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Original Scientific Paper
Preliminary Note
Review
Review Paper
Professional Paper
ARCHIVES 1996 - 2004
40
year issue
Metalurgija - Journal for Theory and Practice in Metellurgy
Metallurgy 64 (68) page
ISSN 1334-2576    UDC: 669+51+53+54(05)=862=20=30    METABK: 40 (1) 1 - 64 (2001)
Authors
Original Scientific Paper
A. M. Dolzhanskiy,
V. M. Druyan, M. Golja
Technological Lubricants Research in Wire Drawing Process
abstract, article page 5 - 11
G. Rosenberg

Fatigue Limit and Growth of Small Cracks in Notched Specimen
 abstract, article page 13 - 18

Authors
Preliminary Note
M. Godec,
M. Jenko
Texture Investigation of Electrical Steels
abstract, article page 19 - 22
A. Jaklič, T. Kolenko,
B. Glogovac
Simulation of Billet Reheating Process in Walking Beam Furnace
abstract, article page 23 - 27
B. Kosec, F. Kosel,
L. Kosec, M. Bizjak
Macroscopic Modelling of Two-Phase Metal Materials Subjected to
Plastic Deformation abstract, article page 29 - 32
G. Cukor,
M. Jurković
Contribution to the Stochastic Modelling of Plastic Processing
abstract, article page 33 - 36
I. Budić,
Z. Bonačić-Mandinić
Effect of Surface Treatment on Wall Thickness and Residual Stresses (RS)
in Castings abstract, article page 37 - 40
A. Drotlew,
M. Garbiak
Relationship Between Moulding Sand Composition and Size of Carbide Particles
in White Cast Iron abstract, article page 41 - 45
Authors
Review Paper
J. Kubicki,
B. Piekarski
Methods of Improvement of Resistance to Carburization of Creep-Resistant
Cast Steels abstract, article page 47 - 50
Authors
Professional Paper
P. Rybar, K. Kyselova,
M. Cehlar, M. Zacharov,
F. Sekula

Changes in the Properties of Remolten Biotitic-Quartzitic Gneisses from
„Branisko“, Slovak Republic abstract, article page 51 - 55
M. Mazankova
Heat Balance and Temperature Field of the System:
Casting - Mould - Surroundings abstract, article page 57 - 60
Authors
Review
I. Mamuzić
4th International Symposium of Croatian Metallurgical Society,
“Materials and Metallurgy” article page 61 - 63
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 Original Scientific Paper

A. M. Dolzhanskiy, V. M. Druyan, M. Golja - Technological Lubricants Research in Wire Drawing Process

     Quantitative and qualitative influence on the lubricant formation of the principal drawing factors such as die approach and its construction, metal constrained yield stress, dividing of flow, roughness and speed, lubricant state of aggregation of matter, its humidity and part dimensions was investigated. Conformity of the experimental data to hydrodynamic model of dry soap lubricant entrapment was proved.

G. Rosenberg - Fatigue Limit and Growth of Small Cracks in Notched Specimen

     Smooth, notched and precracked specimens were fatigued by bending at room temperature. The study presents the results of extensive fatigue tests carried out on steels, titanium and aluminum alloys and PM materials. The main objective of this study was to compare the fatigue limit of materials and the threshold conditions for the growth of fatigue cracks. The experimental results of crack propagation behavior were analyzed using a linear elastic fracture mechanics approach. The role of crack tip shielding in retarding the growth of fatigue cracks is also discussed.
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Preliminary Note
M. Godec, M. Jenko - Texture Investigation of Electrical Steels

    A complete description of a polycrystalline materials microstructure includes the grains’ sizes, shapes and arrangements as well as the distribution of the grains’ orientations. The orientation parameters of the crystallites are covered by the term texture. The majority of texture studies are made with the X-ray diffraction method. The principal a texture investigation in polycrystalline materials are reviewed. Finally, some examples are given concerning texture improvement of electrical steels alloyed with small Sn additions. The textures of the electrical steels are shown as pole figures, ODF functions and fibre textures. For those not familiar with texture measurements a simple explanation of how to interpret the texture results are also given.

A. Jaklič, T. Kolenko, B. Glogovac - Simulation of Billet Reheating Process in Walking Beam Furnace

     In the article a mathematical model of billets reheating is presented. The main heat transfer mechanism in the billet is thermal conduction which is calculated in two space dimensions by the finite difference method. The heat exchange between the billets, the furnace wall, and the furnace gas is evaluated by the modified “three temperature” Heiligenstädt method. The model is built for the real-time application and tested on the walking beam furnace at the Slovenian steel plant Metal Ravne.

