EVALUATION OF TiN COATING PROPERTIES DEPOSITED ON HS6-5-2C STEEL

The article presents selected properties of TiN coating on HS6-5-2C steel by Physical Vapour Deposition (PVD). The coating thickness was measured with a Calotest, and its hardness was measured with a nanohardness tester. Tribological parameters were determined, namely, the coefficient of friction and linear wear on the TRB3 tester operating in a ball-on-disk sliding friction pair. The disc was made of HS6-5-2C steel with a TiN coating and the ball of 100Cr6 steel without coating and with a-C:H coating, with Al2O3. The tests were performed under technically dry friction conditions. The coating structure observations were made using a scanning microscope, and the analysis of the geometric structure of samples, before and after tribological tests, were performed with an optical profile measurement gauge. The test results showed that the lowest linear wear was obtained for friction pairs with an Al2O3 ball and a steel ball with a-C:H coating applied.

Influence of Zr Doping on the Tribological Properties of Amorphous Carbon-Nitride Coating

This study aimed to understand the influence of small amount of Zr doping of amorphous carbonitride (a-CN) coatings on the structure, and mechanical and tribological behavior. The coatings were prepared using a four-target close-field unbalance magnetron sputtering system; two graphite, one Ti and one Zr targets were used. GDOS, SEM, XRD and XPS were used. A surface profilometer, a nanohardness tester, and a pin-on-disk wear tester were used. It was found the Zr doping resulting in the formation of ZrC and ZrN phases within the coating and the increase in the sp3 bonding fraction. The nanohardness was increased and the wear performance was largely improved.

Partial Melting, Segregation Behavior and Nanomechanical Properties of AlCu2Si1Mg0.6 Alloy

The microstructure, phase composition and nanomechanical properties of AlCu2Si1Mg0.6 alloy was studied where partial melting of grain boundaries during quenching. It was assumed that the following two low-melting eutectics were present along the grain boundaries: α-Al+Cu2Al+Mg2Si and α-Al+Al15(Fe,Mn)3Si2+Si. The measurements of nanohardness and the Young’s modulus in the sub micro volumes were carried out by means of the nanoindentation method using a NanoScan-4D scanning nanohardness tester. An algorithm offered is for calculating the additional pressure that occurs when the mechanical action on the metal having a partial melting of grain boundaries.

The Impact of the Deposition Parameters on the Mechanical Properties of Thin Carbon Layers

The article describes the effect of the pressure in the chamber during the deposition of thin layers on the basic mechanical properties of thin layers based on carbon. Monitoring parameters are mainly nanohardness, coefficient of friction and adhesion between the layer and substrate. This parameters are observed using nanohardness tester and scratch tester. All observed layers had the same thickens of layers. Carbon layers generally have poor adhesion to the substrate. To improve the adhesion, is used the interlayer of titanium which is between the substrate and carbon layer. Carbon layers are mostly used for their very good sliding properties especially in cases where can not be used process fluids or where is necessary to reduce the friction between the two materials. The carbon layer can also be used in medicine (for their biocompatibility), for machine tools (for their hardness and abrasion resistance) or as barriers layers (for their high chemical resistance).

Composite Layers TiAlIntermetallic/PVD Coating Obtained by Hybrid Surface Treatment Technology on Aluminium Alloys

The paper presents the results of tests on an “intermetallic layer TiAl / coating AlCrTiN" hybrid layer, which was obtained using a hybrid method combining magnetron Sputtering, diffusion, and arc evaporation in a single technological process. The hybrid layer obtained was subjected to studies on morphology and chemical composition using the TM3000 scanning electron microscope. Additionally, hardness and Young's modulus as a function of distance from the surface were measured using a nanohardness tester CSM. Based on the analysis of the results obtained, the authors suggest the mechanism of layer growth in the technological process. The composite layer was also subjected to wear resistance using the ball-cratering method and erosion resistance tests using the glass powder. The obtained results showed that the Ti-Al intermetallic / AlCrTiN hybrid layer significantly increases resistance to abrasion as well as erosion wear resistance of the Ak12 alloy.

Effects of Aluminum Content on Oxidation Behavior of W-Al Nanolayer Coatings

A series of W-Al nanolayer coatings were deposited with varying content of aluminum from 0 at.% to 65 at.% by a unbalanced magnetron (UBM) sputtering system. The as-deposited coatings were investigated first. Then, the coatings were oxidized aiming to study their oxidation behavior. SEM, TEM, XRD, GDOS and nanohardness tester were used. The results showed that the Al content had a significant effect on the performance of W-Al coatings. The hardness of as-deposited and oxidized coatings decreased with increasing Al content. The pure W coating was heavily oxidized. As the Al content increased, the oxidation decreased fast and then remained stable as the Al content was higher than 45at.%. The effects of formed oxides on hardness were discussed.