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Original Scientific Paper
Preliminary Note
Review
Review Paper
Professional Paper
ARCHIVE 1996 - 2010
49
year issue
Metalurgija - Journal for Theory and Practice in Metellurgy
Metallurgy 49 (1) 1 - 72
PDF - 2341 kB
ISSN 1334-2576    UDC:669+621.7+51/54(05)=163.42=111     METABK: 49 (1) 1 - 72 (2010)
Authors
Original Scientific Paper
G. Solenički, I. Budić,
D. Ciglar
Determination of thermal conductivity in foundry mould mixtures
abstract, article page 3 - 7 PDF - 155 kB
M. Muhič, J. Tušek,
F. Kosel, D. Klobčar,
M. Pleterski
Thermal fatigue cracking of die-casting dies
abstract, article page 9 - 12 PDF - 165 kB
W. Matysiak, B. Barišić,
I. Mamuzić
Elaboration of the technology of forming a conical product of sheet metal
abstract, article page 13 - 17 PDF - 139 kB
J. Terpák, L'. Dorčák,
J. Revaj
Quality control of the electro-discharge texturing
abstract, article page 19 - 22 PDF - 86 kB
S. Lasek, L. Střílková,
V. Číhal, M. Blahetová
Electrochemical testing of passivity state and corrosion resistance of supermartensitic stainless steels
abstract, article page 23 - 27 PDF - 192 kB
J. Bernetič, B. Bradaškja,
G. Kosec, E. Bricelj,
B. Kosec, F. Vodopivec,
L. Kosec
Centreline formation of Nb(C, N) eutectic in structural steel
abstract, article page 29 - 32 PDF - 119 kB
T. Matković, Lj. Slokar,
P. Matković
Effect of composition on the structure and properties of Ti-Co-Cr alloys
abstract, article page 33 - 36 PDF - 128 kB
D. Steiner Petrovič, M. Jenko,
A. Jaklič, A. Čop
Correlation of titanium content and core loss in non-oriented electrical steel sheets
abstract, article page 37 - 40 PDF - 109 kB
Home
Preliminary Note
M. Pleterski, J. Tušek,
L. Kosec, M. Muhič,
T. Muhič
Laser repair welding of molds with various pulse shapes
abstract, article page 41 - 44 PDF - 171 kB
P. Jelić, L. Lazić,
J. Črnko
The efect of cooling rate on the properties of alloyed cast-iron sizing roll
abstract, article page 45 - 48 PDF - 165 kB
F. Tehovnik, F. Vodopivec,
B. Arzenšek, R. Celin
The effect of lead on the hot workability of austenitic stainless steel with a solidification structure
abstract, article page 49 - 52 PDF - 163 kB
V. Marušić, S. Aračić,
I. Samardžić
The influence of the base material surface preparation on the properties of thermally sprayed coatings
abstract, article page 53 - 56 PDF - 154 kB
A. Karabulut
Determination of diametral error using finite elements and experimental method
abstract, article page 57 - 60 PDF - 170 kB
I. Leššo, P. Flegner,
M. Šujanský, E. Špak
Research of the possibility of application of vector quantisation method for effective process control
of rocks disintegration by rotary drilling
abstract, article page 61 - 65 PDF - 154 kB
Top of Page
Review Paper
J. Kliber, R. Fabík,
I. Vitez, K. Drozd
Hot forming recrystallization kinetics in steel
abstract, article page 67 - 71 PDF - 323 kB
Top of Page
Other
Editoral board of journal Metalurgija
Acknowledgement to reviewers
article page 72 PDF - 31 kB
Top of Page
Original Scientific Paper

G. Solenički, I. Budić, D. Ciglar - Determination of thermal conductivity in foundry mould mixtures

     For a thorough understanding of the behaviour of foundry mould mixtures, a good knowledge of thermal properties of mould materials is needed. Laboratory determination of thermal conductivity of mould mixtures enables a better control over scabbing defects which are a major problem in green sand mould mixtures. A special instrument has been designed for that purpose and it is described in this work.
 PDF - 155 kB

