A new method for hard coatings: ABSTM (arc bond sputtering)

Effect of balanced and unbalanced magnetron sputtering processes on the properties of SnO2 thin films

This article presents the application of the response surface methodology for yielding the optimal conditions and for developing robust surface morphologies of zirconium nitride (ZrN) films. In this research, the ZrN films with (Ti, Cr) interfaces ((Ti, Cr)ZrN) were prepared by an unbalanced magnetron (UBM) sputtering. Two kinds of zirconium nitride films, with and without Ti additives, were reported. An orthogonal array for reducing the large number of experiments was introduced. The significant parameters from an analysis of variance for the (Ti, Cr)ZrN films were clearly observed. Furthermore, a quadric model was constructed efficiently. The predicted values and experimental results were close, which confirmed that the quadric model can be effectively used to predict the surface morphologies of the (Ti, Cr)ZrN films in the UBM sputtering. The experimental results were consistent with the response surface predictions. Therefore, it was concluded that the surface morphologies on multilayered films can be accurately predicted by response surface analysis, thereby justifying the reliability and feasibility of the approach.

Oxidation kinetics of sputtered Cr–N hard coatings

Synthesis of (Ti, Zr)N hard coatings by unbalanced magnetron sputtering

Erosion–corrosion wear of Cr/CrN multi-layer coating deposited on AISI-304 stainless steel using the unbalanced magnetron (UBM) sputtering system

Structure and electrochemical characterization of carbon films formed by unbalanced magnetron (UBM) sputtering method

Chromium nitride coatings grown by unbalanced magnetron (UBM) and combined arc/unbalanced magnetron (ABS ™) deposition techniques

Evaluation of fracture toughness of VN hard coatings: Effect of preferred orientation

High temperature oxidation of CrTiAlN hard coatings prepared by unbalanced magnetron sputtering

Superlattice hard PVD coatings exhibit high hardness values up to 60 GPa, wear resistance, and excellent protection against corrosion depending on the choice of the material partners involved. TiAlN/CrN, TiAlN/VN, TiAlYN/VN, TiAlN/ZrN, and CrN/NbN superlattice coatings with typical periods λ of 3–4 nm have been produced economically under production conditions in industrial sized coating equipment. Some of the coatings are characterised by high compressive stresses up to 10 GPa. In such cases the utilisation of the combined cathodic arc/unbalanced magnetron deposition method (arc bond sputtering technology) in combination with the introduction of a lower stressed monolithically grown base layer provides a sufficiently high bonding strength at the interface. The major deposition steps are: (1) pump down and preheating; (2) bombardment of the substrate surface with multi-ionised metal ions generated in a steered cathodic arc discharge; (3) deposition of a base layer (0·1–0·2 μm) using the unbalanced magnetron; (4) deposition of the superlattice coating with simultaneously operated unbalanced magnetrons or a combination of simultaneously operated unbalanced magnetrons and steered cathodic arc sources.

The structure of Cu-Al films prepared by unbalanced DC magnetron sputtering

Cr doped graphite-like carbon (Cr–GLC) graded coating with Cr bottom layer, Cr/C composition gradient layer and Cr–GLC top layer was deposited by unbalanced magnetron co-sputtering of pure chromium and graphite targets. The microstructure, composition and properties including adhesion strength, wear resistance of the as-fabricated Cr–GLC graded coating were investigated by TEM, XPS, scratch test and sliding friction test. Three kinds of phases are detected in the graded layer: pure Cr, a Cr/C nanocrystalline/amorphous phase and amorphous carbon. The HRTEM observation for Cr–GLC top layer with 3 at% Cr indicates that Cr-enriched clusters are embedded in an amorphous carbon matrix. Results of the investigation demonstrate that strong adhesion and stable friction coefficient of the Cr–GLC graded coating are attributed to the consecutive interface microstructure in the coating caused by the interlayer design.

Cubic NaCl-B1 structured multilayer TiAlN/VN with a bi-layer thickness of approximately 3 nm and atomic ratios of (Ti+Al)/V = 0.98 to 1.15 and Ti/V = 0.55 to 0.61 were deposited by unbalanced magnetron sputtering at substrate bias voltages between -75 and -150 V. In this paper, detailed transmission electron microscopy and x-ray diffraction revealed pronounced microstructure changes depending on the bias. At the bias -75 V, TiAlN/VN followed a layer growth model led by a strong (110) texture to form a T-type structure in the Thornton structure model of thin films, which resulted in a rough growth front, dense columnar structure with inter-column voids, and low compressive stress of -3.8 GPa. At higher biases, the coatings showed a typical Type-II structure following the strain energy growth model, characterized by the columnar structure, void-free column boundaries, smooth surface, a predominant (111) texture, and high residual stresses between -8 and -11.5 GPa.

We report the structure, mechanical properties, thermal stability, and durability of Si/SiC/ta-C composite (Si–ta-C) coatings fabricated using simultaneous filtered cathodic vacuum arc deposition and direct current unbalanced magnetron sputtering. Si concentration of 1.25–6.04 at.% was achieved by increasing the unbalanced magnetron sputtering power from 25 to 175 W. Si addition provided functionality to the coating, such as heat resistance, while retaining the high hardness of ta-C coatings. The Si–ta-C coatings were stable up to 600 °C regardless of the Si content, while the coating containing 3.85 at.% Si was stable up to 700 °C. The friction behavior and mechanical properties were dependent on the coating film before and after annealing at 100–200 °C; however, annealing at 300–400 °C decreased disk wear and increased counterpart wear due to an increase in film hardness on account of an endothermic reaction that increased the number of Si–C bonds. This indicates that the basic hardness characteristics of the ta-C coating and the high-temperature structural change of the Si–ta-C coating are important for ensuring high-temperature durability. These characteristics were verified through the low coefficient of friction and wear rate of the 1.25 at.% Si–ta-C coating after annealing at 500 °C.

The side effect of electrosurgery includes tissue charring, smoke generation and the adhesion of tissue to electrodes. These effects prolong surgery and interfere with effective coagulation. In this paper, CrWNx, CrOx and ZrOx coating were prepared by an unbalanced magnetron sputtering. The microstructure of films was characterized using XRD, XPS, TEM and AFM. The hydrophobicity and surface energy of coatings were calculated by contact angle measurement and Wu harmonic mean approach. Anti-sticking in vitro test was performed by monopolar electrosurgery using pork liver tissue. The hardness of CrWNx , ZrOx and CrOx coatings were 44 GPa, 26.3 GPa and 20.7 GPa, respectively. The CrOx coating had the lowest surface energy 33.5 mN/m and the highest contact angle of water as high as 103°. The high surface O-H bonds density of CrOx coating and N-H bonds density of CrWNx coating could explain about their lower polar component of surface energy. All the three PVD coatings remarkably reduced the quantity of tissue adhesion on the electrode from about 2 times (ZrOx and CrWNx coatings) to 4.88 times (CrOx coating) than uncoated SUS304 electrode.