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The NiTi claddings by tungsten inert gas (TIG) with Ni and Cu interlayer were manufactured to resist the cavitation erosion-corrosion (CEC). The cavitation test, the open circuit potential and the potentiodynamic polarization measurements were used to study the synergistic effect among cavitation erosion (CE) and corrosion for the NiTi claddings. After the CEC test for 11h, the cumulative mass loss of 304 stainless steel is 5 and 1.15 times that of NiTi-Ni-TIG cladding and NiTi-Cu-TIG cladding, respectively. In NiTi-Cu-TIG cladding, the galvanic corrosion between the Cu-Ti intermetallics and the B2 phase causes the anodic dissolution of the Cu-Ti intermetallics, and results in the B2 phase losing support and spalling off during the CEC test. In contrast, NiTi-Ni-TIG cladding can be used against the CEC because of its uniform microstructure, no Cu-rich area and the effect of corrosion on CE of NiTi-Ni-TIG cladding is small.

In this study, Ni-Al₂O₃-based composite clads on SS-316 substrates using a microwave irradiation method have been developed. Microwave-processed clads were characterized using various nondestructive techniques to investigate microstructure, phase analysis, porosity assessment and measurement of microhardness. The findings of the microstructural analysis demonstrated the formation of solid, metallurgically bonded and defect-free clads with a thickness of approximately 970$\mu$m. X-ray diffraction (XRD) phase analysis study confirmed the existence of hard and intermetallic phases in the clad region. Composite clad region exhibited a low porosity value of $\sim$1.3%. The average microhardness of the clad region was 3.63 times that of the substrate region. Further, cavitation erosion (CE) behavior of the developed clads was investigated using vibration CE test rig under various stand-off distances and immersion depths. CE results showed that the composite clads exhibited 6.9 times better erosion resistance than SS-316 substrate. CE resistance increased with an increase in stand-off distance and the depth of immersion.

Mg alloys are ultralight but their structural applications are often limited by their poor wear and corrosion resistance. The research aimed to address the problem by laser-cladding. Cladding with SiC powder onto surface of AZ91D was carried out using Nd:YAG laser. The laser-clad surface was analyzed using the optical microscope, SEM equipped with EDS, and XRD and found to contain SiC and other Si compounds such as Mg₂Si and Al_3.21Si_0.47 as well as much refined α-Mg grains and β-Mg₁₇Al₁₂ intermetallics. The laser-clad surface possesses considerably higher hardness but its corrosion resistance is not improved, indicating that the laser-cladding technique can only be adopted for applications in noncorrosive environments where wear is the predominant problem.

With the rapid advancement of modern society, the applications of materials are expanding across various fields. Among these, metallic materials have found wide use in industries such as biomedical, petrochemical, aerospace, orbital bridges, and marine vessels, making significant contributions to the manufacturing sector of the economy. As heavy machinery in industries undergoes rapid updates and iterations, there is a growing demand for metal fittings and structural components. However, these metal materials often experience common forms of failures, such as corrosion and wear, particularly at the surface, highlighting the crucial importance of surface protection. Material surface engineering presents a viable solution that effectively balances internal performance and investment costs, specifically addressing issues related to surface degradation and repair. By controlling the surface composition and structural design, it becomes possible to manage friction, corrosion, and mechanical properties of metal materials, resulting in notable advancements. One notable technique that has gained considerable traction in automotive engineering, aerospace, and other industries is tungsten inert gas (TIG) cladding. This technique offers unique composition properties, a pollution-free coating process, and a strong metallurgical bond between the alloy coating and the substrate. This review aims to provide a concise overview of TIG cladding, discussing parameter selection and the impact of different cladding powders on coating characteristics. Additionally, it summarizes the recent applications and research status of TIG cladding on titanium alloys, stainless steels, and other nonferrous alloys concerning their wear resistance, mechanical properties, and corrosion resistance. By exploring the advancements and findings in these areas, this review aims to contribute to the body of knowledge in the field of surface engineering and facilitate further research and development in TIG cladding technology.

A TiNiCoCrVSi high entropy alloy (HEA) coating was prepared on Ti–6Al–4V alloy by laser cladding. Then, the microstructure, phase composition, hardness, wear resistance and high-temperature oxidation resistance of the prepared coatings were investigated. The wear behavior of the TiNiCoCrVSi coating against a Si₃N₄ ball was evaluated under dry sliding conditions. The high-temperature oxidation resistance was tested at 800^∘C. The results show that the phase structure of the TiNiCoCrVSi coating was mainly composed of a body-centered cubic (BCC) (Ni,Co)Ti₂ and (Ti,V)₅Si₃. The TiNiCoCrVSi coating has a high hardness, and the highest surface hardness was 1357 HV. The wear volume of the coating was 1/7 of that of Ti–6Al–4V. The wear mechanism was abrasive wear and oxidative wear. The TiNiCoCrVSi coating exhibited good high-temperature oxidation resistance at 800^∘C. A dense oxide film (TiO₂, Cr₂O₃ and NiCr₂O₄) was formed on the surface of the coating. The dense oxide film prevented oxidation. The high-temperature oxidation resistance of the coating was 1/12 of that of the substrate.