Properties of TiO2 coatings applied by atomic layer deposition (ALD) on 100Cr6 steel

The paper presents the method of forming TiO2 coatings on 100Cr6 steel using the ALD method and assessing the properties of the obtained coatings. The coatings were assessed in terms of surface morphology, chemical composition, contact angle and tribological properties. The performed tribological tests show that TiO2 coatings are characterized by lower resistance to motion. During measuring the geometric structure of surfaces on samples with TiO2 coating, smaller wear traces were recorded than for 100Cr6 steel. The obtained values of the contact angles prove that the 100Cr6 steel coated with TiO2 is more hydrophobic than the uncoated 100Cr6 steel. TiO2 coatings can be used in low-loaded tribological systems and as barrier coatings

Influence of surface roughness on selected properties of the TiAlN coating

The HS6-5-2C steel samples with different surface roughness were used for the tests. After grinding had a roughness parameter of Ra = 0,03 μm, and after polishing Ra = 0,01 μm. A TiAlN coating was applied to the substrate prepared in this way. Using a confocal microscope with an interferometric mode, the geometrical structure of the samples was analyzed. The optical strain gauge was used to measure the contact angle. Tribological tests were carried out in conditions of technically dry friction. The polished sample with the coating was characterized by a more stable course of the friction coefficient, lower wear and a smaller wetting angle

Influence of surface roughness on selected properties of the TiAlN coating

The HS6-5-2C steel samples with different surface roughness were used for the tests. After grinding had a roughness parameter of Ra = 0,03 μm, and after polishing Ra = 0,01 μm. A TiAlN coating was applied to the substrate prepared in this way. Using a confocal microscope with an interferometric mode, the geometrical structure of the samples was analyzed. The optical strain gauge was used to measure the contact angle. Tribological tests were carried out in conditions of technically dry friction. The polished sample with the coating was characterized by a more stable course of the friction coefficient, lower wear and a smaller wetting angle

Weighted Radon transforms for which the Chang approximate inversion formula is precise

We describe all weighted Radon transforms on the plane for which the Chang approximate inversion formula is precise. Some subsequent results, including the Cormack type inversion for these transforms, are also given

Tribological properties of diamond-like-carbon coating doped with tungsten

This paper presents the tribological properties of diamond-like-carbon coatings (DLC) doped with tungsten. The hardness of the DLC coating was determined using a micro-hardness tester. Friction tests were carried out on a tribometer in rotational motion in a 100Cr6 steel ball-disk association with a-C-H:W tungsten doped hydrogenated DLC coating. Tests were carried out with loads of 10 N, 25 N and 50 N under technically dry friction conditions. Using a scanning electron microscopy (SEM), the surface morphology was observed, and with a confocal microscope, the geometric structure of the surface was observed before and after the friction tests. The wetting angle of the samples was examined on an optical tensiometer for distilled water and diiodomethane. The results indicated that DLC coatings of the a-C:H:W type obtained by the PVD technique can be used in unlubricated high-load tribological systems