Effect of Laser Remelting of Fe-Based Thermally Sprayed Coating on AZ91 Magnesium Alloy on Its Structural and Tribological Properties

An Fe-based coating was thermally sprayed onto the surface of AZ91 magnesium alloy via High-Velocity-Oxygen-Fuel (HVOF) method. The with a thickness 530 ± 25 µm and porosity 0.7 0.1% did not show any macrostructural defects cause degradation alloy. Laser remelting layer resulted in recrystallization structure disappearance presented pores, splat boundaries, other defects. This led to an increase hardness remelted from original 535 20 HV0.3 up 625 5 HV0.3. However, during laser at power 1000 W, stress cracking occurred. tribological properties were evaluated by ball-on-plate method under dry conditions. Compared uncoated alloy, higher value friction coefficient (COF) measured for as-sprayed coating. there decrease wear rate weight loss. further Based on obtained data, it has been shown that application laser-remelted coatings Mg improves compared bare coatings.