In present work the Cr₃C₂–NiCr coating was deposited on magnesium alloy substrate with high velocity oxygen fuel (HVOF) spraying. The microstructure of the samples has been characterized by means of electron microscopy, SEM and phase composition analysis carried out. The porosity of coatings has been also estimated. Finally, tests of selected mechanical properties, such as instrumented indentation, abrasive erosion have been performed. The results of the investigations confirmed that dense, homogeneous and well-adhered Cr₃C₂–NiCr cermet coating is possible to obtain onto the magnesium AZ31 alloy substrate. Moreover, the coatings exhibit high resistance to erosion.

In this paper, three commercial cermet powders, WC-Co-Cr, WC-Co and WC-Cr₃C₂-Ni, were sprayed by the High Velocity Oxy Fuel (HVOF) method onto magnesium alloy AZ31 substrate. The coatings were investigated in terms of their microstructure, phase analysis and residual stress. The manufactured coatings were analyzed extensively using optical microscopy (OM), X-ray diffraction (XRD), scanning (SEM) and transmission electron microscopy (TEM). Based on microstructure studies, it was noted that the coatings show satisfactory homogeneity. XRD analysis shows that in WC-Co, WC-Co-Cr and WC-Cr₃C₂-Ni coatings, main peaks are related to WC. Weaker peaks such as W₂C, Co_0.9W_0.1, Co and W for WC-Co and W₂C, Cr₃C₂ and Cr₇C₃ for WC-Cr₃C₂-Ni also occur. In all cermet coatings, linear stress showed compressive nature. In WC-Co and WC-Cr₃C₂-Ni, residual stress had a similar value, while in WC-Co-Cr, linear stress was lower. It was also proved that spraying onto magnesium substrate causes shear stress in the WC phase, most likely due to the low elastic modulus of magnesium alloy substrate.

In the present study, two different cermet coatings, WC–CrC–Ni and Cr₃C₂–NiCr, manufactured by the high-velocity oxy-fuel (HVOF) method were studied. They are labeled as follows: WC–CrC–Ni coating—WC and Cr₃C₂–NiCr coating—CrC. These coatings were deposited onto a magnesium alloy (AZ31) substrate. The goal of the study was to compare these two types of cermet coating, which were investigated in terms of microstructure features and selected mechanical properties, such as hardness, instrumented indentation, fracture toughness, and wear resistance. The results reveal that the WC content influenced the hardness and Young’s modulus. The most noticeable effect of WC addition was observed for the wear resistance. WC coatings had a wear intensity value that was almost two times lower, equal to 6.5·10⁻⁶ mm³/N·m, whereas for CrC ones it was equal to 12.6·10⁻⁶ mm³/N·m. On the other hand, the WC coating exhibited a lower value of fracture toughness.

Magnesium alloys are very interesting engineering materials due to their very high strength to density ratio (the best among metallic alloys). However, because of low hardness as well as low resistance against erosion, abrasion and corrosion, their applications in the industry is very limited....

This paper presents the effects of laser treatment (fiber laser YLS-4000) on the microstructure and selected mechanical properties of the surface layer of AlMg (AlMg9) foundry alloy obtained by alloying with boron carbide (B₄C). The correlation between laser alloying process parameters and selected properties of the formed layer was discussed. The studies were supported by microstructural analysis of the remelted zone (RZ), heat affected zone (HAZ), undissolved carbide particles, substrate material, and precipitates formed during rapid solidification. Metallographic investigations of the laser-treated layer were performed using optical microscopy and scanning electron microscopy (SEM). The elemental composition and a detailed analysis of chemical composition in micro-areas were carried out using energy dispersive X-ray spectroscopy (EDS). The remelting thickness, heat-affected zone (HAZ), and amount of base material in surface layers were determined. Microhardness tests were performed on transverse cross-sections of the remelted zone to obtain the hardness profiles in the base material (BM), remelted zone (RZ), and heat affected zone (HAZ). The hardness, roughness, and wear resistance measurements showed that the highest tribological properties of the obtained surface layer were achieved using 0.5 Bar protective gas (Ar) during alloying with B₄C powder.