PROTAC 500 – ARMORED STEEL OF NEW GENERATION
In this work we studied the response of newly developed armored steel plates PROTAC 500 to the ballistic testing with armored piercing bullets with a core of tungsten carbide, charge 7.62 mm. Interactions between the bullets and the steel plate was investigated by standard metallographic and mechanical testing methods. We were interested in the geo...
By Jure Bernetič, Gorazd Kosec, Slavko Ažman, Matjaž Marčetič, Boštjan Podlipec, Borut Kosec, Aleš Nagode, Ladislav Kosec, Mirko Gojić, Milenko Rimac, Omer Beganović, Zijah Burzić, Franc Vodopivec, Iztok Tomažič
THE INFLUENCE QUENCHING AND TEMPERING ON PROPERTIES OF Cu-Al-Ni SHAPE MEMORY ALLOY
The paper presents comparison of microstructure and hardness of Cu-Al-Ni shape memory alloy before and after heat treatment (quenching at 900°C/60 min/water and tempering at 300°C/60 min/water). Microstructural analysis was obtained by optical microscopy (OM) and scanning electron microscopy (SEM) equipped with energy dispersive spectrometr...
By Mirko Gojić, Ivana Ivanić, Stjepan Kožuh, Milenko Rimac, Omer Beganović, Kemal Begović Begović, Borut Kosec
EFFECT OF MICROSTRUCTURAL CHANGES ON PROPERTIES OF COLD DEFORMED SINTERED COPPER AND Cu-Au ALLOY DURING THE ISOCHRONAL ANNEALING
This paper studies the effect of annealing on the microstructure and hardness, microhardness and electrical conductivity changes of cold deformed (ε=40%) sintered pure copper and Cu-4at.% Au alloy. The samples of pure copper and Cu-4at.%Au alloy were obtained by sintering, followed by prefinal rolling, quenching and final rolling with 40% r...
By Ivana Marković, Svetlana Nestorović, Desimir Marković, Dragana Živković
DISTORTION BEHAVIOUR OF C15E AND 42CrMo4 STEELS DURING HEAT TREATMENT
Dimensional tolerances of semi-products for the automotive industry became extremely narrow, and allow no deviations in the production process. In present research work the distortion behaviour of C15E (1.1141) and 42CrMo4 (1.7225) steels during two common industrial heat treatments (quenching and controlled heating and cooling) was ...
By Damir Česnik, Matej Rustja, Milan Bizjak, Blaž Karpe
MATERIAL STRENGTHENING IN FORMING FINAL TUBULAR PRODUCT FROM AL 99.5% BY FORWARD COLD FLOW FORMING
Final product of the cold forming process gain many advantages that are mostly produced by strengthening of the material in the process. Those advantages are primarily explained as improving mechanical characteristic of the work material. Forward cold flow forming is among those processes and it is mostly related to (forming) shaping...
By Sabahudin Ekinović, Ibrahim Plančić, Edin Begović, Himzo Đukić, Branka Muminović
NEW TECHNOLOGY CASTING OF COOPER ALLOYS USING THE GRAVITY BOTTOM POURING INTO WATER COOLED MOULDS
The study presents the results of researching and conquering the technology of gravity bottom pouring of cooper alloys in water cooled moulds. The new approach in this procedure is a specially projected gating system which enables the gating of liquid metal without any interruptions. Thanks to the skimmer inside the gating system, as...
By Bogić Vlaović, Zagorka Aćimović, Marko Pavlović, Ljubiša Andrić
SIMULATION OF THE THERMALLY INDUCED STRESSES IN AlMgSi INGOTS IN THE AREAS OF PRIMARY AND SECONDARY COOLING DURING DIRECT CHILL CASTING PROCESS
During the solidification of continuously cast ingots, thermally induced stresses generate casting errors as hot cracks, bending or residual stresses. Contraction mechanism and shrinkage due to solidification of the alloy which is in a pasty state induce occurrence of the above mentioned defects. Simulation of thermo - mechanical pro...
By Ana Beroš, Ivica Buljeta
STRENGTHENING OF NITRONIC 60 GRADE OF STEEL BY COLD DRAWING
In this paper the effects of the deformation strengthening mechanism on mechanical attributes are evaluated (toughness is not treated) during cold drawing of a corrosionresistant austenitic steel NITRONIC 60. Experimental evidence indicates that the technological factors of cold working by drawing significantly affect both the intensity ...
By Faik Uzunović, Omer Beganović, Sead Spužić
HEAT TREATMENT OF LOW CARBON STEEL SCREWS IN THE STRAIGHT FLOW FURNACE
Steels for screws, nuts and rivets are usually low carbon steels, carbon steels or quenched and tempered low alloy steels. From these are required precisely defined strength properties, hardness and toughness, which determine the so called class strength of screws. This paper describes the thermal treatment of hexagonal screws with s...
By Jusuf Duraković, Mirsada Oruč, Sulejman Muhamedagić, Raza Sunulahpašić, Almaida Gigović-Gekić
MODIFICATION OF CHEMICAL COMPOSITION AND THERMAL TREATMENT OF SEMIAUSTENITIC STAINLESS STEEL 17-7PH
Application of the new materials in the automotive industry is a challenge that is placed in front of researchers of our times. The challenge is reflected in the modification of the chemical composition of steel and heat treatment in order to achieve improved mechanical properties. Steel 17-7PH is austenitic - martensitic steel with ...
By Belma Fakić, Diana Ćubela, Mihyar Noureldin Mahmoud