The aim of this work is to develop a numerical model capable of predicting the grain density in the Mg-based matrix phase of an AZ91/SiC composite, as a function of the total mass fraction of the embedded SiC particles. Based on earlier work in a range of alloy systems, we assume an exponential relationship between the grain density and the maximum supercooling during solidification. Analysis of data from cast samples with different thicknesses, and mass fractions of added SiCp, permits conclusions to be drawn on the role of SiCp in increasing grain density. By fitting the data, an empirical nucleation law is derived that can be used in a micro model. Numerical simulation based on the model can predict the grain density of magnesium alloys containing SiC particles, using the mass fraction of the particles as inputs. These predictions are compared with measured data.

During excavation of the cremation cemetery of urnfield culture in Legnica at Spokojna Street (Lower Silesia, Poland), dated to 1100-700

BC, the largest - so far in Poland – a collection of casting moulds from the Bronze Age was discovered: three moulds for axes casting

made out of stone and five moulds for casting sickles, razors, spearhead and chisels, made out of clay. This archaeological find constituted

fittings of foundrymen’s graves. In order to perform the complete analysis of moulds in respect of their application in the Bronze Age

casting technology analytical methods, as well as, computer aided methods of technological processes were used. Macroscopic

investigations were performed and the X-ray fluorescence spectrometry method was used to analyse the chemical composition and metal

elements content in mould cavities. Moulds were subjected to three-dimensional scanning and due to the reverse engineering the geometry

of castings produced in these moulds were obtained.

The gathered data was used to perform design and research works by means of the MAGMA5

software. Various variants of the pouring

process and alloys solidification in these archaeological moulds were simulated. The obtained results were utilised in the interpretation of

the Bronze Age casting production in stone and clay moulds, with regard to their quality and possibility of casting defects occurrence

being the result of these moulds construction.

The reverse engineering, modelling and computer simulation allowed the analysis of moulds and castings. Investigations of casting moulds

together with their digitalisation and reconstruction of casting technology, confirm the high advancement degree of production processes

in the Bronze Age.

The paper discusses issues related to the technology of melting and processing of copper alloys. An assessment was made of the impact of titanium and iron introduced in the form of pre-alloy - Ti73Fe master alloy on the microstructure and selected properties of pure copper and copper-silicon alloy. There are known examples of the use of titanium and iron additive to the copper alloy. Titanium as an additive introduced to copper alloys to improve their properties is sometimes also applicable. In the first stage of the study, a series of experimental castings were conducted with variable content of Ti73Fe master alloy entering copper in quantities of 5 %, 15 %, 25 % in relation to the mass of the metal charge. In the second stage, a silicon additive was introduced into copper in the amount of about 4 % by weight and 0.5 % and 1 % respectively of the initial Ti73Fe alloy. Thermodynamic phase parameters were modelled using CALPHAD method and Thermo-Calc software, thus obtaining the crystallization characteristics of the test alloys and the percentage of structural components at ambient temperature. Experiments confirmed the validity of the use of Ti73Fe master alloy as an additive. The pre-alloy used showed a favourable performance, both in terms of addition solubility and in the area of improvement of strength properties. Changes were achieved in the microstructure, mainly within the grain, but also in the developed dendrites of the solid solution. Changes occur with the introduction of titanium with iron into copper as well as to two-component silicon bronze.

As part of the studies conducted in the field of broadly understood casting of non-ferrous metals, selected results on the impact of variable additions of copper and silicon in aluminium were presented. A series of melts was carried out with copper content kept constant at a level of 2% (1st stage) and 4% (2nd stage) and variable contents of silicon introduced into aluminium. The crystallization characteristics of the examined alloys and the percentage of structural constituents at ambient temperature were obtained by modelling the thermodynamic parameters of individual phases with the CALPHAD method. The microstructure of the obtained alloys was examined and microhardness was measured by the Vickers-Hanemann method. The alloy properties were assessed based on the results of mechanical tests, including ultimate tensile strength (UTS), hardness (BHN) and elongation (E). The machinability of the tested alloys was analyzed in a machinability test carried out by the Keep-Bauer method, which consisted in drilling with a constant feed force.

The obtained results clearly indicate changes in the images of microstructure, such as the reduction in grain size, solution hardening and precipitation hardening. The changes in the microstructure are also reflected in the results of mechanical properties testing, causing an increase in strength and hardness, and plasticity variations in the range of 4 ÷ 16%, mainly due to the introduced additions of copper and silicon. The process of alloy strengthening is also visible in the results of machinability tests. The plotted curves showing the depth of the hole as a function of time and the images of chips produced during the test indicate an improvement in the wear resistance obtained for the tested group of aluminium alloys with the additions of copper and silicon.