The aim of the research was to analyze the delivered profile samples, where appeared the darker spots with an irregular circular shape on the surface of light colored profiles after process of natural anodizing without colouration. Profiles are manufactured with alloy EN AW 6060 (AlMgSi) according to EN 573-3, which was carried out by heat treatment hardening. For material were performed measurements of Brinell and Vickers hardness, Vickers microhardness and substructural analysis in occurrence area of the dark spots and outside of these spots (light area of profile). Based on these analyzes it revealed significant difference of mechanical properties in these individual areas and different substructure of the solid solution α there. Based on knowledge of heat treatment technology is this substructure heterogeneity and diversity of mechanical properties (hardness and micro-hardness) of the given alloy caused by uneven localized cooling after solvent annealing in the hardening process. The occurrence of inhomogeneities is then right to express to different color profile to the surface after the anodizing process.

The article is devoted to a comprehensive analysis of the coating of a component from the Ford Focus 1.0 l EcoBoost engine. It is one of a pair of materially identical aluminum gears connected by a drive pulley and a drive. Aluminum gear components are surface treated with a mixture of metal powders using PVD technology, where the goal of the coating is to increase the hardness, abrasion resistance and heat of the base material. The chemical composition of the basic material of the geared aluminum drive wheel of the FORD engine proves that it is a component made by thermoforming and corresponds to the alloy EN AW 6061 (AlMg1SiCu) according to the standard ČSN EN 573 1-3. The microstructure of the base material component exhibits fine intermetallic phases evenly distributed throughout the cross-section of the base base material, without the occurrence of larger inclusions and/or porosity. The cross-sectional microstructure in the area of the coating demonstrates that the component has a continuous uniform surface layer of the coating formed without a defect and does not have a diffuse bond with the base material. The measurement of the coating thickness of the component shows a continuous surface layer formed by powder metallography, which ranges from 70.1 µm to 143.9 µm. The surface EDS of the surface proves that it consists of deposited tungsten carbides produced by powder metallography and the bonding material is cobalt. Area EDS analysis of the surface coating identified morphologically two distinct areas of dark and light, where tungsten carbides and cobalt are based, and only the tungsten carbide and cobalt carbide contents change. The oxygen and carbon content also changes in the dark and light areas.

The article deals with the process of torque camshaft at a constant speed. The method of release was determined by the normal force acting between the cam and the tappet. Subsequently, was expressed torque. A prerequisite for the calculations are a constant friction coefficient between the components of the mechanism and constant speed of the camshaft. Cam used for the purposes of this study generated polynomial lifting dependence. Part of this work is the calculation methodology lifting addiction. Course of torque is the conclusion presented on the values of the corresponding measuring station, which is the result of previous work on the subject.

No abstract

Commercially supplied inoculation wires have a guaranteed chemical composition but not the size and distribution of individual phases, which are very important for nucleation. Therefore, two commercial alloys used for the inoculation of Al-Si alloys (AlTi3B1 and AlTi5B1) are investigated in this paper. The emphasis is placed on their structural analysis and the size and distribution of individual intermetallic phases. Furthermore, the grain refinement effect will be tested by adding these alloys to the AlSi7Mg0.3 alloy and testing the optimal amount of added inoculation wires. The results showed that the size and distribution of the individual phases in AlTi3B1 and AlTi5B1 meet the requirements for the successful inoculation of aluminum alloys, the intermetallic phases based on the TiAl3 phase are fine enough, and there is no agglomeration that would reduce the number of nuclei. This assumption was confirmed by adding these inoculants to the AlSi7Mg0.3 alloy, and it was found that the most ideal amount of inoculants added is 0.01 wt % when the structure was refined by approximately 32%.