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In the frame of latest requirements to improve the renewable energy harvesting, the wind turbines get more and more used. Due to the propeller sizes, the blades' materials must comply with high resistance and weight requirements. As consequence, composite materials with dedicated structures are used. These materials are designed for long life and, as consequence, are potential pollution factors for the environment, after turbine working life is ended. Beside the methods to destroy the blades and give other use to the material, the optimization of the maintenance and repair procedures stand as valuable way to reduce both the turbines cost and the environment contamination. Taking into account the working conditions of blades such as the presence of the abrasive particles (sand or dust) and the high rotational speeds that can be reached, following the wind speed, the assessment of wear resistance of blades in abrasive conditions stands as valuable information for both designing and repairing procedures. In the present work, an industrial blade composite material is analyzed and subjected to abrasive wear with sand particles flowing in air stream, simulating the wind effect. A dedicated test rig is used, allowing to change the wear process parameters. After the abrasive tests, the damage evolution was observed by optical microscopy to identify the most affected areas of the blade, which provides important information for establishing of repairing procedures. [ABSTRACT FROM AUTHOR]

The aim of this experiment was to compare the mechanical properties of the hoof horn of horses, mainly Czech warmblood, in relation to their stabling conditions - explicitly, grazing farming (pasture) with deep bedding stables. The sampling of the hoof horn was always made after a change of the horse's stabling method. This paper assesses the changes in some mechanical properties of the hoof as a result of changes in their stabling environment. Moreover, the hardness, the wear resistance and the impact resistance of the hoof horn was evaluated. The results of the experiment showed a statistically significant difference between the studied mechanical properties of the hoof horn and the compared stabling conditions. Conducting the experiment led to a new methodology for evaluating the mechanical properties of biological materials coming from polymeric testing. The experiment describes a possible methodology for testing biological materials based on the evaluation of the mechanical properties of inorganic polymers. An effect of the influence stabling environment has to the hardness and the impact strength of the hoof horn was confirmed. An effect of the influence stabling environment has on hoof's resistance against abrasiveness was not confirmed. [ABSTRACT FROM AUTHOR]

In Recycle plants, screening decrease in efficiency, increase in running costs due to wear of the crushing blade has become a serious problem. Therefore, the development of material excellent in abrasion resistance is required. In this study, using a spheroidal carbide cast iron material that is excellent in wear resistance are known, abrasive wear characteristics were evaluated using a Suga type wear testing machine. They are SCI-VCrNi, SCI-VMn, and SCI-W with hard (2400HV) spheroidal vanadium carbides (VC).As a result, It was found that high chromium cast iron Cr 17% compared to SCI-W has an abrasive wear resistance characteristics of five times. Even compared to high chromium cast iron is a high initial hardness, spheroidal carbide cast iron showed excellent wear resistance. Abrasive wear is not only dependent on the initial hardness of the material. Abrasive wear is considered, rather than the initial hardness, it is important to increased in hardness due to work hardening. [ABSTRACT FROM AUTHOR]

This article is devoted to the study of the chemical compositions of coating and the phases of applying coating during optimal conditions on samples of steel 30CrSi2. The studies were conducted by electrographic and X-ray diffraction methods. [ABSTRACT FROM PUBLISHER]

The paper presents the evaluation of resistance to abrasive wear by alloying the layers with the electrodes developed in "AnykščIų varies" Ltd. When simulating the wear, diverse pressure between contacting surfaces has been set up. Investigation of the strength of alloyed compositions to abrasive wear has proved that under low abrasive pressure to surface the greatest effect (wear is reduced 5.08 times) is done by high carbon (2.9%) layers amply alloyed with chromium(22 %), boron (0.71 %) and titanium (0.46 %). Using these materials under high contacting abrasive pressure, no wear difference has been noticed between these carbon layers amply alloyed with chromium, boron and titanium and thermally treated steels microalloyed with boron. [ABSTRACT FROM AUTHOR]