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Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Toughness testing is one of the most important and most applied dynamic tests of materials. Many materials are subjected to this test in order to ensure the safety of work in adverse conditions. Thus, for steel S690QL, which is a high-strength fine-grained structural steel in the quenched and tempered state, the minimum conventional yield stress ReH of 690 MPa with guaranteed toughness (Charpy impact energy) at a temperature of -40°C of 30 J is prescribed, for rolled plates with a thickness of 3 to 50 mm. In this work, testing and analysis of the results of impact energy at a temperature of - 40°C was carried out for 10 samples of plates of different thicknesses, produced from steel S690 QL. With these tests, the aim is to consider the segments of the technological process, which have an impact on the physical-metallurgical characteristics, primarily on the formed microstructure and grain size, which affect the toughness values at low temperatures. [ABSTRACT FROM AUTHOR]

Steel S690 QL is a high-strength quenched and tempered, fine-grained structural steel with a minimum yield strength of ReH of 690 MPa and with guaranteed toughness (Charpy) for rolled plates with a thickness of 3 to 50 mm. This paper presents the examination and analysis of the microstructure and grain size results after quenching and tempering. Also, the aim of the examination is to consider the segments of the technological process and its influence on the physical and metallurgical characteristics, primarily on the microstructure and grain size, which affect the tensile characteristics and toughness at low temperatures. [ABSTRACT FROM AUTHOR]

The production of titanium is very expensive, so it is interesting to research technologies that require lower costs, such as the HDH hydrogenation-dehydrogenation process technology, which is used for cheaper powder production from the waste material of titanium alloys. This paper presents the hydrogenation procedure of a recycled piece of the Ti6Al7Nb titanium alloy. Hydrogenation was carried out in a furnace for heat treatment at about 700oC in a hydrogen atmosphere. After hydrogenation, samples of the Ti-Al-Nb type alloy were mechanically crushed by the grinding process to a granulation below 120 μm. [ABSTRACT FROM AUTHOR]

The aim of this work is to determinate the temperature start of precipitation of the secondary phases in austenitic stainless steels with delta ferrite. Presence of the delta ferrite in austenitic stainless steel promotes the precipitation of the secondary phases especially carbides and sigma phase whose have effect on quality of steel. The microstructure was characterized after a solution annealing at 1030 ℃ followed by annealing in temperature range from 550 to 1000 ℃ for the time of 30 minutes and cooling in air. Etched samples were observed using optical microscopy and scanning electron microscopy. The delta ferrite content was determined by a Feritscope MP30. Analysis of microstructure showed that the first phases precipitate between 550 and 650 ℃ at α/γ boundaries and delta ferrite. Sigma phase starts to precipitate between 650 and 750 ℃ at α/γ boundaries. [ABSTRACT FROM AUTHOR]

Metallic materials thanks to the excellent combination of data on material properties are obtained by standardized and agreed testing of samples made from semi-finished or finished products. Metallic materials can be tested by different testing techniques. One of them is metallographic testing, for which a light microscope is used as a basic device. In order for the test workability and strength are very important construction materials. The most complete and most accessible group of results to the light microscope were reliable it is necessary to calibrate the microscope according to certain standards and guidelines, and by the national metrology standards. This paper describes the procedure for calibration of the light microscope at the Metallographic Laboratory at the Institute "Kemal Kapetanović" in Zenica, University of Zenica. [ABSTRACT FROM AUTHOR]

The ore consolidation process is a thermal process and it happens at the temperatures of the ore melting beginning, allowing the ore grains, additives and fluxes to be connected into a solid piece of sinter. The amount of carbon in the sinter mixture and the FeO content of the produced sinter affect the mechanical resistance of the sinter. Indicators of mechanical resistance of sinter are very important for evaluating the metallurgical value of sinter. How much of the sinter is grounded during transport to the blast furnace and in the furnace depends on the mechanical resistance. The amount of high-dust, the gas permeability of the furnace, and thus the furnace productivity and fuel consumption depends on the amount of fine fractions in the furnace. [ABSTRACT FROM AUTHOR]

Surface roughness is the totality of microgeometric irregularities on the surface of an object and it is caused by various factors, from which the most important are machining and processing techniques. This characteristic of the material is very important, especially in the case of high-quality materials designed for the demanding conditions of exploitation. In this work the tests of surface roughness Nimonic 80A were carried out. The tests were performed after the different tehnological phases during processing of Nimonic 80A using Sutronic 10 instrument. This instrument work on the principle of ultrasound which measures the aritmetic value of Ra, i.e. parameter for determining the surface roughness. [ABSTRACT FROM AUTHOR]

