CHARACTERISTICS OF THE MICROSTRUCTURE AND GRAIN SIZE OF S690QL STEEL IN THE HARDENED AND TEMPERED STATE
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 an...
By Mirsada Oruč, Aida Imamović, Almaida Gigovic-Gekic, Milenko Rimac
PROPERTIES OF AUSTENITE STAINLESS STEEL X8CrNiS18-9 MICROALLOYED WITH TELLURIUM
More recently 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 than...
By Derviš Mujagić, Aida Imamović, Mustafa Hadžalić
MICROSTRUCTURAL DEGRADATION OF BOILER HEADERS STEELS UNDER LONG TERM EXPOSURE TO HIGH TEMPERATURE
This paper describes the process of degradation of the structure of the inlet header of the intermediate reheater (MPr) 2 input header at the boiler of Unit 7 of the Thermal Power Plant Kakanj, determined on the basis of tests of replicas and hardness at characteristic places of the header. Headers, with minor delays, have been in co...
By Armin Husika, Belma Fakić, Milenko Rimac
CALCULATION OF THERMAL CONDUCTIVITY FOR CRYSTALLINE NANOSTRUCTURES
We have introduced a theory for the calculation of thermodynamic characteristics for somecharacteristic nanostructures (ultrathin films and superlattices), using the adapted method of twotimetemperature Green's functions. In this paper, we have determined the coefficient of thermalconductivity using the definition of free energy and then compared t...
By Siniša M. Vučenović, Jovan P. šetrajčić
CHARGE CARRIERS STATES IN A MODEL OF CuO SUPERCONDUCTIVE CERAMICS
The translational symmetry of the distribution of atoms (ions) of the charge carriers (electrons orholes) system is broken by sputtering (doping),and due to the existence of two boundary surfaces.This is a model of high-temperature superconductors in which the observed symmetry breakingorthogonal to the CuO plane is treated as a perturbation. Singl...
By Jovan P. šetrajčić, Siniša M. Vučenović
CATECHOLASE ACTIVITY AND SUBSTITUENT EFFECTOF NEW HOMOLEPTIC COPPER(II) CHALCONE COMPLEXES
Three new neutral complexes of copper(II) containing chalcone ligands derived from 2'-hydoxyacetophenone and 4-substituted benzaldehydes were synthesized. Complexes were preparedby solution synthesis and characterized by spectroscopy. The catalytic activity of complexes wasexamined in the reaction of 3,5-di-test-butyl catechol (DTBC) oxidation. The...
By Selma Hadžalić, Irnesa Osmaković, Adnan Zahirović
THE ROLE OF WOOD-BASED PRODUCTS IN SUSTAINABLE DEVELOPMENT
Wood is renewable, recyclable, climate-friendly material, and presents an important segment inachieving circular economy and sustainability concepts. To be able to link these two concepts,production and consumption systems need to transform towards sustainability. Wood-basedproducts play a role in mitigating climate change by reducing carbon from t...
By Petar Ćurić, Jelena Obranković, Andreja Pirc-Barčić
METALOGRAPHY IN BOSNIA AND HERZEGOVINA BEFORE 30 YEARS AND TODAY
In modern times, the science of materials cannot be imagined without metallography. The history of metallographic testing in Bosnia and Herzegovina is primarily related to Zenica. Today, most of the research related to the metal industry in BiH is conducted in laboratories at the Kemal Kapetanović Institute in Zenica. The Institute's Metallog...
By Belma Fakić, Adisa Burić, Edib Horoz
HEAT RESISTANCE OF HK30Nb STAINLESS STEEL PIPE CASTING
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 fo...
By Mirsada Oruč, Alen Delić, Almaida Gigovic-Gekic, Raza Sunulahpašić
TESTING SURFACE ROUGHNESS AFTER DIFFERENT TECHNOLOGICAL PHASES OF PROCESSING NIMONIC 80A
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 ex...
By Raza Sunulahpašić, Mirsada Oruč, Edina Karić