through microhardness, adhesion tests, and Taber abrasion index measurements. The results show the presence of GNP embedded in the coating layer of all the samples with different GNP concentration percentages. The adhesion strength of unmodified coating at room temperature, Taber abrasion index and Rockwell microhardness values are 77.6 MPa, 0.181 and 96.7 HRC respectively. Adding 0.5% industrial GNP shows better results than other concentrations applied with a slight decrease in adhesion strength of 63.8 MPa, a 16% reduction in abrasion index, and an almost unchanged microhardness value of 96 HRC for all samples.