S. Sawicki

Application of Torsion Test for Determination of Rheological Properties of 5019 Aluminium Alloy

The paper presents the results of the study aimed at determination of plasticity of hard-deformed aluminium alloy grade 5019 in terms of parameters characteristic for the process of extrusion. The examinations were carried out in hot torsion test. Using the developed mathematical model of the analyzed alloy the mathematical modelling of torsion test was also performed.

Structure and mechanism of the deformation of Grade 2 titanium in plastometric studies

ABSTRACT In this paper, the results of plastometric and material studies on grade 2 titanium are presented. Cylindrical titanium samples were compressed at elevated temperatures on a Gleeble thermo-mechanical simulator. The process was captured in the form of stress-strain diagrams. Then, for the chosen-deformed samples, structural studies were performed on a digital light microscope. On the basis of the results, it was possible to determine the plastometric processing conditions that are most suitable for the fragmentation of the grains of the tested titanium. In order to find optimal processing parameters, it was also important to describe the plastometric process through the appropriate constitutive equations. Material constants in this equation were determined on the basis of a hyperbolic sinusoidal equation. This paper is part of a thematic issue on Titanium.

Plastometric Testing of Rheological Properties of 5083 and 5754 Aluminium Alloy

The paper present a method for determining the real steel work-hardening curves based on the cylindrical specimen compression test. The subject of testing were 5083 and 5754 aluminium alloy. The tests were carried out using the physical simulator of metallurgical processes GLEEBLE 3800 (Figure 1a) for the temperature range of 400 ÷ 560 °C and the strain rate range of 0,1 - 1,0s-1. Based on plastic deformation parameters recorded during the experiment, mathematical processing, that is the digital filtration and approximation of the obtained testing results, will be performed. Then, using the inverse method, the actual values of the coefficients of the numerical models for the rheological properties of the tested materials will be determined.

Physical Simulations of the Controlled Rolling Process of Experimental Steels with Modified Chemical Composition Allocated to Pipelines

The research presented in the paper was carried out for the experimental steels with modified chemical composition allocated to pipelines for 760÷1180 °C range, strain rate s–1 s–1 and different distributions of particular reductions between passes were presented. Physical modeling of the rolling process was carried out upon using the GLEEBLE 3800 simulator. The research was based on the findings of the paper [1].

Metallographic Analysis of Bimetallic Ribbed Bars Produced from Feedstock Mill of the Surfacing Method TIG and of the Method ESS LM Received

A considerable increase in interest in using corrosion resistant steel clad ribbed bars in the construction industry has been observed in recent years. This is owing to the particular properties of these bars, namely high durability and rigidity, good mechanical properties, and high corrosion resistance. Bimetallic ribbed bars can be manufactured in medium-size and small shape mills from previously produced bimetallic feedstock. The manufacture of ribbed bars with an outer layer of corrosion-resistant steel is a complicated process that involves numerous technological problems. The most important of which include the obtaining of bimetallic feedstock with the adequate strength of the bond in the region of junction between the core and the clad layer, and assuring the even plastic flow of both bimetallic layers during the process of rolling in the elongating and forming passes in the shape Mill. Failure to meet these conditions may result in a delamination of the bimetallic band during rolling or the formation of other defects, which will disqualify the finished bimetallic bar [1÷4]. In the paper the metallographic analysis of bimetallic ribbed bars steel-steel resistant to corrosion produced from bimetallic feedstock mill of the surfacing method TIG and of the method ESS LM received. Surfacing method TIG and ESS LM method are the affirmed processes the receipt the bars plated is characterizing the large strength of bond two different metals. Moreover, in this study, the authors present the bond strength of interface of bimetallic joint of the cross section on the test bar. The core was of the constructional carbon steel C45E and the clad layer was made of the corrosion resistant steel X2CrNi18-10. Plastometric tests were performed on a Gleeble 3800 plastometer owned by the Institute of Modelling and Automation of Plastic Working Processes, using strain rates of 0.1 s-1, 1.0 s-1 and 10 s-1 respectively [1÷3, 7].