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Original Scientific Paper
Preliminary Note
Review
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ARCHIVE 1996 - 2010
49
year issue
Metalurgija - Journal for Theory and Practice in Metellurgy
Metallurgy 49 (3) 145 - 288
PDF - 4014 kB
ISSN 1334-2576    UDC:669+621.7+51/54(05)=163.42=111     METABK: 49 (3) 145 - 288 (2010)
Authors
Original Scientific Paper
F. Vodopivec, B. Šuštaršič,
J. Vojvodic-Tuma, G. Kosec
Charpy notch toughness and hardness of reheated martensite and lower bainite
abstract, article page 149 - 154 PDF - 666 kB
M. Tonkovic Prijanovič,
L. Kosec
Heat affected zone in surfacing chromium ledeburitic steel
abstract, article page 155 - 160 PDF - 505 kB
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Preliminary Note
M. Mihaliková
Research of strain distribution and strain rate change in the fracture surroundings
by the videoextensometric methode
abstract, article page 161 - 164 PDF - 347 kB
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Review Paper
F. Chowaniec, J. Mannheim,
J. Raab, R. Talarek
Steel industry in new EU member states in comparison with the global trends
abstract, article page 165 - 168 PDF - 177 kB
J. Kliber, I. Mamuzić
Selected new technologies and research themes in materials forming
abstract, article page 169 - 174 PDF - 347 kB
R. Kawalla, M. Graf,
K. Tokmakov
Simulation system of multistage hot rolling process of flat products
abstract, article page 175 - 179 PDF - 257 kB
D. Vojtech
Challenges for research and development of new aluminum alloys
abstract, article page 181 - 185 PDF - 219 kB
YU. G. Gulyayev,
YE. I. Shyfrin,
I. Mamuzić,
D. YU. Garmashev,
N. A. Maximova
The modern trends of development of the pipe and tube industry
abstract, article page 187 - 190 PDF - 109 kB
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Other
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9th International Symposium of Croatian Matllurgical Society
article page 191 - 194 PDF - 95 kB
F. Vodopivec
70th Anniversary of Life Academician Ilija Mamuzić
article page 241 - 287 PDF - 551 kB
Top of Page
Original Scientific Paper

F. Vodopivec, B. Šuštaršič, J. Vojvodič-Tuma, G. Kosec - Charpy notch toughness and hardness of reheated martensite and lower bainite

     A high strength low alloyed (HSLA) V-Nb steel was heat treated to martensite and lower bainite with different grain size, reheated for 3 seconds at 750 °C and air cooled. Charpy notch tests were performed from -100 °C to 60 °C and the hardness assessed at room temperature. For as delivered steel and lower bainite, the upper shelf toughness was above 200 J and the transition temperature low, while, for martensite the upper shelf toughness threshold was aproximateky at 0 °C. After reheating, notch toughness was decreased moderatly for martensite and strongly for lower bainite. Independently on grain size, lower bainite was more propensive than martensite to embritlement after short reheating in the (a + ß) range. For martensite, the change of notch toughness was not related to change of hardness, as by lower hardness lower, also toughness was lower.
 PDF - 666 kB

M. Tonkovič Prijanovič, L. Kosec - Heat affected zone in surfacing chromium ledeburitic steel

     Tools get failured during work; wear is a major factor that contributes to failures. Damaged tools are replaced or filed. This paper describes typical changes that occur in the heat affected zone of tool (HAZ), which was repaired by surfacing with a TIG and with micro-plasma procedure. Microstructure of the steel on the repaired tool was analysed by an optical and scanning electron microscope. The tool was made of chromium ledeburitic steel type W.N. 1.2379 and it was repaired by surfacing steel type W.N. 1.4718. Changes in the HAZ also depend on the type of surfacing. Besides microstructural changes, dissolution of carbides, especially primary carbides. This way the concentration of the carbide-forming elements and carbon is increased in the base around the primary carbides in the HAZ so the result is so-called secondary eutectic or secondary ledeburite.
 PDF - 505 kB

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Preliminary Note

M. Mihaliková - Research of strain distribution and strain rate change in the fracture surroundings by the videoextensometric methode

     The paper deals with the strain distribution and the strain rate of material in the surroundings of its fracture. Three steels applied in the automotive industry (DP - dual phase steel, microalloyed steel HR 45 and IF - interstitial free steel) were used as the experimental material. The videoextensometric technique was used for sensing with CCD camera and computer. During the test, software records the coordinates of the centres of gravity of individual points, from which the respective strain values are then obtained. For individual steel grades, strain field maps in the fracture surroundings were plotted. The change in the strain rate in the fracture surroundings and at places more distant from the fracture was observed.
PDF - 347 kB

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Review Paper

F. Chowaniec, J. Mannheim, J. Raab, R. Talarek - Steel industry in new EU member states in comparison with the global trends

     Accession of the metallurgically significant countries of the Central and Eastern Europe to the EU in 2004 was conditioned by fulfilling the Restructuring Programs as the foundation for achievement of competitiveness and guarancy of viability. The Restructuring Programs, which fulfilling and regular monitoring had lasted 5 years, demonstrated the right of the significant position of the steel industry in the new EU members, especially in Poland, Czech Republic, Slovakia, and in Hungary. The objective of the article is to point to the key elements in context of steel industry global trends, regarding either production or especially utility values and total consumption. In this connection, privatization took an important role too.
PDF - 177 kB

J. Kliber, I. Mamuzić - Selected new technologies and research themes in materials forming

     The article gives a review of selected new technologies of materials forming. That is selected 10 procedures, first, high pressure torsion processing, at the end, metal injection molding. All the new procedures have good performance and in the future for expect more the application in industry.
PDF - 347 kB

R. Kawalla, M. Graf, K. Tokmakov - Simulation system of multistage hot rolling process of flat products

     By means of numerical simulation of process it is possible to predict the global and local properties of profiles after each step of deformation. Determination of the influence of each certain stage in experimental way is rather cost-based and therefore resource-demanding. This is the reason why in the past years and decades took place the significant advancement of modeling in connection with the application of the numerical approach. On basis of physical approach it is possible for example to predict the development of material and properties of deformed working piece at every one by one following stage of deformation. The great necessity consists in creating of fast simulation systems, which can rapidly estimate the influence of parameters of deformation process on the properties of product and devices. The significant attention is dedicated to the calculation in real time so that In-Line-Simulation makes it possible to control and to operate the processes and devices.
PDF - 257 kB

D. Vojtech - Challenges for research and development of new aluminum alloys

     Modern trends in research and development of new aluminum alloys are characterized in the present work. Although conventional wrought and casting Al-based alloys show good specific strength, as compared to steels or Ti-based alloys, there is still a potential for significant improvement of their performance. It consists in application of new alloying elements, mainly transition metals, and uncommon processing routes, for example powder metallurgy. By this way, qualitatively new materials with ultra high strength and excellent thermal stability can be developed. However, there are many questions to be answered before new alloys can be competitive to conventional Al-based materials.
PDF - 219 kB

YU. G. Gulyayev, YE. I. Shyfrin, I. Mamuzic, D. YU. Garmashev, N. A. Maximova - The modern trends of development of the pipe and tube industry

     First the paper presents a review of steel production of the tubes in world: possible potencial is about 110 × 106 the tons (35 × 106 seamless tubes, rest welding tubes). In 2007. y. was record volume of 88,6 ×106 tons in world; 6,5% of total production of steel in world. Ratio-weldeds tubes: seamless tubes 70:30%. Further in the article are presented urgent the problems of the pipe and tube industry.
PDF - 109 kB

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ARCHIVE 1996 - 2010