Proper calibration of the device is important to prevent potential sources of error, which ensures that the test results most effectively represent the value of the sample being tested. In microhardness testing, the loading force does not exceed 1.96 N. The test surface requires a more complex metallographic preparation, and the smaller the injection force, the surface must be finer prepared. Precision measuring microscopes with an accuracy of ± 0,5μm are used to measure the size of the prints. Calibration of the Zwick Microhardness Testing Device of the Kemal Kapetanović Institute Metallographic Laboratory was performed for measuring ranges HV 0.3. The permissible deviation of the device including the measurement uncertainty shall meet the requirements of the standard for this area. [ABSTRACT FROM AUTHOR]

The HK30Nb steel pipe casting was obtained by centrifugal casting. This steel is austenitic stainless steel grade AISI HK 30 and is standardized according to ASME SA-351 in as cast condition. HK 30 Nb steels not standardized i.e. it is HK 30 steel modified with niobium. In addition to the required mechanical properties, this steel is also tested for heat resistance because it is used at high temperatures. In this paper, the heat resistance testing was carried out on the HK 30 Nb stainless steel pipe casting for two temperatures (750 and 850 °C) according to the standard ASTM G 54-84. The mass change and rate of oxidation for different heating times (24, 48, 72, 96 and 120 hours) were determined. The results of the study are significant for the continued use of these materials at high temperatures in exploitation conditions. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

More recently a modified stainless steels have been used to produce various structural elements that work in complex operating conditions. Stainless steel X8CrNiS18-9 (standard EN 10088-3: 2005) is the most commonly used austenitic stainless steel due to its good machinability. This steel has high mechanical and working properties thanks to a complex alloying, primarily with the elements such as chromium and nickel. The content of sulfur present in the steel from 0.15 to 0.35% improves machinability. However, while sulfur improves machinability at the same time decreases the mechanical properties particularly toughness. The aim of this work is to determine the influence of boron, zirconium and tellurium on the mechanical properties the mentioned steel. Change of mechanical properties, depending on the chemical composition of the steel is simulated with MATLAB program. [ABSTRACT FROM AUTHOR]

Metallurgical coke, as a fuel and a reducing agent, also allows for the gas to go through a charge in the blast furnace. The coke must have a strength, porosity, reactivity and a uniform granulation, because reaction of CO2 at high temperatures in the furnace. There are various mathematical models for the optimization of coal blend, which allow the forecasting of mechanical properties of coke in cold conditions as well as at high temperatures and presence of blast furnace gas. The so-called Modified Basicity Index (MBI) model is used for forecasting the following coke quality parameters: CRI (coke reactivity index) and CSR (coke strength after reaction with CO2), based on the content of volatile matters and ash in coal, as well as the chemical composition of coal ash. In this paper will be given the calculation of coke quality parameters based on the mathematical model MBI. [ABSTRACT FROM AUTHOR]

In conducted research was made a characterisation of microstructure and powder NiCrAlY, before and after applying on the base material. Coating was carried out by using HVOF Diamond Jet procedure, which uses the kinetic energy of the metal particles produced by on explosion of combustible gases. Characterisation was based on chemical analysis of metals powder particles, their size and structural composition and testing the composition, and structure of the applied coating on iron base alloy A286 with intermetallic strengthening. We used the classical testing methods of composition of metal powder and coating and optical and scanning electron microscopy in determining the phase composition. By testing with scanning electron microscopy, it was found that at the joint is present aluminium oxide with the presence of yttrium oxide, which play a significant role in the prevention of high-temperature oxidation of the base material. At the joint areal so analyzed and the concentration changes in the content of alloying elements. In addition to determining the phase composition of applied metal coating was used and x-ray structure analysis concentration changes in the content of alloying elements. [ABSTRACT FROM AUTHOR]

The great development of the industry has caused the need for systematization in the classification of raw materials and finished products. For this reason, all industrialized countries have their own standards, so called national standards or norms for production and delivery. With the unification of European countries, and also for the import and export of products and raw materials, the so called- European standard or EN (euro norm) took the primacy. Thus, the designation of steel according to the EN standard has been taken into consideration, and as a standard for designation of steel and therefore steel casting in our country, the designation according to EN standards has been taken over by some of the methods of takeover. Thus, the European standards with the prefix BAS become Bosnian standards. Standards for designation of steel and steel products are basic for metallurgy and metal industry and are very often in B&H they are translated versions of European standards. However, any change or revision of the European standard requires the same for the BAS standards, and in this paper will be presented the latest changes to the EN and BAS standards related to the "Designation system for steels", i.e. changes will be shown for the basic standards, respectively EN 10027-1 and 10027-2 or BAS EN 10027-1 and BAS EN 10027-2. [ABSTRACT FROM AUTHOR]

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Quality is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Maintenance is the property of University of Zenica, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Proceedings on Metallic & Nonmetallic Materials is the property of University of Zenica, Faculty of Metallurgy & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)