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This paper presents the results of the study aimed at determination of plasticity of selected grades of hard-deformed aluminium alloys of 5xxx series in terms of parameters characteristic for the process of extrusion. The examinations were carried out for 5083 and 5754 alloys in the torsion test using STD 812 torsion plastometer. Using the empirical tests, the study evaluated yield stress of alloys depending on strain, strain rate and temperature and the results were approximated and mathematical models of rheological properties of the aluminium grades studied were determined within the range of parameters of deformation and temperature.

The paper present the results of physical simulation of the deformation of the two-layered AZ31/eutectic material using the Gleeble 3800 metallurgical processes simulator. The eutectic layer was produced on the AZ31 substrate using thermochemical treatment. The specimens of AZ31 alloy were heat treated in contact with aluminium powder at 445°C in a vacuum furnace. Depending on the heating time, Al-enriched surface layers with a thickness of 400, 700 and 1100 μm were fabricated on a substrate which was characterized by an eutectic structure composed of the Mg17Al12 phase and a solid solution of aluminium in magnesium. In the study, physical simulation of the fabricated two-layered specimens with a varying thickness of the eutectic layer were deformed using the plane strain compression test at various values of strain rates. The testing results have revealed that it is possible to deform the two-layered AZ31/eutectic material at low strain rates and small deformation values.

The article presents results of physical modelling of processes of plastic working of the modified Zr-1%Nb zirconium alloy, obtained using different methods of the plastometric testing. The „Gleeble 3800‚ metallurgical process simulator, a DIL805 A/D dilatometer with a plastometric attachment, and a „Setaram‚ plastometer were used for testing. Based on the obtained testing results, the values of the yield stress and limiting plasticity of the tested alloy were determined for wide ranges of temperature variation (?=20÷950 °?) and strain rate variation (=0.1÷15.0 s-1) under continuous loading conditions. It was found that by using different testing methods, different alloy properties, characteristic for a given plastic working process, could be obtained.

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The paper analyzes the high-temperature plasticity characteristics of 20MnB4 and 30MnB4 with micro-additives, intended for cold upsetting and high-carbon steels C45 and C70 in the "solid phase-liquid" during heating and cooling. The investigation was conducted to determine the plastic formability of the examined alloy under hot plastic working conditions. Experiments were carried out on the simulator Gleeble 3800 with the aim of determining the susceptibility of 20MnB4, 30MnB4, C45 and C70 steels to cracking at high temperature. The nil strength (NST), nil ductility (NDT) and ductility recovery temperatures (DRT), and the fracture toughness factor and the BRT (brittleness temperature range) have been determined. [ABSTRACT FROM AUTHOR]

In the paper the analysis of production of bimetallic bars steel-steel resistant to corrosion by explosive cladding. Method explosive cladding is the affirmed process the receipt the bars plated is characterizing the large strength of bond two different metals. Moreover, in this study, the author presents the bond strength of interface of bimetallic joint of the cross section on the test bar. [ABSTRACT FROM AUTHOR]

The article presents analysis on the results of 171 second-look laparotomy (SLL) and equate survival of patients having advanced ovarian cancer. The study reveals that the survival rate in patients having recurrence after negative SLL was importantly lower equated to patients with microscopic disease. It shows that probable explanation for encouraging prognosis in the group having microscopic disease was early medication of chemotherapy after SLL.

The article presents the results of rheological testing of Al 5754 alloy in series 5xxx, obtained for deformation parameters corresponding to the process of extrusion of large-size sections on presses. The effect of deformation conditions on the variations in yield stress magnitude was determined. Then, using the least squares method., the actual values of the coefficients of the mathematical model describing the rheological properties of the material under investigation were determined, thus obtaining grounds for conducting the model studies of the extrusion process based on numerical methods. [ABSTRACT FROM AUTHOR]

An abstract of the research paper "The ultrasound-measured tumor-free distance ( uTDF) is a valuable predictor of lymph node status in endometrial cancer" by M. Liro and colleagues, presented at the 24th World Congress on Ultrasound in Obstetrics and Gynecology, is presented.

The article reports the results of investigation into variations in the rheological properties of the Zr-1% Nb alloy when deformed under the conditions of physical modelling of the process of multi-stage hot open die forging of ingots. The programme for rheological testing of the alloy was developed based on the simplex planning method. Tests were carried out on a „Gleeble 3800" plastometer. Based on the rheological test results, a new scheme of ingot deformation in forging process was developed and the experimental verification of the model study results was made in industrial conditions. From the obtained results, high effectiveness of the method of determining the thermomechanical conditions as applied to the process of forging zirconium alloy ingots has been found. [ABSTRACT FROM AUTHOR]

This study presents results of the examinations aimed at determination of rheological properties of selected grades of medium and high-carbon steel grades (C45 and C72D). The examinations were carried out for the hot torsion test using STD 812 torsion plastometer. The results of experimental studies were approximated with the function used for determination of yield stress depending on strain, strain rate and temperature. The study allowed for development of mathematical models of rheological properties of steel grades studied in the analysed scope of parameters of strain and temperature. [ABSTRACT FROM AUTHOR]

The article presents results of the research concerning the physical modeling of plastic working of AZ31 magnesium alloy using two research methods. These studies were conducted using a metallurgical process simulator and torsional plastometer. The research was done for temperature range 200 ÷ 400 °C and strain rate from 0,1 to 20,0 s-1, depending on the testing method. The results allow to determine the coefficients in yield equation needed for the numerical research. Moreover the most advantageous temperature - velocity conditions to realize the process of bars rolling in three high skew rolling mill can be determined. [ABSTRACT FROM AUTHOR]

The paper presents the results of physical modelling of the plastic deformation of the two-layered AZ31 - Al alloys. The AZ31 - Al feedstock was produced using the diffusion bonding method. Heating under pressure led to the formation of a continuous layer of the intermetallic phases at the bond interface of AZ31 - Al. A compression test was used to determine the plastic deformation of the two-layered AZ31 - Al alloys. Based on the analysis of the investigation results it has been found that, as the strain rate decreases and temperature increases, the intermetallic phase yields, and a distinct thinning of the intermetallic phase layer has occurred in the zone directly affected by the anvil. [ABSTRACT FROM AUTHOR]