Pure aluminum oxide (Al₂O₃), ZrO₂ toughened Al₂O₃ (ZTA; 25–30% ZrO₂), and ZTA (55–60% ZrO₂) ceramic particles reinforced Cr25 matrix composites are successfully fabricated by the infiltration casting process. The volume fraction of ceramic particles in the composites is 47–55%. The interface structure between ceramic particles and the matrix was analyzed by digital probing microscopy and was found to be continuous mechanical bonding. The wear behavior of the composites was studied by a three-body abrasive wear tester. ZTA (55–60% ZrO₂) reinforced Cr25 composite has excellent wear resistance which is approximately six times higher than that of the high chromium cast iron matrix. It is discovered that the wear mechanism of composites is micro-cutting and fatigue stripping. A correlation exists between the wear resistance of composites and the strength of ceramic particles.

Using zirconia toughened alumina (ZTA) particles and Ni–Ti complex powders as raw materials, high-Cr cast iron reinforced by ZTA particles was prepared by an infiltration casting process. A continuous transition layer formed at the interface between ZTA particles and the Cr15 matrix, which proves that there is strong metallurgical interfacial bonding at the interface. The phases in the Ni–Ti layer of the ZTA_P/Fe composite were preserved compared with the microstructure of sintered ZTA ceramic preform. The hardness of the Ni₃Ti, TiO and AlNi₂Ti phases in the interfacial transition layer was measured by the nano-indentation method, which is 12.5 GPa, 16.1 GPa and 9.2 GPa, respectively. The three-body wear resistance of the composite reached 12.6 times that of high-Cr cast iron.

In this paper, the electronic, mechanical and thermodynamic properties of AlNi₂Ti are studied by first-principles calculations in order to reveal the influence of AlNi₂Ti as an interfacial phase on ZTA (zirconia toughened alumina)/Fe. The results show that AlNi₂Ti has relatively high mechanical properties, which will benefit the impact or wear resistance of the ZTA/Fe composite. The values of bulk, shear and Young’s modulus are 164.2, 63.2 and 168.1 GPa respectively, and the hardness of AlNi₂Ti (4.4 GPa) is comparable to common ferrous materials. The intrinsic ductile nature and strong metallic bonding character of AlNi₂Ti are confirmed by B/G and Poisson’s ratio. AlNi₂Ti shows isotropy bulk modulus and anisotropic elasticity in different crystallographic directions. At room temperature, the linear thermal expansion coefficient (LTEC) of AlNi₂Ti estimated by quasi-harmonic approximation (QHA) based on Debye model is 10.6 × 10⁻⁶ K⁻¹, close to LTECs of zirconia toughened alumina and iron. Therefore, the thermal matching of ZTA/Fe composite with AlNi₂Ti interfacial phase can be improved. Other thermodynamic properties including Debye temperature, sound velocity, thermal conductivity and heat capacity, as well as electronic properties, are also calculated.

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 (i_corr) 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 (i_corr) 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.