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.
The ecological factor is very important in shaping properties of alloys. It leads to a limitation or elimination, from the surroundings, of harmful elements from the heavy metals group. The so-called eco-brasses group comprises common lead-free brasses containing 10 to 40% of zinc and arsenic brasses of a high dezincification resistance. Among standardized alloys, CW511L alloy ( acc. to EN standard) or MS-60 alloy (acc. to DIN) can be mentioned. Investigations were performed on two different kinds of metal charges: ingots cast by gravity and the ones obtained in the semi-continuous casting technology with using crystallizers. The casting quality was analysed on the basis of the microstructure images and mechanical properties. The investigations also concerned increasing the corrosion resistance of lead-free alloys. This resistance was determined by the dezincification tendency of alloys after the introduction of alloying additions, i.e. aluminium, arsenic and tin. The investigations focused on the fact that not only alloying additions but also the production methods of charge materials are essential for the quality of produced castings. The introduced additions of aluminium and tin in amounts: 0÷1.2 wt% decreased the dezincification tendency, while arsenic, already in the amount of 0.033 wt%, significantly stopped corrosion, limiting the dezincification process of lead-free CuZn37 brass. At higher arsenic contents, corrosion occurs only within the thin surface layer of the casting (20 μ).
Silicon bronzes are characterised by good mechanical properties and by high corrosion and mechanical wear resistance. The process of sleeve casting by means of the centrifugal casting with the horizontal axis of the mould rotation was analysed. The assessment of the influence of modification and centrifugal casting parameters on the microstructure and mechanical properties of alloys was carried out in the hereby work. Zirconium was applied as a modifier. Speed of rotation of the mould was the variable parameter of the centrifugal casting. The investigation results were summarised on the basis of the microstructure analysis and mechanical properties determination: UTS, proof stress, A10 and BHN. The experiment aimed at finding the information in which way the modification together with changing the pouring parameters influence the mechanical properties of the CuSi3Zn3FeMn alloy.
High prices of tin and its limited resources, as well as several valuable properties characterising Cu-Sn alloys, cause searching for materials of similar or better properties at lower production costs. The influence of various nickel additions to CuSn10 casting bronze and to CuSn8 bronze of a decreased tin content was tested. Investigations comprised melting processes and casting of tin bronzes containing various nickel additions (up to 5%). The applied variable conditions of solidification and cooling of castings (metal and ceramic moulds) allowed to assess these alloys sensitivity in forming macro and microstructures. In order to determine the direction of changes in the analysed Cu-Sn-Ni alloys, the metallographic and strength tests were performed. In addition, the solidification character was analysed on the basis of the thermal analysis tests. The obtained results indicated the influence of nickel in the solidification and cooling ways of the analysed alloys (significantly increased temperatures of the solidification beginning along with increased nickel fractions in Cu-Sn alloys) as well as in the microstructure pattern (clearly visible grain size changes). The hardness and tensile strength values were also changed. It was found, that decreasing of the tin content in the analysed bronzes to which approximately 3% of nickel was added, was possible, while maintaining the same ultimate tensile strength (UTS) and hardness (HB) and improved plasticity (A5).
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.
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.
(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 X-ray 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 casting workshop in Grzybiany is one of the most important archaeological sites in regards to casting technology from the Bronze and Early Iron Ages. During the "Grzybiany. Osada nadjeziorna z epoki brązu i żelaza" [Grzybiany. Lakeside settlement from the Bronze and Early Iron Ages] research, the structure of casting moulds was analyzed as well as the chemical composition and microstructure of one of the more-interesting metal artefacts found within the workshop. Based on this, geometric visualization was performed with the help of computer-modeling methods. For scientific, experimental, and educational purposes, reconstruction of a zoomorphic pendant was performed using the lost-wax method. Wax models injected into a matrix were used, along with fired ceramic (gypsum) moulds and a specially prepared modeling alloy that corresponds to the original material. In this way, a true replica of the original was obtained: technologically, structurally and chemically. Studies of production technology of the casting workshop dated back to the Bronze and Early Iron Age help to increase the knowledge of the mould-preparing technology and the alloys used. Modern tools and computer programs aid in the research of old technologies and help disseminate the results.
