INFLUENCE OF MICROALLOYING WITH BORON, ZIRCONIUM AND TELLURIUM ON THE MODIFICATION OF NONMETALLIC INCLUSIONS OF AUSTENITIC STAINLESS STEEL WITH SULPHUR ADDITION
The basic characteristics of the chemical composition of steel with improved machinability (X8CrNiS18-9) are the increased content of sulphur (0.15-0.45%), phosphorus (0.07-0.11%) and manganese (0.5-1.5%). Sulphur by creating sulphide inclusions reduces friction and cutting resistance, and increases the brittleness of the chip.Considering its harmf...
By Derviš Mujagić, Aida Imamović, Mustafa Hadžalić
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
THE INFLUENCE OF THE RHEOLOGICAL PARAMETERS OF THE COAL MIXTURE ON THE STRENGTH OF METALLURGIC COKE
Metallurgical coke as a fuel, reducing agent and permeable material in high-pressure processes must have pronounced strength and granulation properties due to expected changes in high temperature conditions. The best quality of metallurgical coke is achieved when coal mixtures satisfy a certain range of rheological parameters. The characterization ...
By Sulejman Muhamedagić, Amina Kurtović, Azra Halilović
THE INFLUENCE OF CARBON IN SYNTER-MIXTURE ON THE MECHANICAL RESISTANCE OF THE PRODUCED SINTER
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. Indicato...
By Sulejman Muhamedagić, Mirsada Oruč, Amna Karić
TESTING THE DYNAMIC STRENGTH OFSUSPENSION LEVER OF MINE HOISTING EQUIPMENT
Mine development imposes very high technical requirements of the mine hoisting equipment in terms of speed of transport. To meet these requirements it is necessary to properly design the structural elements of mine hoisting equipment which means that they must have the proper characteristics of the materials from which they are made such as mechani...
By Mustafa Hadžalić, Mirsada Oruč, Raza Sunulahpašić
STUDY OF THERMAL PROPERTIES AND MICROSTRUCTURE OF THE Sn-Ag ALLOYS
Thermal properties and microstructure of the Sn-10% Ag and Sn-20% Ag alloys were experimentally investigated in this study. Melting behavior of the alloys were studied using differential scanning calorimetry (DSC). Microstructure of the alloys was analyzed by optical microscopy. The xenon-flash method was used for the measurements of thermal diffus...
By Dragan Manasijević, Ljubiša Balanović, Ivana Marković, Duško Minić, Aleksadar Đorđević
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
INVESTIGATION OF THE GENERAL CORROSION OF COPPER IN HYDROCHLORIC ACID
In this paper were investigated the effect of hydrochloric acid concentration and addition of oxidizing agents on the rate of general corrosion of copper.For comparison, the corrosion rate in distilled water was also tested.Taffel extrapolation method was used for investigation of general corrosion of copper. Taffel extrapolation method implies sca...
By Farzet Bikić, Dejana Kasapović
THERMAL PROPERTIES OF ARMOUR STEEL
The presented investigation work investigates thermal properties of the ultra-high hardness (UHH) armour steel. Steel is distinguished with high hardness and strength. It is sold in the quenched or tempered state, because achieving planned hardness which has to be between 590 HB and 640 HB. In the frame of the investigation work the analysis of the...
By Borut Kosec, Tjaša Kranjec, Blaž Karpe, Aleš Nagode, Milan Bizjak, Jure Bernetič, Mirko Gojić, Zijah Burzić, Milan Rimac, Gorazd Kosec