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A composite coating of Ni–W–Ti 2 AlC was fabricated through direct current electrodeposition. The characterization of the composite coatings included analysis using X-ray diffractometry, scanning electron microscope, energy spectrum analysis, Vickers microhardness testing, electrochemical testing, and tribological testing. The findings indicate that the inclusion of Ti 2 AlC alters both the grain size and microstructure of the coatings. The presence of Ti 2 AlC particles facilitates the nucleation process during Ni–W–Ti 2 AlC deposition. The Ti 2 AlC content influences the coating's performance in the bath. Specifically, the microhardness of the Ni–W-(5 g/L) Ti 2 AlC coating exhibits the highest value, experiencing a 41.89 % increase compared to that of the Ni–W coating. Ti 2 AlC contributes to the rectification of defects in the Ni–W–Ti 2 AlC coating. This composite coating exhibits the lowest corrosion current and superior corrosion resistance, particularly with a Ti 2 AlC concentration of 5 g/L. The wear mechanism of the coating encompasses abrasive wear, adhesive wear, and oxidation wear. Notably, the Ni–W–Ti 2 AlC composite coating demonstrates enhanced friction resistance compared to the Ni–W composite coating. Incorporating Ti 2 AlC introduces a novel approach and avenue for fabricating high-performance tungsten-based functional coatings. [ABSTRACT FROM AUTHOR]

A nanocrystalline surface layer was fabricated on the surface of CuCr8 alloy by surface ultrasonic rolling treatment (USRT) with different rolling depth. The surface morphology, microstructure, hardness, surface strength and corrosion resistance were systematically characterized by using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and the corresponding test methods. The results showed that the USRT treatment did not change the surface phase of the CuCr8 alloy, but only refined the surface grain. The rolling depth had great influence on the surface properties of the CuCr8 alloy. When the rolling depth was 0.15 mm, the surface comprehensive performance was the best. The surface grain size was about 78 nm, the surface hardness was up to 120 HV 0.05 , the tensile strength reached to 400 MPa, and the corrosion performance was significantly enhanced. The content of Cr, CuO and Cu(OH) 2 in the passivation film of the USRT treated alloy was higher than that of the CG alloy. The USRT treatment provides a new method for fabricating CuCr alloy vacuum break tubes with high surface properties. • A gradient nanocrystalline surface layer was fabricated on the surface of CuCr8 alloy after USRT. • The surface hardening layer shows better corrosion resistance than the untreated sample. • The rolling depth had great influence on the surface properties. [ABSTRACT FROM AUTHOR]