DUCTILE IRON MICROSTRUCTURE DESIGN USING HEAT TREATMENT PROCESSES
Mechanical properties of the ductile iron strongly depend on its microstructure. Different microstructural constituents result in different values of mechanical and ductile properties of ductile iron castings. One of the possibilities to design (define) microstructure of ductile iron castings is an application of different heat treatment processes....
By Hasan Avdušinović, Salaheldin Abdelmagid Mohamed Badreldin, Mohammed Abdelgadir Abdalla Mohammed, Faik Uzunović
HEAT TREATMENT OF LOW ALLOYED STEELS 17CrNiMo6 AND 20CrMo5 – CARBURIZATION
This paper is concerned with carburization heat treatment. Standard carburization generally entails several steps: carburization of the surface layer by carbon diffusion at high temperatures, subsequent hardening and stress relief. This combination of hard surface and resistance to breakage upon impact is useful in parts such as a cam or ring gear,...
By Belma Fakić, Mohamed Fadlalla Mohamed Ahmed, Babekir Ahmed Osman Mohammed, Faik Uzunović
EFFECT OF DEFORMATION AND HEAT TREATMENT ON MICROSTRUCTURE OF WARM ROLLED STEEL IN ALPHA-GAMMA AREA
In this paper the effect of different heat treatment (recrystallization, spheroidizing and normalizing) processes on microstructure of the steel DC04 intended for deep drawing is presented. The steel is cladded with CuZn10 layers by explosive welding. Since the melting temperature of alloy CuZn10 is significantly lower (melting range 1025-1045 oC) ...
By Omer Beganović, Belma Fakić, Ali Mohammed Ali Mohammedzain, Babekir Ahmed Osman Mohammed, Faik Uzunović
THE INFLUENCE OF THE ADDED AMOUNT OF GYPSUM ON THE PORTLAND CEMENT HYDRATION HEAT
Gypsum is added to the Portland cement clinker in the amount of 3 to 5% in the grinding phase as the binding rate regulator. When it comes to the hydration of cement, if sufficient amount of gypsum is added, fast cementation will not occur because gypsum by its presence reduces the solubility of tricalcium aluminate and thus slows down rapid reacti...
By Ilhan Bušatlić, Amna Karić
HIGH-STRENGTH CONCRETE (HSC) MATERIAL FOR HIGH-RISE BUILDINGS
Successful examples of high–rise buildings in the world are obvious evidences that the use of high–strength concrete is nowadays reality in construction worldwide. Whether focus on high–rise buildings up to 15– 24 storeys, or the super tall high–rise buildings that are few hundred of storeys high, high–strength c...
By Ilda Kovačević, Sanin Džidić
PROGNOSIS OF REACTIVITY AND STRENGTH OF COKE BASED ON MODIFIED BASICITY INDEX MODEL
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...
By Sulejman Muhamedagić, Mirsada Oruč, Admir Muminović, Amina Kurtović
CAVITATION OF REFRACTORY SAMPLES BASED ON TALC AND ZEOLITE FROM ZLATOKOP, SERBIA
Samples based on talc with 15 % of zeolite from Zlatokop, Serbia, sintered at 1200 ºC were prepared and tested in condition of cavitation erosion. The ultrasonic vibratory cavitation set up with stationary specimen was used. Mass loss was measured and degradation level of the samples using image analysis and Young modulus of elasticity was mon...
By Jelena Majstorović, Sanja Martinović, Milica Vlahović, Marina Dojčinović, Marko Pavlović, Tatjana Volkov Husović
EEFFECT OF VARIATIONS IN CHEMICAL COMPOSITION ON QUALITY OF HOT ROLLED AND DRAWN WIRE
Ratio of ultimate tensile strength and yield stress shows lower values in cold drawn wire than in hot rolled state. The results of research addressing the effect of variations in chemical composition of continuous casted billets on mechanical properties of cold-formed wire used in production of steel mesh are presented. In the c...
By Šaban Žuna, Aida Mahmutovic, Faik Uzunović, Sead Spužić
INFLUENCE OF HOLDING TIME ON AUSTENITIZATION TEMPERATURE ON GRAIN SIZE OF S355J2 STEEL
The austenitization is first operation at most operations of heat treatment, and it is implied heating steel on the austenitizing temperature and holding at this temperature while are not achieved completely transformation origin microstructure in austenite. Two base parameters which implicate at effect of austenitization are austeni...
By Armina Bašić, Almaida Gigović-Gekić, Hasan Avdušinović, Mustafa Hadžalić
SULFUR DIOXIDE AIR POLLUTION IN THE CITY OF ZENICA
In the city of Zenica steel is continuously produced more than 120 years. In all technological stages of production and processing of steel within integrated steel works large amounts of raw materials and fuels which contain a certain amount of sulfur are consumed. The flue gases formed during production and processing of steel contain certain conc...
By Sulejman Muhamedagić, Mirsada Oruč, Halim Prcanović