B. Kosec, F. Kosel, L. Kosec, M. Bizjak - Macroscopic Modelling of Two-Phase Metal Materials Subjected to Plastic Deformation

     Deformation and fracture of multi-phase metal materials are two very important problems in the materials science and mechanical engineering. This article presents macroscopic models of two-phase metal materials, composed of ductile metal matrix and more rigid secondary-phase inserts. The components presenting matrices and secondary-phase inclusions and particles are magnified by a some orders of magnitude in comparison to the real two-phase metal materials. Two basic types of models have been developed: the first one on the basis of tensile deformation, and another one by a more complex way of the rolling deformation. The most important result of this investigation is the description of the kinematics model of the fracture of inclusion, and formation and elimination of the voids in ductile metal matrix with hard and brittle secondary-phase inclusions and particles.

G. Cukor, M. Jurković - Contribution to the Stochastic Modelling of Plastic Processing

     In this article, a model-building method, that enables both the adaptive estimation of model parameters and the utilisation of subjective previous information on the stochastic modelling of plastic processing, is proposed. It is based on the following idea: first of all, a basic model of the second-order polynomial form must be determined from the lowest possible number of starting experiments or by use of some subjective previous start-up data, and later the model reliability will be ensured by the adaptation of model parameters to the particular environment of plastic processing. The effectiveness of the proposed method is shown by the of cold extrusion force modelling example.

I. Budić, Z. Bonačić-Mandinić - Effect of Surface Treatment on Wall Thickness and Residual Stresses (RS) in Castings

    The article reports on results of operative testing, carried out with the purpose to establish the effect of number of passes of the casting through the shot peening machine on the wall thickness and RS ofthin-walled grey iron castings. The investigation results have been presented in the form of tables and diagrams, and proposals for further research have also been offered.

A. Drotlew, M. Garbiak - Relationship Between Moulding Sand Composition and Size of Carbide Particles in White Cast Iron

     The article presents the microstructural studies performed on white cast iron, which was sand-cast, using varied amounts of cast iron shot and plate thickness. The rate of heat flow during solidification and self-cooling of a casting is considered to be responsible for a kind and morphology of the precipitated phases. At high-chromium alloys the fraction and the size of carbides have a decisive influence on the wear resistance. The quantitative determination of the influence of the composition of moulding sand on the morphology of carbide phase offers the possibility to control the abrasive wear.
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Review Paper

J. Kubicki, B. Piekarski - Methods of Improvement of Resistance to Carburization of Creep-Resistant Cast Steels

   In this paper the results of investigations concerning the protection against high-temperature corrosion of grates and baskets used in carburizing furnaces have been presented. The investigations comprise the selection of both the chemical composition of material and protective coatings as well as the methods of coatings preparation. The influence of machining on the kinetics of carburization has also been investigated. It has been proved that the improvement in castings’ resistance to carburization can be achieved by introduction into alloy the elements such as nickel, chromium, niobium and titanium. The coatings of Al-Cu and Al-Si type applied on the surface of a casting are effective as well.
Top of page
Professional Paper
P. Rybar, K. Kyselova, M. Cehlar, M. Zacharov, F. Sekula - Changes in the Properties of Remolten Biotitic-Quartzitic Gneisses from „Branisko“, Slovak Republic

     Changes of the structural and physico-chemical properties after remelting at the a temperature over 1615 °C are presented. The chemical composition and the microscopic changes in the structure of mineral are investigated as well.

M. Mazankova - Heat Balance and Temperature Field of the System: Casting - Mould - Surroundings

    The numerical model of the system using finite difference simulation program is described in the presented article. The physical and mathematical models of the system are set up. The basic problem encountered is the solution of is the temperature field of the casting, especially with the respect to the phase transition. The heat is transferred into and throug the mould and the formulation of the boundary condition at the contact must be very precisely defined. A certain amount of heat is transferred to the surroundings and so the heat transfer coefficient from the outer surface of the system must be calculated. The knowledge of the temperature distribution in the casting and in the mould enables to evaluate the heat balance during the casting solidification period.
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ARCHIVES 1996. - 2000. (under construction): author(s) - name of the article - abstract