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), K 1c (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.

In this paper, we present the results of experimental tests and numerical calculations for parts of foundry mold devices made by selective laser melting (SLM). The main aim of this research was to compare the heat conduction efficiency of the conformal and the traditional channel arrangement. The infusion spreader with a conformal channel arrangement and the test material were made with an M2 Concept Laser Cusing machine using 1.2709 steel powder. Temperature changes in the spreaders were compared between conventional and conformal cooling channels using finite element method (FEM) calculations. The position of the so-called “thermal equilibrium isotherm” was determined for both sprue spreaders, which separate the area of the mold with a constant temperature from the zone of cyclic temperature changes. The components of the sprue spreaders in a stress state caused by temperature changes during the operation of the pressure machine were determined using the FEM model. It was found that the cooling system shortened the time of solidification and cooling of the alloy. Based on the analysis of the strength test results and the fracture surface of the samples, the relationship between heat treatment parameters and the strength, hardness, and elongation of the tested material was determined. The sprue spreaders were installed under a pressure machine and tested under production conditions. The use of a sprue spreader with a conformal cooling system shortened the time of a single cycle of the casting machine compared to the conventional solution.

This preliminary study characterizes the bronze metalworking on a defensive settlement of the Lusatian culture in former Kamieniec (Chełmno land, Poland) as it is reflected through casting workshop recovered during recent excavations. Among ready products, the ones giving evidence of local metallurgy (e.g. casting moulds and main runners) were also identified. With the shrinkage cavities and dendritic microstructures revealed, the artifacts prove the implementing a casting method by the Lusatian culture metalworkers. The elemental composition indicates application of two main types of bronzes: Cu-Sn and Cu-Pb. Aside these main alloying additions, some natural impurities such as silver, arsenic, antimony and nickel were found which may be attributed to the origin of the ore and casting technology. The collection from Kamieniec was described in terms of its structure and composition. The investigations were made by means of the energy dispersive X-ray fluorescence spectroscopy (ED-XRF), scanning electron microscopy (SEM) coupled with an energy dispersive Xray analysis system (EDS) and optical microscopy (OM). In order to fingerprint either local or non-local profile of the alloys, the ED-XRF data-set was statistically evaluated using a factor analysis (FA).

The research aimed at assessing the influence of alloying elements, such as Al, Si, Ni, Pb and Bi on the chosen alloys of Cu-Zn. Microstructures were examined with the use of optical and scanning microscopy with X-ray microanalysis. The properties of the received alloys were determined with regard to changes in the mechanical parameters, namely R m , A 5 , HB, also, machinability changes were assessed as well as proclivity to hot fracturing of Cu-Zn alloys with additives of lead and bismuth. The results indicate the possibility of obtaining very high mechanical properties: R m up to 700 MPa, hardness within the range of 130-180 HB and A 5 from 3 to 30%. Also, in the case of the researched alloys, the machining and hot fracturing results look promising. StreszczeniePodjęte badania miały na celu określenie oddziaływania dodatków stopowych, takich jak: Al, Si, Ni, Pb i Bi w wybranych stopach Cu-Zn. Przeprowadzono badania mikrostruktur z wykorzystaniem mikroskopii świetlnej oraz mikroskopii skaningowej z mikroanalizą rentgenowską. Określono właściwości otrzymanych stopów pod względem zmian takich parametrów mechanicznych jak: R m , A 5 , HB oraz poddano ocenie zmiany skrawalności i skłonności do pęknięć na gorąco stopów Cu-Zn z dodatkami ołowiu i bizmutu.Otrzymane wyniki wskazują na możliwości uzyskania stopów o bardzo wysokich właściwościach mechanicznych, takich jak: wytrzymałość na rozciąganie do 700 MPa, twardość w zakresie 130-180 HB oraz wydłużenie w zakresie 3-30%. Korzystnie przedstawiają się również wyniki oceny skrawalności oraz pęknięć na gorąco. Słowa kluczowe: stopy Cu-Zn, właściwości mechaniczne, właściwości technologiczne, dodatki stopowe