THE MICROSTRUCTURE OF THE SCALE FORMED DURING THE HIGH TEMPERATURE OXIDATION OF A FeCrAl ALLOYS
FeCrAl alloys have good oxidation resistance at elevated temperature owing to the formation of a continuous Al2O3 surface film, which acts as an oxygen diffusion barrier. The aim of the present study was to investigate the early stages of protective oxide layer formation and its growth on specially prepared commercial FeCrAl alloys, Kanthal AF (K-A...
By Stojana Veskovič, Milan Bizjak, Blaž Karpe, Aleš Nagode, Samo Smolej, Janez Kovač, Gorazd Kosec
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
OPTIMISATION OF CHAMBER FURNACE TECHNOLOGICAL PARAMETERS FOR HIGH CHROMIUM STEEL ROLLS HEAT TREATMENT
In this work, industrial control technical measurements of the heat treatment of high chromium steel (HCS) rolls is presented.Measurements were carried out on the gas fired car bottom chamber furnace Bosio PP-KP 70/1150 in the company Valji d.o.o., Štore, Slovenia. Temperature measurements of the individual heating zones of the furnace, roll...
By Blaž Karpe, Simon Rečnik, Aleš Nagode, Borut Kosec, Sergej Novak, Stjepan Kožuh
EVALUATION OF THE MICROSTRUCTURE AND PHASE TRANSITION TEMPERATURES OF THE Cu-9%Al-8%Mn SHAPE MEMORY ALLOY
Shape memory alloys (SMAs) belong to the group of advanced functional materials for numerous technical applications. Among many known Cu-based shape memory alloys, Cu–Al–Mn ternary alloys are characterized by a combination of good shape memory properties and excellent ductility which makes them commercially attractive.In this work the C...
By Dragan Manasijević, Tamara Holjevac-Grgurić, Ljubiša Balanović, Uroš Stamenković, Radiša Todorović, Milan Gorgievski1, Mirko Gojić
INFLUENCE OF HEATING RATE ON STABILITY OF AUSFERRITE MICROSTRUCTURE
Austempered Ductile Iron (ADI) is obtained by exactly controlled heat treatment process of nodular cast iron. Ductile iron samples are first austenitised to dissolve carbon, then quenched rapidly to the austempering temperature to avoid the formation of deleterious pearlite or martensite. Resulting ausferrite microstructure consists of acicular fer...
By Hasan Avdušinović, Almaida Gigovic-Gekic, Šehzudin Dervišić
COMPARISON OF DIFFERENT STEEL TYPES BY USING 3D TOMOGRAPHY
The results of two light optical tomographies (LOT) of two-phase steels are presented and compared in this paper. Two-phase steels show a microstructure consisting of a carbon-rich second phase and a ferritic matrix. In this work, microstructures are compared with a martensitic and a bainitic second phase. Tomographies are very important for materi...
By Emina Vardo, Jessica Gola, Frank Mücklich
EFFECT OF UNEVEN PLASTIC DEFORMATION ON WIDTH OF CLAD LAYERS OF EXPLOSIVE WELDED THREE-LAYERS STRIP
The purpose of this paper is to describe the basic reasons for obtaining narrower clad layers of CuZn10 alloy in regards to the central layer of steel strip DC04 are described. Some reasons for the reduction of the thickness of clad layers along the side edges of the strip are also described, as well as the change in the length of these parts with ...
By Omer Beganović, Almedina Čamdžić, Faik Uzunović
NEW EDITIONS OF THE STEEL AND STEEL CASTING DESIGNATION STANDARDS
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...
By Mirsada Oruč, Raza Sunulahpašić, Almaida Gigovic-Gekic, Sulejman Muhamedagić
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