Open Access Conference Proceedings

Abstract: Cavity erosion is a complex and localized phenomenon involving mechanical, chemical and metallurgical parameters. The development of new materials depends on understanding the relationship between microstructure and cavity erosion. [..] Read more

Abstract: Numerous engineering components which are in contact with liquid environments that are working under pressure can be degraded by cavitation erosion.The present paper study the improvement of cavitation erosion resistance of gray cast iron with lamellar graphite and pearlite microstructure by applying the nitriding thermochemical treatment.The cavitation tests were carried out on a vibratory device with piezoceramic crystals in accordance with ASTM G32 - 2016 standard.The material degradation is demonstrated by mass loss and erosion rate variation depending on the cavitation attack period. As reference material it was considered the same type of gray cast iron, subjected to softening annealing treatment. [..] Read more

Abstract: The main purpose of the research was to determine the effect of local laser heating on the tensile stress under load. The simulation results show that the different locations and the number of laser tracks (internal reinforcing ribs) on a thin-sheet surface had a great influence on the stress distribution during tensile loads. [..] Read more

Abstract: Many power plant operators are currently struggling with the problem of expiring the design life of components. The question often arises whether to continue the operation of the equipment or if it is already necessary to shut down/overhaul it. [..] Read more

Abstract: The main goal of this article is to present the results of state the microstructure in chromium ledeburitic tool steel commercially named Sverker 3. This material was treated by austenitizing at various temperatures and then quenched in oil. [..] Read more

Abstract: According to the three-dimensional digital model additive production as a method of product manufacturing allows creating complex-profile structures with high mechanical and operational specifications. Metal products structuring in accordance with the process of their production is of considerable interest. [..] Read more

Abstract: In December 2017 there was a crash of footbridge in Prague – Troja. This failure led to an increase in interest in current status of prestressed concrete stress-ribbon bridges in the Czech Republic and maximum effort to prevent another accident. [..] Read more

Abstract: Small punch test is very useful method for evaluation of actual material properties of components especially in power industry. Two standards cover small punch test method – European standard and ASTM standard. [..] Read more

Abstract: The temperature of the hot bending of creep resistant steels is usually performed above the transition temperature Ac3. The steel thus undergoes a short-term austenitization followed by martensitic and/or bainitic transformation during subsequent fast cooling. [..] Read more

Abstract: The present work aims to demonstrate artifacts and errors in visualization of retained austenite phase in TRIP steel by an electron back-scattered diffraction (EBSD) technique. Retained austenite phases size and shape obtained by the EBSD are directly compared with a real image of these phases acquired by means of an atomic force microscopy (AFM). [..] Read more

Abstract: The experimental material consisted of semi-finished products of high-grade, medium-carbon constructional steel with: manganese, chromium, nickel, molybdenum and boron. The experimental material consisted of steel products obtained in industry metallurgical process in electric in a 140-ton basic arc furnace and desulfurized with argon-refined. [..] Read more

Abstract: The aim of the article is to analyse of the impact the double normalization process of 38MnVS6 micro-alloy steel on the achievement of the required microstructure and selected mechanical properties. The analysis was made based on values of elongation at break and the criterion of the minimum permissible breaking work. [..] Read more

Abstract: In the article, the technologies of deburring after pipe cutting are analyzed. The pipe cutting technologies and the external or internal burrs that are formed are described. [..] Read more

Abstract: Improving safety in mechanical engineering is still a topical issue. This article focuses on the introduction of a new thermochromic coating system, its development, and testing. [..] Read more

Abstract: The paper focuses on the evaluation of the ability of selected heat sprayed coatings to protect the surface of the component in an environment simulating the environment of a geothermal turbine. The subject of testing were coatings based on hardmetals, applied by HVOF technology (WC-CoCr, Cr3C2-NiCr) and Fe and Ni based alloys, applied by HVOF (NiCr, FeCrAlY) and TWAS (FeCrAlNiC, FeCr, NiCr) technologies. [..] Read more

Abstract: The article compares the methods of analysis of the surface chromium layer on two chromium-plated samples under the same technological conditions. However, both samples were visually different. [..] Read more

Abstract: The paper presents results of the research focused on testing of wear resistance of a selected case-hardening steel after application of a selected plasma nitriding technology. The steel equivalent 16MnCr5 (i. [..] Read more

Abstract: Due to the increasing requirements for ensuring the function of the component and technical units in operation, monitoring and influencing chemical and physical changes in the properties of materials in the surface layer of the component is of considerable importance. These changes take place both as a result of the machining process, but can also be significantly influenced by the formation of diffusion layers, using suitable surface technology. [..] Read more

Abstract: The article presents selected results of microstructural investigation of Ni-Cr-Re coatings deposited by means of plasma thermal spray. The substrate made of 16Mo3 chromium molybdenum boiler steel was sprayed with a powder material of Oerlikon Amdry 4535 80% Ni, 20% Cr, 20÷45μm, to which 1% of metallic rhenium was added. [..] Read more

Abstract: The paper presents selected results of microstructural investigation of NiCr-Re with the addition of aluminium oxide coatings, deposited by means of HVOF thermal spray. The substrate made of 16Mo3 chromium molybdenum boiler steel was coated with a powder material of Oerlikon Amdry 4535 80% Ni, 20% Cr, 20÷45 μm, to which 1% of metallic rhenium and 10% of Al2O3 was dopped using the high energy milling method in a ball mill. [..] Read more