Jae-In Jeong

Properties of TiN Films Fabricated by Oblique Angle Deposition

Oblique angle deposition (OAD) is a physical vapor deposition where incident vapor flux arrives at non-normal angles. It has been known that tilting the substrate changes the properties of the film, which is thought to be a result of morphological change of the film. In this study, OAD has been applied to prepare single and multilayer TiN films by cathodic arc deposition. TiN films have been deposited on cold-rolled steel sheets and stainless steel sheet. The deposition angle as well as substrate temperature and substrate bias was changed to investigate their effects on the properties of TiN films. TiN films were analyzed by color difference meter, scanning electron microscopy, nanoindenter and x-ray diffraction. The color of TiN films was not much changed according to the deposition conditions. The slanted and zigzag structures were observed from the single and multilayer films. The relation between substrate tilting angle () and the growth column angle () followed the equation of

Mechanical Properties of TiAlSiN films Coated by Hybrid Process

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Effect of Heat Treatment on the Corrosion Resistance of the Al-Mg Coated Steel Sheet

System Solution Research Center, Research Institute of Industrial Science & Technology, Pohang City, Gyeong-buk 790-330, Korea(Received August 5, 2014 ; revised August 19, 2014 ; accepted August 25, 2014)AbstractIn this study, TiAlSiN coatings have been successfully synthesized on stainless steel and tungsten carbidesubstrate by a hybrid coating method employing a cathodic arc and a magnetron sputtering source. TiAland Si target were vaporized with the cathodic arc source and the magnetron sputtering source, respectively.Process gas was the mixture of nitrogen and argon gas. With the increase of Si content, the crystallinityand the grain size of TiAlSiN film was decreased. At the Si content of more than 8 at.%, grain size ofTiAlSiN was saturated at around 2 nm. The hardness value of the TiAlSiN film increased with incorporationof Si, and had the maximum value of ~ 3,233 Hv at the Si content of 9.2 at.%. The oxidation resistanceof TiAlSiN film was enhanced with the increase of Si content.

Characteristics of Al Films Prepared by Oblique Angle Deposition

Double layer films which consisted of aluminum(Al) and magnesium(Mg) have been prepared by e-beam deposition. The structure, alloy phase, and corrosion resistance of the prepared films were investigated before and after heat treatment. The first (bottom) layer fixed with Al, and the thickness ratio between Al and Mg layers has been changed from 1 : 1 to 5 : 1, respectively. Total thickness of Al-Mg film was fixed at 3 μm. The cold-rolled steel sheet was used as a substrate. Heat treatment was fulfilled in an nitrogen atmosphere at the temperature of 400oC for 2, 3 and 10 min. Surface morphology of as-deposited Al-Mg film having Mg top layer showed plate-like structure. The morphology was not changed even after heat treatment. However, cross-sectional morphology of Al-Mg films was drastically changed after heat treatment, especially for the samples heat treated for 10 min. The morphology of as-deposited films showed columnar structure, while featureless structure of the films appeared after heat treatment. The x-ray diffraction data for as-deposited Al-Mg films showed only pure Al and Mg peaks. However, Al-Mg alloy peaks such as Al3Mg2 and Al12Mg17 appeared after heat treatment of the films. It is believed that the formation of Al-Mg alloy phase affected the structure change of Al-Mg film. It was found that the corrosion resistance of Al-Mg film was increased after heat treatment.

Properties of AlTiN Films Deposited by Cathodic Arc Deposition

Oblique angle deposition (OAD) is a physical vapor deposition method which utilizes non-normal angles between the substrate and the vaporizing source. It has been known that tilting the substrate changes the properties of the film deposited on it, which was thought to be a result of morphological change of the film. In this study, OAD has been applied to prepare single and multilayer Al films by magnetron sputtering. The magnetron sputtering source of 4 inch diameter was used to deposit the films. Al films have been deposited on Si wafers and cold-rolled steel sheets. The multilayer films were prepared by changing the tilting angle upside down at each layer interval, which means that when the first layer was deposited at an angle of , the second layer was deposited at an angle of , and vice versa. The microstructure, surface roughness and reflectance of the films were investigated using a scanning electron microscope, a surface profiler and a spectrophotometer, respectively. The corrosion resistance was measured and compared using the salt spray test. The single layer film prepared at an oblique angle of prepared at other angles. However, for the multilayer films, the film prepared at an oblique angle of showed the most compact and featureless structure. The multilayer films were found to exhibit higher corrosion resistance than the single layer films.

Hard coating layer and method for forming the same

The properties of AlTiN films by a cathodic arc deposition process have been studied. Oblique angle deposition has been applied to deposit AlTiN films. AlTiN films have been deposited on stainless steel (SUS304) and cemented carbide (WC) at a substrate temperature of 500oC. AlTiN films were analyzed by scanning electron microscopy, glow-discharge light spectroscopy, micro-vickers hardness, and nanoindenter. When applying a current of 50 A to the cathodic arc source, it showed that the density of macroparticle of AlTiN films was 5 lower than other deposition conditions. With the increase of the bias voltage applied to the substrate up to –150 V, the density of macroparticle was decreased. The change of the N2 flow rate during coating process made no influence on the film properties. For the multi-layered films, the film prepared at oblique angle of 60° showed the highest hardness of 28 GPa and H3/E2 index of 0.18. AlTiN films have been shown a good oxidation resistance up to 800oC.