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Ceramic particles reinforced iron matrix composites attract considerable interest in the industrial engineering field due to the ceramic's excellent fatigue and wear resistance. ZTA ceramic particle has been regarded as an ideal reinforcement phase. In this study, three-body abrasive wear behaviours and the mechanism of the ZTA/Fe composites and high chromium white cast iron Cr15 standard samples were investigated. The wear resistance of the ZTA/Fe composite was superior to the Cr15 standard sample under SiO2 abrasives. The extruded ZTA could protect the matrix surrounding ZTA ceramic particles. However, ZTA ceramic particles were cut together with the Cr15 matrix under SiC abrasives. The wear mechanism of the composites was a combination of the cutting and fatigue for SiC abrasives. [ABSTRACT FROM AUTHOR]

Oxide ceramic particle-reinforced iron-based composites showed excellent abrasive wear resistance; however, the weak bonding property of the interfacial layer limited the application in harsh severe conditions. The combination of electroless plating (CVD) and multiarc ion plating technologies (PVD) was used to prepare Ni/Cr coatings on the surface of the ZTA ceramics, which effectively improves the interface bonding properties of the ZTAP/Fe composites. The interface of iron matrix composites reinforced by bare ZTA ceramic particles presented visible holes and crevices. After introducing Ni/Cr coating, a continuous and tight transition layer occurred at the interface between the ZTA ceramics and the Cr15 matrix. The diffusion and reaction of Ni and Cr nearby the interface caused a metallurgical bonding of composites. Abrasive wear and slurry erosion behavior of the ZTAP/Fe composites assisted with the metallic coatings was systematically investigated. The results indicated that the transition layer of the composites could effectively resist the removal and corrosion in the slurry fluids. Furthermore, the solid solution of Cr in the iron matrix improved the corrosion resistance of the Cr15 matrix in the artificial seawater medium. The ZTA ceramics and the Cr15 matrix were simultaneously cut under the SiC abrasive during two-body abrasive wear. ZTA ceramic particles play a protective role in the iron matrix due to their high hardness and excellent toughness. [ABSTRACT FROM AUTHOR]

Atmospheric plasma spraying (APS) was taken to fabricate the NiCrAlY coating. The corrosion-wear properties of NiCrAlY coating was measured respectively under deionized water, artificial seawater, NaOH solution and HCl solution. Experimental results presented that the as-sprayed NiCrAlY coating consisted of Ni3Al, nickel-based solid solution, NiAl and Y2O3. In deionized water, the coating with the lowest corrosion current density (icorr) of 7.865 × 10−8 A/cm2 was hard to erode. Meanwhile, it presented a lower friction coefficient and the lowest wear rate. In HCl solution, NiCrAlY coating gave the highest corrosion current density (icorr) of 3.356 × 10−6 A/cm2 and a higher wear rate of 6.36 × 10−6 mm3/Nm. Meanwhile, the emergence of Al(OH)3 on the coating surface could reduce the direct contact between the counter ball and sample effectively, which was conducive to the lowest friction coefficient of 0.24. [ABSTRACT FROM AUTHOR]

NiAl matrix composite coatings were prepared using atmospheric plasma spraying (APS). The mechanical and tribocorrosion properties of the NiAl matrix composite coatings, incorporated with Cr2O3 and Mo, were investigated, and the synergistic effect between corrosion and wear was studied in detail. The microhardness of the composite coating improved from 195.1 to 362.2 HV through the addition of Cr2O3 and Mo. Meanwhile, the Cr2O3 and Mo phases were distributed uniformly in the composite coatings. The X-ray diffraction (XRD) peaks of Ni-based solid solution slightly shifted to the right after adding the Mo. This was probably due to the solid solution of Mo into the matrix. The NiAl–Cr2O3–Mo composite coating had the lowest corrosion current density, wear rate and friction coefficient of 9.487 × 10−6 A/cm2, 3.63 × 10−6 mm3/Nm, and 0.18, in all composite coatings as well as showing excellent tribocorrosion properties. [ABSTRACT FROM AUTHOR]

NiCrAlY and NiCrAlY-Mo coatings were fabricated by atmospheric plasma spraying (APS). The corrosion-wear performance of the coatings was investigated in artificial seawater and the synergistic mechanism between wear and corrosion were evaluated in detail. Results showed that the diffraction peaks of Ni3Al shifted to the right and the microhardness of the coating was improved from 329.8 HV to 342.5 HV with adding the Mo element. Meanwhile, the NiCrAlY-Mo coating had a lower friction coefficient, with a wear rate of 0.26 and 3.69 × 10−6 mm3/Nm, compared to the NiCrAlY coating with a wear rate of 0.37 and 4.67 × 10−6 mm3/Nm. The NiCrAlY coating had severe corrosion and the corrosion mainly occurred in grain boundary. Adding the Mo element, the Mo element was distributed in the grain boundary and the coating had a lower corrosion rate and visibly slighter corrosion. The NiCrAlY-Mo coating had excellent corrosion-wear properties in artificial seawater. [ABSTRACT FROM AUTHOR]