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EN
In this work, AlCr and AlCrFe coatings were deposited via magnetron sputtering on technical substrates of carbon steel C45 and titanium grade 2. The coatings feature an amorphous structure, a thickness of 3-4 μm, and are uniform in terms of thickness and chemical composition. No major defects were visible at the interface; however, there is no diffusion at the interface, which indicates the adhesive type of bonding and results in relatively low adhesion. The coatings are characterized by a hardness of about 8-10 GPa and a Young modulus above 150 GPa. Both values are slightly higher for steel substrate. The coatings assure good corrosion resistance for steel substrate while underperforming those of Ti grade 2.
EN
The article discusses the ductility and formability of ultrafine-grained 3003 aluminum alloy plates processed using incremental equal channel angular pressing. The influence of temperature and strain rate is evaluated by means of tensile tests and cupping tests under various conditions. It is reported that tensile elongation increases two-fold at elevated temperature, without excessive grain growth. With the right selection of processing conditions, the formability of the plate, expressed as cup height deformed in a cupping test, can be enhanced—as much as 62% compared with room temperature when the processing takes place at 150 °C. The improvement in ductility was attributed to a reduced apparent activation volume due to grain refinement, which translated into improved strain rate sensitivity.
3
Content available remote Solid-state welding of ultrafine grained copper rods
EN
The article focuses on the Direct Drive Rotary Friction Welding of ultrafine-grained copper rods, which feature increased mechanical properties and good electrical properties, yet are limited in size. The use of UFG metals is often limited by the too small dimensions of semi-finished elements produced by SPD methods. Therefore, the production of finished machine parts from UFG metals is currently economically unjustified. Dismissal of dimensional limitations can be done by introducing joining to technological processes. The proposed joining method does not lead to a melting of the material in the joining zone or excessive degradation of the UFG microstructure. To obtain the best results, the research used the method of low-energy welding of two kinds of specimens: with a flat or a conical contact surface. In the article, the authors present, by means of metallographic microsections and microhardness measurements, the influence of rotational speed, welding pressure and conical shape contact surface on the quality of the obtained joints. The conducted research made it possible to obtain good quality joints whose microhardness is reduced only by about 10% in comparison with the base material and the tensile strength dropped from only 397–358 MPa.
EN
The Neogene basaltoid intrusions found in the S-7 borehole in the Sumina area (USCB) caused transformations of the adjacent Carboniferous rocks. The mineral and chemical compositions of the basaltoides are similar to those of the Lower Silesian basaltoides. The transformations that took place in the vicinity of the intrusion were manifested in the formation of natural coke, the secondary mineralization of these rocks (calcite, chlorite, zeolites and barite) and in the specific distribution of rare earths (REY). Among REY, the light elements (LREY) had the highest share, while the heavy elements (HREY) had the lowest share. Regardless of the lithological type of the analyzed rock, with increasing distance from the intrusion, the percentage of MREY and HREY elements increases at the expense of the light elements LREY. All analyzed distribution patterns of the REYs are characterized by the occurrence of anomalies, which often show a significant correlation with the distance of sampling points from the basaltoid intrusion. The specific distribution of REYs in the vicinity of the intrusion of igneous rocks is an indication of the impact of hydrothermal solutions associated with the presence of basaltoides on the rocks closest to them located at a temperature of over 200°C
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