Composition, Structure and Electrical Resistivity of ZnO1-x Films Deposited by RF Magnetron Sputtering under Various O2/Ar Gas Ratios

ZnO1-x thin films were deposited by RF magnetron sputtering on conducting silicon wafers at room temperature with ZnOn (n≤1) target under an atmosphere of O2/Ar ratio varying from 0 to 2.0. The correlation between composition, structure and electrical resistivity of the obtained films was investigated. X-ray diffraction analysis revealed that the prepared würtzite ZnO1-x films had c-axis preferential growth orientation. When the O2/Ar ratio was lower than 0.5, the main form of defects in the films was oxygen vacancy; when it was 0.5, the composition of the film approached to the stoichiometric ZnO and had the least number of defects; after that, the main type of defects in the films was interstitial zinc. Thus, with increasing O2/Ar ratio, the electrical resistivity of the films increased first and then decreased.

Compositional, Structural and Mechanical Properties of (Ti,Cr,Al)N Coatings Deposited on the Surface of Piston Rings

A novel super hard coating system of (Ti,Cr,Al)N was synthesized by multi arc ion plating technology. The Metallic ratio of Cr, Ti, and Al was varied by adjusting the currents of different TiAl target. The CrTiAlN composite coatings with different chemical composition were deposited on the surface of 65Mn steels by multi-ion plating technology in a gas mixture of Ar+N2. The coatings were characterized by means of energy dispersive X-ray(EDX) analysis, X-ray diffractmetry(XRD), scanning electronic microscopy(SEM), microhardness tester respectively. The experimental results show that the deposition velocity of CrTiAlN coatings reached maximum value, about 72nm/min. And the surface morphology of CrAlTiN films are compact and dense. The main composition of CrTiAlN composite films is Cr、Ti、Al、N, with the mass percent of Cr 29.61%,Ti 21.42%,Al 14.88%,N 34.10%. And the cross-section morphology appears as fibrous columnar crystals structure. Compared with CrN coatings, the preferential growth orientation of CrAlTiN films was changed from CrN (111) to CrN (200) after the addition of Ti, Al element. When the TiAl target arc current was 50A, the hardness reached the maximum value, 35GPa.

Investigation on the Properties of Sb-Doped CdTe Thin Films

Pure CdTe thin films and metal Sb-doped CdTe thin films are prepared on soda lime glass substrates by vacuum evaporation method. The prepared films have a cubic crystal structure with a preferential growth orientation along CdTe (111) crystal orientation. The experimental results show that the film surface doped Sb is more compact and uniform. And doping Sb in pure CdTe thin films significantly enhance the optical absorption and reduce the width of the band gap, which means that the optical absorption range of CdTe thin films can be widened. Finally, on the aspect of electrical properties, the resistivity of the thin films has significantly been lower.

Anisotropy Affecting Dendrite Growth of Fe-C Alloy in a Forced Flow

The phase-field model coupling with the concentration field and flow field was used to simulate the dendrite growth during isothermal solidification of Fe-C alloy in a forced flow. The effects of anisotropy modulus and anisotropy strength on the dendrite growth are studied. The results indicate that the dendrites have four preferential growth orientation and the side-branches growth is not perpendicular to the primary branch while the dendrite along with crystallographic directions. When the dendrite along with crystallographic directions, the dendrites have six preferential growth orientation and the side-branches are parallel to the neighborly primary branch. At a anisotropy strength of 0.01, the crystal have no apparent principal branch and grows into coral shapes.With an increase in anisotropy strength, the tip solute concentration decreases, makes the dendrite growth become fast, the tip velocity increased continuously.

Effects of Al Content on the Microstructures and Oxidation Resistance of Cr1-xAlxN Films Synthesized by Multi-Arc Ion Plating Method

The CrAlN composite coatings with different Al content are deposited on 65Mn steel substrate by multi-ion plating technology. The structure, surface morphology, composition and oxidation resistance of CrAlN composite coatings are tested by XRD, EDS, SEM and oxidation furnace, respectively. The experimental results show that the preferential growth orientation of the coatings was changed from CrN (111) to CrN (200) after the addition of Al element. And the surface roughness of CrAlN coatings increase gradually with increasing of Al content. Compared with CrN coatings, the CrAlN composite coatings show much better oxidation resistance. And the oxidation resistance ability will enhance with increasing Al content, because Al and Cr oxide form after oxidation in high temperature condition which could reduce the diffusivity ability of oxygen.

Microstructure of CrN-Based Nano Composite Solid Lubrication Films

The complex plating-sulfurizing process which fitted magnetron sputtering together with low temperature ion sulfurizing, was utilized to prepare a new CrN-based nano composite solid lubrication films with different Mo content. The structure, surface morphology, composition, and valence states of CrMoN composite coatings are tested by XRD, EDS, SEM and XPS respectively. The SEM results showed that the roughness of CrN composite coating reduces with addition of Mo element. X-ray diffraction pattern indicated that the preferential growth orientation of the coatings is changed from CrN (111) to CrN (220) after the addition of Mo element, the diffraction peaks shift leftwards as Mo content increasing, and the majority of phases are Mo2N and CrN, besides which MoS2 and Cr2S3 were created.