Electrochemical methods were employed to investigate galvanic corrosion behaviors of super13Cr and P110 couples in NaCl solution at different temperature. Corrosion morphologies and products of the couples were analyzed by SEM, EDS and XRD. The results showed that there were potential difference distinctly between super 13Cr and P110 steel in NaCl solution at different temperature, when its contacted, galvanic corrosion of super 13Cr-P110 steel couples will occurred. P110 was accelerated to corrode as anode and super 13Cr was protected as cathode in the coupling. Super 13Cr-P110 steel couples could not be used as P110 without any protection in NaCl solution at 20 °C to 80 °C. Corrosion current density and galvanic corrosion of super13Cr-P110 steel couples increased with increasing temperature in NaCl solution, of which corrosion products are Fe3O4.

Using as high strength and corrosion resistance of tubing material, the wear properties of TC4 alloy and P110 tubing steel were comparatively studied, the differences and similarities were analyzed that are weight loss of wear rate and friction coefficient and topography of wear mark, the wear mechanism was discussed. The results showed that the topography of TC4 alloy and P110 tubing steel are different entirely, TC4 alloy is furrow, P110 tubing steel is wear pit, the wear resistance of P110 tubing steel is excelled obviously than TC4 alloy, the wear mechanism of TC4 alloy is delamination wear and adhesive wear and fatigue wear. The wear mechanism of P110 tubing steel is delamination wear and abrasive wear.

Effects of pH value on the stress corrosion cracking (SCC) of super 13Cr tubing steel were investigated in 3.5% NaCl solution, that mechanics properties and fracture morphology and SCC resistance and stress corrosion cracking susceptibility index (kscc) were analyzed by slow strain rate tensile (SSRT) stress corrosion cracking experiment method and σ-ε curve and SEM. the results Effects of pH value on the stress corrosion cracking (SCC) of super 13Cr tubing steel were investigated in 3.5% NaCl solution, that mechanics properties and fracture morphology and SCC resistance and stress corrosion cracking susceptibility index (kscc) were analyzed by slow strain rate tensile (SSRT) stress corrosion cracking experiment method and σ-ε curve and SEM. the results showed that super 13Cr tubing steel has good properties of resistance stress corrosion cracking in acidic medium, effects of pH value on super13Cr tubing steel resistance stress corrosion was not very obviously in the acidic medium, with pH value decreased, super 13Cr tubing steel tensile strength decreased, elongation rate decreased, fracture area contraction ratio decreased, break time reduced, the tendency of the stress corrosion cracking increased. the stress corrosion cracking susceptibility index kσ and kε were all increasing, that increased degree of kε were obviously than kσ, effects of pH value on the plastic deformation of super 13Cr tubing steel were greater than tensile strength.

In order to improve wear resistance surface on 0Cr18Ni9Ti stainless steel, Cu coating on the 0Cr18Ni9Ti stainless steel substrate was deposited by electroplating technology. The friction and wear properties of 0Cr18Ni9Ti stainless steel substrate and Cu coating were investigated contrastively. The morphologies of the wear scars were analyzed by scanning electron microscope (SEM), energy dispersive X-ray spectrometer (EDS) and scanning probe microscope (SPM), and the wear mechanism was discussed. The results showed that the wear resistance of Cu coatings was significantly improved as compared to that of 0Cr18Ni9Ti stainless steel substrate. The wear scar of 0Cr18Ni9Ti stainless steel substrate showed flaking pit, and its wear mechanism were delamination and abrasive wear. In case of Cu coating, the wear scars showed morphology of plastic deformation caused by adherent copper debris being pressed, and its wear mechanism were delamination and fatigue wear.

Barrier layer was prepared by Micro-arc oxidation(MAO) technique in silicate solution, and cathodic plasma electrolytic deposition (CPED) technique was used to fabricate Al2O3 ceramic coatings on Ti6Al4V alloy in Al(NO3)3(30g/L) and ethanol-aqueous solutions. Surface morphology and elemental of the coatings were investigated by scanning electron microscope (SEM) and energy disperse spectroscopy (EDS). Reaction phenomena were recorded and products of reactions were analyzed by infrared absorption spectrum KBr compression method. Furthermore, mechanisms of different electrolytes were evaluated.