PL
Pracownia odlewnicza w Grzybianach należy do jednego z najważniejszych stanowisk archeologicznych pod względem studiów nad technologią odlewniczą w epoce brązu i wczesnej epoce żelaza. W toku prac wykonano analizę struktury form odlewniczych. Przeprowadzono także analizę składu chemicznego i mikrostruktury jednego z ciekawszych zabytków metalowych, odkrytych na terenie pracowni. Na tej podstawie, z wykorzystaniem metod modelowania komputerowego, wykonano wizualizację geometryczną. W celach naukowych, doświadczalnych i edukacyjnych wykonano rekonstrukcję zawieszki zoomorficznej przy wykorzystaniu metody wytapianych modeli. Zastosowano modele woskowe wtryskiwane do matrycy, formy ceramiczne (gipsowe) wypalane oraz specjalnie przygotowany stop modelowy, odpowiadający oryginalnemu. W ten sposób uzyskano wierną technologicznie, strukturalnie i chemicznie replikę zabytku. Badania technologii produkcji warsztatu odlewniczego z epoki brązu i wczesnej epoki żelaza przyczyniają się do wzrostu świadomości o stosowanych technikach przygotowania form i wykorzystywanych stopach. Współczesne narzędzia i techniki komputerowe wspomagają badania dawnych technologii i służą ich upowszechnianiu.
The analysis of brasses regarding their microstructure, mechanical properties and ecological characteristics has been presented. The influence of characteristic alloying elements contained in the brasses and the possibilities of replacing them with other elements have been assessed. The paper contains the results of studies on the influence of chosen additional elements shaping the structure and properties of unleaded alloys based on Cu-Zn system as the matrix. The research aimed at determining the mechanism and the intensity of influence of such additives as tellurium and bismuth. The microstructures were investigated with the help of light microscopy and scanning electron microscopy with X-ray microanalysis (SEM-EDS) for determining significant changes of the properties.
PL
Przedstawiono analizę mosiądzów w zakresie mikrostruktury, właściwości wytrzymałościowych oraz charakterystyki ekologicznej. Poddano ocenie wpływ charakterystycznych pierwiastków stopowych zawartych w mosiądzach i możliwości zastąpienia ich innymi. W pracy ujęto wyniki badań wpływu wybranych dodatkowych pierwiastków kształtujących strukturę i właściwości bezołowiowych stopów na osnowie układu Cu-Zn. Podjęte badania miały na celu określenie mechanizmu i intensywności oddziaływania dodatków takich jak: tellur i bizmut. Przeprowadzono badania mikrostruktur z wykorzystaniem mikroskopii świetlnej oraz mikroskopii skaningowej z mikroanalizą rentgenowską SEM-EDS, dla określenia istotnych zmian właściwości.
During the research a group of copper and tin alloys was investigated. The influence of variable additions of aluminium within the range of 0.3 – 1.4 wt % was analysed on tin bronze CuSn10 with the aim of obtaining durable bronzes, from outside the normalized copper alloy groups. Melts were conducted in order to obtain alloy samples for testing the chosen properties. Metallographic and SEM-EDS tests were carried out to determine the microstructure changes caused by introducing Al addition to CuSn10 alloy. Also, chosen mechanical properties were tested for the alloys investigated. The results showed considerable changes in the microstructure as well as significant hardening of the Cu-Sn alloys as the result of aluminium addition. The thermal and dilatometric analysis confirmed the presence of phase changes, also their parameters were assessed depending on the share of aluminium addition in the CuSn10. The aluminium additive applied within the range of 0.3-1.4 wt% to CuSn10 bronze clearly impacted the microstructure and the strength properties analysed, causing the increase in strength and hardness with simultaneous insignificant decrease of elongation of the CuSn10Al alloys.