M. Muhič, J. Tušek, F. Kosel, D. Klobčar, M. Pleterski - Thermal fatigue cracking of die-casting dies

     Die-casting dies are exposed to high thermal and mechanical loads. Thermal fatigue cracking of dies due to thermal cycling may importantly shorten the life-time of the die. Cracks degrade the surface quality of dies and consequently the surface of castings. In this study, thermal fatigue cracking of dies was analyzed during the process of die casting aluminium alloys. During the process cracks were observed and measured and their location and size were determined. Thermal and mechanical loads cause high local stresses and consequently surface cracks. First cracks occur as early as after 2000 cycles and propagate progressively with cycles.
 PDF - 165 kB

W. Matysiak, B. Barišić, I. Mamuzić - Elaboration of the technology of forming a conical product of sheet metal

      The work presents a general knowledge about spinning draw pieces of sheets, one of multi-operational processes of spinning a sheet metal conical product without machining. The objective of the work was to elaborate both the technology of forming conical products of sheet metal and execution of technological tests as well as to determine the technological parameters for the process of spinning a conical insert. As a result of the investigations, the products with improved mechanical properties, stricter execution tolerance and low roughness have been obtained. The series of 200 prototype conical inserts for the shipbuilding industry have been made.
 PDF - 139 kB

J. Terpák, L'. Dorčák, J. Revaj - Quality control of the electro-discharge texturing

     This paper deals with quality control of the electro-discharge texturing. Automobile manufacturers have strict requirements for micro-geometry parameters of rolled metal plates from contractors of body sheet metal. The micro-geometry of the roll surface has significant influence on the final quality of the rolled metal plate. In this paper electro-discharge texturing parameters are analyzed, for example, the texturing current, impulse time, technological pause, and their impact to roughness average and peak counts. Quality control is discussed based on mathematical model for estimating the texturing current, impulse time, and technological pause for roughness average or peak counts required value.
 PDF - 86 kB

S. Lasek, L. Střílková, V. Číhal, M. Blahetová - Electrochemical testing of passivity state and corrosion resistance of supermartensitic stainless steels

     On low interstitial - supermartensitic stainless steels (X1CrNiMo 12-5-1, X2CrNiMo 13-6-2, X1CrNiMo 12-6-2) the electrochemical potentiodynamic polarization tests were carried out and the passive state stability and localized corrosion resistance were compared and evaluated. The effect of quenching and tempering as well as the changes in microstructure on polarisation curves and corrosion properties at room temperature were established. Small differences in chemical composition of steels were also registered on their corrosion parameters changes and resistance.
 PDF - 192 kB

J. Bernetič, B. Bradaškja, G. Kosec, E. Bricelj, B. Kosec, F. Vodopivec, L. Kosec - Centreline formation of Nb(C, N) eutectic in structural steel

     The reduction of area in the through thickness direction is an essential mechanical property of thick steel heavy plates. By a routine control, a very small through thickness reduction of area was found for tensile specimen of a 90 mm plate. Careful investigations of the fracture and section of specimens cut from the as solidified continuously cast 250mmthick slab showed that the cause was the presence of coarse particles of niobium carbonitride as constituent of the quasi eutectic Fe-Nb(C, N) that form because of the centerline segregation of niobium.
 PDF - 119 kB

T. Matković, Lj. Slokar, P. Matković - Effect of composition on the structure and properties of Ti-Co-Cr alloys

     The present work is a study of six as-cast Ti-Co-Cr alloys in the Ti-rich region with the purpose of examining the possibility of obtaining a new ß-type Ti-alloys. Two experimental alloys Ti80Co10Cr10 and Ti70Co10Cr20 are nearly single-phases and are identified as bcc ß-Ti phase. They also display the lowest hardness values and the best corrosion properties. The present study indicates that the region of biomedically-acceptable ternary Ti-rich alloys is situated within lower concentrations of alloying elements, i.e. about 10 at.% Co and 20 at. % Cr.
 PDF - 128 kB

D. Steiner Petrovič, M. Jenko, A. Jaklič, A. Čop - Correlation of titanium content and core loss in non-oriented electrical steel sheets

     In this study the correlation between the titanium content of steel and the core loss of non-oriented electrical steel sheets was determined. The core loss and titanium content of steel have a weak, but positive, correlation. The core loss was found to increase with an increasing titanium content. The study included a statistical analysis of an industrial data set and a metallographic analysis of the titanium inclusions. The analyzed titanium inclusions in the electrical steel sheets containing 0,006 mas.% Ti and 0,008 mas.% Ti were complex oxycarbonitrides, complex TiC and complex Ti(C,N).
 PDF - 109 kB

