Friction and Wear Behaviors of Ti/Cu/N Coatings on Titanium Alloy Surface by DC Magnetron Sputtering

Ti/Cu/N coatings with different Cu contents were deposited on titanium alloy surface by the DC magnetron sputtering technique.XPS and FESEM were employed to characterize the composition and structure of the coating on the Ti6A14 V substrates.In addition,The adhesion force,friction,and wear properties of the Ti/Cu/N coatings were investigated.The experimental results showed that the coarse particles of the coatings would grow more and the surface roughness increased with the increase of copper content in the coatings;The coatings showed a strong adhesion force;The friction coefficient of the coating of the samples was less than the substrate,reaching 0.19 at least.The wear resistance of the coatings could be improved by optimizing and controlling the relative content of Ti,Cu,N elements on the titanium alloy surface,especially the 10.98 at%contents of the copper.The sample C2 kept the best wear resistance.

Investigation on plasma-sprayed ZrO_2 thermal barrier coating on nickel alloy substrate

The thermal barrier coatings with NiCrAlY alloy bonding layer, NiCrAlY Y 2O 3 stabilized ZrO 2 transition layer and Y 2O 3 stabilized ZrO 2 ceramic layer are prepared on nickel alloy substrates using the plasma spray technique. The relationship among the composition, structure and property of the coatings are investiga ted by means of optical microscope, scanning electronic microscope and the experiments of thermal shock resistance cycling and high temperature oxidation resistance. The results show that the structure design of introdu cing a transition layer between Ni alloy substrate and ZrO 2 ceramic coating guarantees the high quality and properties of the coatings; ZrO 2 coatings doped with a little SiO 2 possesses better thermal shock resistance and more excellent hot corrosion resistance as compared with ZrO 2 coating materials without SiO 2 ;the improvement in performance of ZrO 2 coating doped with SiO 2 is due to forming more dense coating structure by self closing effects of the flaws and pores in the ZrO 2 coatings.

Microstructure and Properties of ZL101 Alloy Affected by Substrate Movement Speed of a Novel Semisolid Continuous Micro Fused-Casting for Metal Process

A novel semisolid continuous Micro Fused-Casting additive manufacturing technology for producing a ZL101 alloy strip was developed, Micro Fused-Casting means that the semisolid metal slurry was pressed out from the outlet of bottom of crucible to the movable plate. The degree of sub-cooling was easily provided by movement of substrate in the micro fused-casting area. Under the aid of 3 D manufacturing software, the ZL101 alloy strip was solidified and formed layer by layer. The microstructure and properties of ZL101 semisolid slurry were improved by the cooling conditions. The results showed that the ZL101 alloy strip samples fabricated by Micro Fused-Casting had uniform structures and good performances with the substrate movement speed at 20 mm/s and the temperature at 590 ℃, the ultimate tensile strength and elongation of the ZL101 alloy strip reached 242.59 MPa and 7.71%, while the average Vickers hardness was 82.55 HV.

Effect of Sr on Grain Refinement of Mg–3%Al Alloy Containing Trace Fe by Carbon-Inoculation

Magnesium（Mg）-3% aluminum（Al）（in weight） alloy was modified by carbon（C） inoculation combining with strontium（Sr）.The effects of trace 0.1% iron（Fe） addition and operating sequence of carboninoculation and Fe addition on the grain size of Mg-3%Al alloy were studied.The results reveal that the Sr addition could effectively suppress grain-coarsening resulted from the inclusion of Fe in the carboninoculated Mg-Al alloy.Sr addition could contribute to the formation of the duplex-phase particles that Al-C-rich phases coated on Al-Fe or Al-C-Fe-rich phases,regardless of the Fe addition sequence.These duplex-phase particles should be the potent substrates for α-Mg grains.Consequently,Sr addition could effectively subsidize the inhibiting effect of Fe on grain refinement and the active nuclei were maintained.In other words,Sr plays a counter role in the poisoning effect of Fe on the microstructure of Mg-3%Al alloy.