Authors

The Characterization of Phase Transformations in Rapidly Solidified Al-Fe
and Cu-Fe Alloys through Measurements of the Electrical Resistance and DSC
abstract, article page 281 - 286 pdf - 1755 kB

A Study of the Microstructure and Mechanical Properties of Continuously
Cast Iron Products abstract, article page 287 - 290 pdf - 1259 kB

M. Bizjak, L. Kosec, B. Kosec, I. Anžel - The Characterization of Phase Transformations in Rapidly Solidified Al-Fe and Cu-Fe Alloys through Measurements of the Electrical Resistance and DSC

     For the characterization of the phase transformations in the alloys during the heat treatment the various methods of the thermal analyses are available. Thermogravimetry, differential thermal analysis (DTA) and the differential scanning calorimetry (DSC) are the most frequently used methods. The phase transformations proceed in two stages, i.e. nucleation and the growth of the new phase. Both processes are closely linked with the movement of the atoms. Rapidly solidified alloys often contain the elements with the low diffusivity. During the transition from the unstable to the stable state the energy changes are small, therefore the characterization of the changes by DTA, DSC is very difficult and could not be measured. During the heat treatment the phase transformations of the rapidly solidified alloys of Al-Fe and Cu-Fe were successfully detected by the simultaneous measurements of the electrical resistance, and were compared by the DSC method. By determination of the temperature regions of the phase transitions or temperatures, where the dynamics of the changes is maximal, the samples were heat treated and analysed by the scanning and transmission electron microscopy respectively. pdf - 1755 kB

S. Bockus - A Study of the Microstructure and Mechanical Properties of Continuously Cast Iron Products

     The horizontal continuous casting has a lot of advantages in comparison with traditional casting methods. But it has a few disadvantages and unsolved problems. The objective of this research was the experimental investigation of the effect of chemical composition of cast iron and the casting conditions on the microstructure and properties of continuously cast ingots. As a result, tensile strength, Brinell hardness, and pearlite content increased with increasing Cr, Cu, and Sb additions and decreasing carbon equivalent. As for microstructure of graphite, higher silicon to carbon ratio and lower solidification rate decreased a zone of interdendritic graphite. Nomograph of continuously cast iron structure was made. pdf - 1259 kB

S. V. Dobatkin, J. Zrník, I. Mamuzić - Nanostructures by Severe Plastic Deformation of Steels: Advantages and Problems

    The aim of this paper is to consider the features of structure evolution during severe plastic deformation (SPD) of steels and its influence on mechanical properties. The investigation have been carried out mainly on low carbon steels as well as on austenitic stainless steels after SPD by torsion under high pressure (HPT) and equal channel angular (ECA) pressing. Structure formation dependencies on temperature deformation conditions, strain degree, chemical composition, initial state and pressure are considered. The role of phase transformations for additional grain refinement, namely, martensitic transformation, precipitation of carbide particles during SPD and heating is underlined. pdf - 2425 kB

J. Zrník, I. Mamuzić, S. V. Dobatkin - Recent Progress in High Strength Low Carbon Steels

    Advanced High Strength (AHS) steels, among them especially Dual Phase (DP) steels, Transformation Induced Plasticity (TRIP) steels, Complex Phase (CP) steels, Partially Martensite (PM) steels, feature promising results in the field. Their extraordinary mechanical properties can be tailored and adjusted by alloying and processing. The introduction of steels with a microstructure consisting at least of two different components has led to the enlargement of the strength level without a deterioration of ductility. Furthermore, the development of ultra fine-grained AHS steels and their service performance are reviewed and new techniques are introduced. Various projects have been devoted to develop new materials for flat and long steel products for structural applications. The main stream line is High Strength, in order to match the weight lightening requirements that concern the whole class of load bearing structures and/or steel components and one of the most investigated topics is grain refinement. pdf - 3032 kB

J. Dańko, M. Holtzer - The State of Art and Foresight of World’s Casting Production

    The state of art and foresight of world’s casting production is discussed in the paper on the basis of the latest statistical data. The progress gained during the last few years in foundry engineering is shown as a way to further development of foundry technology. pdf - 2113 kB

Z. Keran, M. Skunca, M. Math - Finite Element Approach to Analysis of Axisymmetric Reverse Drawing Process

    The intention of this research is to make analyze of deep drawing Cr-Ni stainless steel process. The research is related to forces that appear in machine tool during the process and also to material stress and its behaviour. The results are taken from two sources and their comparison is made. The first source of results are experiments made on hydraulic press, and the other source are results obtained by creation of finite element model (FEM) and process simulation on MSC Marc Mentat program package. The measurements are made in cases of different reduction coefficient and different tool material. Comparison that is given is related to punch and pressure plate forces, and the state of material stress for each reduction coefficient is observed too. Datasheets and force diagrams present the results, and material stress can be seen on figures that are result of the simulation. pdf - 1285 kB

P. Virdzek, K. Teplická - Progressive Methods in Design and their Application in Engineering Industry

    The problem of a product‘s life cycle against R&D time has occurred due to changes in the behavior of customers. One possibility how to solve this problem is to use Information technologies and the concept of CIM (Computer Integrated Manufacturing) that considerably reduces R&D time, production time and the time to market. The CIM conception is based on the utilization of single modules (CAx systems) in the Design and Production planning area, manufacturing area (CAD/CAPP/CAM) and others, integrated together into one functional unit. pdf - 830 kB