|Krzysztof Jaśkowiec, Magdalena Bacior, Małgorzata Grudzień-Rakoczy, Zenon Pirowski, Adam Bitka|
The paper presents the results of investigations of two cast steel grades (further referred to as Alloy 1 and Alloy 2). Alloy 1 contains, among others, 0.25% C, 11.5% Al, 5.85% Cr, 1.97% Mo, in Alloy 2 was obtained 0.035% C, 13.5% Al, elements such as Cr, Ni , Sb, B, did not exceed 1% share in the chemical composition of this alloy. Resistivity tests of Alloy 1 were carried out during the test of resistance to thermal fatigue, while Alloy 2 was tested on a prepared test stand and the resistance was measured using a four-point method.
For Alloy 1, the resistance was measured as a function of time, elongation and temperature. For comparison, the results of tests of other alloys conducted on this stand within the framework of other R&D works are presented.
Using the material obtained during the test for castability of Alloy 2, the influence of solidification conditions on resistivity was determined. The results of calorimetric tests of this alloy are presented, determining the phase transition temperature for various solidification conditions of Alloy 2.
Keywords: resistivity, electrical resistance, aluminium cast steel, elongation,
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Małgorzata Warmuzek, Adelajda Polkowska
This study includes the results of tests related to selecting the data collection parameters for EBSD analysis, correction and modification of the EBS diffraction patterns, and use of selected functionalities of the commercial OIM system. The study also shows the local misorientation range and the local relationships of the crystal lattice orientation at interfaces and grain boundaries, estimated in the polyphase microregions of selected AlFeMnSi alloys.
Keywords: intermetallic phase, crystal lattice, elementary cell, crystallographic orientation, SEM, EBSD,
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Adam Tchórz, Izabela Krzak, Marzanna Książek
This study presents the possibility of using x-ray computed tomography (CT) for the technological quality assessment of multi-layer ceramic moulds used in the precision casting process. Testing concepts were presented with regard to the detection and visualisation of specific internal discontinuities in the structure of ceramic moulds and the determination of their nature. Tomographic recording based on 2D and 3D images enabled the identification of internal discontinuities in ceramic moulds with regards to delamination or porosity with the determination of the percentage of their count, volume and pore shape. The tests were performed for two different ceramic moulds (molochite and quartz) made with the melted models method.
Keywords: x-ray computed tomography, ceramic moulds, precision foundry,
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Emilia Wildhirt, Tomasz Olejnik, Jarosław Jakubski
Testing the properties of mould and core sands are specified in the norms and standards, which are used to determine the suitability of the sand for specific applications. However, the testing of protective coatings for moulding and core sands varies greatly, features multiple areas of interest, and remains to be systematized. The individual character of the existing solutions for the testing and selection of the parameters as well as the selection of suitable test methods for specific coatings are complicated processes. This is due to the high number of factors to be assessed in terms of their applicability to different metals as well as moulding and core sands. This paper describes the results of testing the abrasibility of sand mixes with different thicknesses of protective coatings applied, for different solvents and numbers of coating layers. The adhesion of each coatings was also tested.
Keywords: moulding sands, protective coatings, abrasibility, coating adhesion,
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