Wear behavior of gas tunnel type plasma sprayed Zr-based metallic glass composite coatings

Gas tunnel type plasma spraying is a prospective method to produce metallic glass composite coatings with high quality due to its noteworthy feature of process controllability. In this study, Zr55Cu30Al10Ni5 metallic glass composite coatings were produced by gas tunnel type plasma spraying torch under optimum spraying conditions with selected plasma currents. The formation mechanism, sliding, and erosive wear behaviors of the coatings with respect to plasma current was examined. The phase and thermal analyses as well as microstructure of the plasma sprayed coatings produced at different plasma currents were characterized using X-ray diffraction (XRD), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and energy dispersive X-ray spectroscopy (EDX) techniques. The sliding and erosive wear behaviors of the coatings were studied using a pin-on-disc and a specially designed erosive wear tester, respectively. The results showed that an increase in plasma current increased the crystalline content in the metallic glass composite coatings, which enhanced the hardness and wear resistance of the coatings.