Home
Preliminary Note

M. Pleterski, J. Tušek, L. Kosec, M. Muhič, T. Muhič - Laser repair welding of molds with various pulse shapes

     Repair welding of cold-work tool steels with conventional methods is very difficult due to cracking during remelting or cladding and is generally performed with preheating. As an alternative, repair welding with laser technology has recently been used. This paper presents the influence of different pulse shapes on welding of such tools with the pulsed Nd:YAG laser. Repair welding tests were carried out on AISI D2 tool steel, quenched and tempered to hardness of 56 HRc, followed by microstructural analysis and investigation of defects with scanning electron microscopy. Test results suggest that it is possible to obtain sound welds without preheating, with the right selection of welding parameters and appropriate pulse shape.
PDF - 171 kB

P. Jelić, L. Lazić, J. Črnko - The efect of cooling rate on the properties of alloyed cast-iron sizing roll

     Directional heat transfer was investigated by temperature measurements in the casting and in the mould using thermocouples. Measurements were performed in operating conditions during pouring, solidification, and cooling of the casting. Total measurement time was 35,5 hours. After cutting, specimens were extracted for metallographic and hardness testing. Test results provided confirmation of directional heat transfer (directional cooling) that would ensure acquirement of a desired casting structure and mechanical properties.
PDF - 165 kB

F. Tehovnik, F. Vodopivec, B. Arzenšek, R. Celin - The effect of lead on the hot workability of austenitic stainless steel with a solidification structure

     The impurities sulphur, phosphorus, lead, bismuth, tin and antimony affect the hot workability of stainless steels. In this study we show that lead segregate to phase and solidification-grain boundaries, where cracks appear during hot deformation. The workability was tested by the hot bending of laboratory steels.
PDF - 163 kB

V. Marušić, S. Aračić, I. Samardžić - The influence of the base material surface preparation on the properties of thermally sprayed coatings

     Using specimens, a research was conducted to determine the influence of the base material surface preparation for 42CrMo4 on the final coating, prior to actual thermal spraying. During thermal spraying, an Al-Ni-alloy was used as an interlayer before the actual coating with Cr-Mo-Ni. The surface hardness and the hardness distribution across the thickness of the sprayed coating were measured and the structure of respective sprayed coatings was photographed. A comparison of experimental results enabled the identification of the particular material preparation method with an optimal ratio of the satisfactory coating thickness and its hardness.
PDF - 154 kB

A. Karabulut - Determination of diametral error using finite elements and experimental method

     This study concerns experimental and numerical analysis on a one-sided bound workpiece on the lathe machine. Cutting force creates deflection on workpiece while turning process is on. Deflection quantity is estimated utilizing Laser Distance Sensor (LDS) with no contact achieved. Also diametral values are detected from different sides of workpiece after each turning operation. It is observed that diametral error differs due to the quantity of the deflection. Diametral error reached a peak where deflection reached a peak. Model which constituted finite elements is verified by experimental results. And also, facts which caused diametral error are determined.
PDF - 170 kB

I. Leššo, P. Flegner, M. Šujanský, E. Špak - Research of the possibility of application of vector quantisation method for effective process control of rocks disintegration by rotary drilling

     The subject of the paper is investigation of the properties of concurrent vibro-acoustic signal in the process of rock massif separation with the method of rotary drilling. The aim is to investigate the possibilities of using this signal as an integrating information source for the purposes of identification of the process of separation from the viewpoint of efficiency of the set mode (pressure, revolutions, indentor) under current geotechnical conditions. Investigated is the possibility of recognition of the state of the process based on the method of vector quantisation.
PDF - 154 kB

Top of Page
Review Paper

J. Kliber, R. Fabík, I. Vitez, K. Drozd - Hot forming recrystallization kinetics in steel

     The theory of kinetics of static recrystallization of steel during hot forming links the phenomenon to certain critical strain, grain size, strain rate, activation energy and temperature. The basic description is provided by the Avrami equation. An overview of equations used was compiled and comments on selected parameters prepared.
PDF - 323 kB

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Original Scientific Paper
Preliminary Note
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Review Paper
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