Tribological behavior of Fe-based bulk metallic glass

The unlubricated tribological characteristics of coating layers containing an Fe-based amorphous matrix have been investigated in air using an alumina ball with a diameter of 3.1 mm. From the ball-on-disk test system, the friction coefficient could be measured for up to 3,000 seconds. The temperature changes on the worn surfaces were also simultaneously measured using an infrared thermometer. Three different types of coating layers having an Fe-based amorphous matrix, an Fe-based amorphous matrix with embedded Ni-based self-fluxing alloy particles, and an Fe-based amorphous matrix with embedded WC particles were prepared through a high velocity oxy-fuel (HVOF) process. Although the coating layers have certain levels of porosity, unique frictional characteristics attributed to the amorphous matrix were observed during the friction tests. Compared with conventional bearing steels such as AISI 521000 (Hv=840), excellent tribological and wear characteristics were obtained, demonstrating that an Fe-based bulk metallic glass powder is a viable engineering material for practical anti-wear coating applications.