This study reveals the effect of TiB₂ particles on the mechanical and tribological properties of Fe₃Al-TiB₂ composite coatings against an alumina counterpart. The feedstock was produced by milling Fe₃Al and TiB₂ powders in a high energy ball mill. The high-velocity oxy-fuel (HVOF) technique was used to deposit the feedstock powder on a steel substrate. The effect of TiB₂ addition on mechanical properties and dry sliding wear rates of the coatings at sliding speeds ranging from 0.04 to 0.8 m·s-1 and loads of 3, 5 and 7 N was studied. Coatings made from unreinforced Fe₃Al exhibited a relatively high wear rate. The Vickers hardness, elastic modulus and wear resistance of the coatings increased with increasing TiB₂ content in the Fe₃Al matrix. The wear mechanisms strongly depended on the sliding speed and the presence of TiB₂ particles but were less dependent on the applied load.
Keywords: HVOF; dry sliding wear; high-velocity oxy-fuel; iron aluminide; mechanical properties; titanium diboride.