Currently there is a constant development in the field of aluminium alloys engineering. This results from, i.a., better understanding of the
mechanisms that direct strengthening of these alloys and the role of microalloying. Now it is microalloying in aluminum alloys that is
receiving a lot of attention. It affects substantially the macro- and microstructure and kinetics of phase transformation influencing the
properties during production and its exploitation. 7xxx series aluminum alloys, based on the Al-Zn-Mg-Cu system, are high-strength
alloys, moreover, the presence of Zr and Sr further increases their strength and improves resistance to cracking.
This study aims to present the changes of the properties, depending on the alloy chemical composition and the macro- and microstructure.
Therefore, the characteristics in the field of hardness, tensile strength, yield strength and elongation are shown on selected examples.
Observations were made on ingot samples obtained by semi-continuous casting, in the homogenized state.
Samples were prepared from aluminum alloys in accordance with PN-EN 573-3: 2013. The advantage of Al-Zn-Mg-Cu alloys are
undoubtedly good strength, Light-weight and resistance to corrosion. As widening of the already published studies it is sought to
demonstrate the repeatability of the physical parameters in the whole volume of the sample.
Issues connected with high quality casting alloys are important for responsible construction elements working in hard conditions.
Traditionally, the quality of aluminium casting alloy refers to such microstructure properties as the presence of inclusions and intermetallic
phases or porosity. At present, in most cases, Quality index refers to the level of mechanical properties – especially strength parameters,
e.g.: UTS, YS, HB, E (Young’s Modulus), K1c (stress intensity factor). Quality indexes are often presented as a function of density.
However, generally it is known, that operating durability of construction elements depends both on the strength and plastic of the material.
Therefore, for several years now, in specialist literature, the concept of quality index (QI) was present, combines these two important
qualities of construction material. The work presents the results of QI research for casting hypoeutectic silumin type EN AC-42100
(EN AC-AlSi7Mg0.3), depending on different variants of heat treatment, including jet cooling during solution treatment.
The research focuses on assessing the metal content, mainly copper, lead, iron and also silver in metallurgical slag samples from the area
where historical metallurgical industry functioned. In the smelter located in Mogiła, near Krakow (southern Poland), whose operation is
confirmed in sources from 1469, copper was probably refined as well as silver was separated from copper. Based on the change of
chemical and soil phase content and also taking cartographic and historical data into account, considering the restrictions resulting from
the modern land use the area was determined whose geochemical mapping can point to the location of the 15th century Jan Thurzo’s
smelter in Mogiła near Krakow. Moreover, using the same approach with the samples of this kind here as with hazardous waste, an
attempt has been made to assess their impact on the environment. Thereby, taking the geoenvironmental conditions into account, potential
impact of the industrial activity has been assessed, which probably left large scale changes in the substratum, manifested in the structure,
chemical content and soil phase changes. Discovering areas which are contaminated above the standard value can help to identify
historical human activities, and finding the context in artefacts allows to treat geochemical anomalies as a geochronological marker. For
this purpose the best are bed sediments, at present buried in the ground, of historical ditches draining the area of the supposed smelter.
Correlating their qualities with analogical research of archeologically identified slags and other waste material allows for reconstructing
the anthropopressure stages and the evaluation of their effects. The operation of Jan Thurzo’s smelter is significant for the history of
mining and metallurgy of Poland and Central and Eastern Europe.
Cast axes are one of the most numerous categories of bronze products from earlier phases of the Bronze Age found in Poland. They had multiple applications since they were not only used objects such as tools or weapons but also played the prestigious and cult roles.
Investigations of the selected axes from the bronze products treasure of the Bronze Age, found in the territory of Poland, are presented
in the hereby paper. The holder of these findings is the State Archaeological Museum in Warsaw. Metallurgical investigations of axes with bushing were performed in respect of the casting technology and quality of obtained castings. Macroscopic observations allowed to document the remains of the gating system and to assess the range and kind of casting defects. Light microscopy revealed the microstructure character of these relicts. The chemical composition was determined by means of the X-ray fluorescence method with energy dispersion (ED-XRF) and by the scanning electron microscopy with X-ray energy dispersion analysis in micro-areas (SEM-EDS). The shape and dimensions of cores, reproducing inner parts of axes were identified on the basis of the X-ray tomography images. Studies reconstructed production technology of the mould with gating system, determined chemical composition of the applied alloys and casting structures as well as revealed the casting defects being the result of construction and usage of moulds and cores.
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 casting workshop was discovered with numerous artifacts, confirming the existence of the manufacturing process of metal ornaments using ceramic molds and investment casting technology in Lower Silesia (Poland) in 7-6 BC. The research has yielded significant technological information about the bronze casting field, especially the alloys that were used and the artifacts that were made from them. Based on the analyses, the model alloys were experimentally reconstructed. Taking advantage of the computer-modeling method, a geometric visualization of the bronze bracelets was performed; subsequently, we simulated pouring liquid metal in the ceramic molds and observed the alloy solidification. These steps made it possible to better understand the casting processes from the perspective of the mold technology as well as the melting and casting of alloys.