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The present work studies the tungsten carbide (WC/C) coatings deposited by using Plasma Enhanced Chemical Vapor Deposition (PECVD), with and without gases of Ar and N2. Volatile hexacarbonyl of W was used as a precursor. Their mechanical and tribological properties were evaluated. The following values were obtained by using deposition process with N2 of HIT = 19.7 ± 4.1 GPa, EIT = 221 ± 2.1 GPa, and coefficient of friction (COF) = 0.35 ± 0.09. Secondly, deposition without the aforementioned gas obtained values of HIT = 20.9 ± 2 GPa, EIT = 292 ± 20 GPa, and COF = 0.69 ± 0.05. WC/C coatings were annealed at temperatures of 200, 500, and 800 °C, respectively. Evaluated factors include the introduced properties, the observed morphology, and the structural composition of WC/C coatings. The process of degradation was carried out by using various velocities, depending on used gases and annealing temperatures.

Tungsten carbide (WC/C) layers are often researched due to their outstanding mechanical and tribological properties. Here, optimized indented hardness (H IT ), indentation modulus (E IT ) and coefficient of friction (COF) values were measured to study the effect of pressure and bias voltage on WC/C layers, deposited on

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The present study deals with the effects of laser surface treatment on microstructure evolution and wear resistance of AISI H11 hot work tool steel in quenched and tempered condition. The most upper laser-affected zone is characterized by re-melted microstructure consisting of dendrite cells with fresh non-tempered martensite, retained austenite and inter-dendritic carbidic network. The subsolidus microstructure just beneath the re-melted zone represents the most laser surface hardened zone consisting of fresh non-tempered martensite with fine and coarse carbides as a result of overheating the original QT substrate microstructure. The highest microhardness values in the range from 775 to 857 HV were measured for the LSH microstructure and the most softened microstructure exhibited the minimum hardness of 530 HV. The laser treated samples showed the improvement of their surface wear resistance by 35%.

The optimised indented hardness (H IT ) of WC/C coatings deposited using an RF magnetron sputtering technique in relation to the vacuum chamber pressure and bias is presented in this paper. Based on the investigation, the maximal values of hardness (ca. 22.3 GPa) and Young's modulus (ca. 298 GPa) are shown. Besides the hardness and Young's modulus values, the minimal value of the coefficient of friction (COF) ca. 0.29 was obtained. WC/C coatings were deposited with and without N 2 and N 2 + SiH 4 (in a gas mixture) and they were subsequently annealed at 200 °C, 500 °C and 800 °C. Finally, they were evaluated from the aspect of H IT , E IT , COF and morphology as well as from the structural composition of the WC/C coatings before and after annealing.

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The aim of present article was to consider the influence of annealing parameters on evolution of microstructure and mechanical properties of dual phase steel. Dual phase steel was annealed according to the three chosen cycles of annealing: into intercritical region (780°C), into austenite region (920°C) and into austenite region (920°C) by subsequently cooling into intercritical region (780°C) with the hold at the temperature of 495°C. Tensile tests of the heat-treated specimens were carried out. The obtained microstructure consists from three phases: ferritic matrix, austenite and martensite. Nanoindentation experiments were performed with the peak load of 19.62 mN for ferrite grains and 0.981 mN for austenite and martensite grains, using a Berkovich tip as an indenter. The nanohardness for ferrite and martensite was 2.5 ±1 GPa and 7.1 ±1 GPa and for austenite the nanohardness varied from 4.1 to 4.5 GPa.