Preparation of Zr-based amorphous composite coatings on TA2 surface and their resistance to extreme corrosion and wear

In this paper, Zr-based amorphous coatings (Zr-coating) were prepared on TA2 substrate by plasma spraying technique. By employing a combination of coating tensile testing, electrochemical corrosion, friction and wear tests, molecular dynamics (MD), and density functional theory (DFT) calculations, the interfacial bonding strength, tribological properties, and corrosion resistance of the corrosion- and wear-resistant coatings were analyzed. The results show that: The organization of Zr-coating is uniform and dense without cracks, pores and other defects, and the thickness is about 227.07 mu m. The bond strength of Zr-coating on TA2 substrate reaches 17.2 MPa, and the hardness is 550 Hv. The corrosion rate of Zr-coating in 20 % HNO3 solution is 0.0093 mm/a. The protection efficiency for TA2 substrate is 94.35 %. Zr41.2Ti13.8Cu12.5Ni10Be22.5(100)crystal surface of the value of the function of the work of the maximum 3.467 eV, Zr-coating the more difficult for electrons to escape, corrosion resistance is better compared to TA2. The diffusion coefficient of oxygen atoms in the ZrO2 passivation film (6 x 10- 8) was larger than that in the TiO2 passivation film (1.6667 x 10-9). In addition, Zr-coating has a lower wear rate (3.19 x 10- 7mm3N-1mm- 1) compared to TA2, which is mainly dominated by fatigue wear and oxidative wear. This study provides a theoretical basis for an in-depth analysis of the corrosion and wear mechanisms of Zr-based amorphous coatings in dilute nitric acid solutions, and provides meaningful guidance for the design of new corrosion and wear-resistant coatings for use.