Microstructure and friction-wear performances of laser-cladded nano-CeO₂–reinforced NiCoCrAlY coatings at high temperature

Abstract

Nano-CeO2–reinforced NiCoCrAlY coatings were fabricated on Ti6Al4V alloy using laser cladding. The morphologies, chemical compositions, and phases of obtained coatings were analyzed using a scanning electron microscope, energy-dispersive spectrometer, and X-ray diffraction, respectively, and the effects of nano-CeO2 mass fraction on the coefficient of friction and the wear rate of NiCoCrAlY coating at 600 °C were investigated using a ball-on-disk wear test. The results show that the nano-CeO2–reinforced NiCoCrAlY coating is mainly composed of NiTi2, Ti3O, CoO, and β-Ti phases, while the new phases of AlTi3 and (Ni, Co)2Ti4O are formed after the wear test. The average coefficients of friction of NiCoCrAlY coatings with the nano-CeO2 mass fractions of 0%, 2%, 4%, and 6% are 0.699, 0.655, 0.636, and 0.615, respectively, and the corresponding wear rates are 4.04 × 10−7, 3.95 × 10−7, 3.13 × 10−7, and 2.35 × 10−7 mm3 N−1 m−1, respectively, which decrease with the increase of nano-CeO2 mass fraction. The wear mechanism is primary adhesive wear and oxidation wear, accompanied by slight abrasive wear, and the addition of nano-CeO2 is the main factor that is enhancing wear resistance.

A Review on the Enhancement of Mechanical and Tribological Properties of MCrAlY Coatings Reinforced by Dispersed Micro and Nanoparticles

“…Investigation due to [93] further confirmed the role of oxide chemistry in wear resistance. In this study, the incorporation of CeO 2 reinforcement to the laser-cladded NiCoCrAlY coatings elevated their wear resistance at 600 • C. Examination of worn tracks revealed that more oxides were ejected during the experiments with unmodified coatings, which led to scratching the coating and caused abrasive wear.…”

“…Not only did the formation of tribo-films promote the antifriction effect, but it also increased the microhardness and reduced the cutting effect associated with the abrasive wear. Investigation due to [93] further confirmed the role of oxide chemistry in wear resistance. In this study, the incorporation of CeO2 reinforcement to the laser-cladded NiCoCrAlY coatings elevated their wear resistance at 600 °C.…”

“…Jiaxing et al [93] studied the effects of CeO 2 addition on the formation and microstructure of the final NiCoCrAlY coating. They noted that CeO 2 could increase the fluidity of the molten pool and its heat transfer, thereby forming a microserrated type bonding of coating with the substrate with enhanced bond strength and reduced crack sensitivity.…”

Multi-objective optimization of WC-12Co coating by high-velocity oxygen fuel spray using multiple regression-based weighted signal-to-noise ratio

“…With HVOF spray, the powder feed rate, spray distance, and oxygen/propane ratio are the critical parameters that predominantly affect the quality of the deposited coating. 9,20,21…”

Effect of Ti2SnC mass fraction on microstructure and friction–wear performance of laser cladded Ni–WC coatings under WS2 lubrication condition

“…4 At present, laser cladding (LC) has been widely used in the hardness improvement of plastic forming molds due to its low dilution rate, high hardness, and wear resistance. 5 Among many alloy powders, Ni-based powder with good self-melting characteristic is widely applied for laser cladding (LC), [6][7][8] however, it can not meet the higher requirements of plastic forming molds. As a kind of ceramic, WC is usually used to reinforce the Ni-based coating, which is because the WC with high hardness can form composite with the Ni-based coating.…”