Arsenical copper has been used since 5th millennium cal.BC, later exchanged by application of Cu-Sn alloys in metallurgy. This work presents the results of metallographic and mechanical properties studies performed on two flat axes connected with local Eneolithic societies (4500-3000 cal.BC). The axes are one of the oldest metal artifacts from Polish land. Originally they were made from Cu-As alloy, and their chemical composition was established by X-ray fluorescence spectroscopy (XRF). Their microstructure was analysed using optical microscopy (OM) and scanning electron microscopy conducted with energy-dispersive X-ray spectroscopy (SEM-EDS). The macrostructure analysis (OM) of the axes was performed as well. On the basis of the results, the alloys used in the Eneolithic to cast the axes were reproduced in lab. In order to achieve the characteristics of the alloys, their mechanical properties including ultimate tensile strenght (UTS), hardness (HB), microhardness (HV0,1) and ductility were examined. The solidification process was studied by means of thermal analysis.
The casting workshop in Grzybiany, in Lower Silesia (SW Poland) is a valuable source of knowledge on the development of casting techniques in the 7 – 6 centuries BC. Abundant evidence found on the archaeological site points to cast manufacturing by means of precision casting in ceramic moulds (lost-wax molding). The workshop is the biggest collection of moulds for bracelet, necklace and other smaller decorative artefacts in Poland. The aim of the work is to conduct the research of the moulds and casts with the view of performing a computer reconstruction of the casting moulds from the Bronze and Early Iron Age, based on the Grzybiany finds. As part of the work, both the microscopic structure and defectoscopic analyses of the casting moulds were performed. Chemical composition of the casts was tested using the X-ray fluorescence spectroscopy method. Based on these results and using computer modelling methods, a geometric visualisation was performed, which is the bases for preparing the visualisation of the process of pouring liquid metal into the moulds, reconstructing both the technology and the alloys used.
The article presents the research results obtained at the Department of Foundry of Non-Ferrous Metals at the Foundry Faculty of AGH, the University of Science and Technology, in Krakow. The research comprises the processes connected with the technology of melting, refining and making casts based on copper matrix, both contemporary and historical, especially bronzes containing tin, zinc and lead. These issues are well-known but they still pose problems for contemporary foundries. The article presents the results of modifying formulas on the improvement of mechanical properties and limiting casting defects.
PL
W artykule przedstawiono wyniki badań realizowanych w Pracowni Odlewnictwa Metali Nieżelaznych na Wydziale Odlewnictwa AGH w Krakowie. Badania obejmują procesy związane z technologią topienia, uszlachetniania oraz odlewania stopów na osnowie miedzi, zarówno współczesnych jak i historycznych, głównie brązów zawierających cynę. cynk i ołów. Poruszone zostały zagadnienia związane z procesem topienia oraz kształtowania struktury odlewów z miedzi. Problemy te znane są już od dawna, ale nadal stanowią aktualny problem współczesnych odlewni. Przedstawione zostały wyniki badań wpływu preparatów o charakterze modyfikującym na poprawę właściwości mechanicznych i ograniczenie wad odlewniczych.
The work presents experiment results from the area of copper casting technology and chosen examples of alloyed copper. At present, copper casting technology is applied in many branches of industrial manufacturing, especially in the sector of construction, communications, arms and power engineering. Alloyed copper, containing slight additions of different elements and having special physio-chemical properties, is used in a special range of applications. Copper technology and alloyed copper analyses have been presented, these materials being used for cast manufacturing for power engineering. The quality of casts has been assessed, based on their microstructure analysis, chemical content and the cast properties. During the research, special deoxidizing and modifying agents were applied for copper and chosen examples of alloyed copper; also exemplary samples were tested with the help of metallographic analysis, electrical conductivity and gaseous impurities research.
W artykule zaprezentowano wyniki badań nad wybraną grupą stopów z układu Cu-Sn. Przeanalizowano oddziaływanie udziału cyny w brązach cynowych w zakresie od 6 do 30 %. Kontynuując badania zmierzające do uzyskania odpornych na zużycie brązów spoza grup znormalizowanych stopów miedzi, oceniono oddziaływanie dodatku aluminium w stopach Cu-Sn. Przeprowadzono badania metalograficzne zmierzające do określenia mechanizmów oddziaływania zmiennych zawartości dodatków stopowych z uwagi na zmiany podstawowych właściwości mechanicznych. Uzyskane wyniki wskazują na wyraźne zmiany mikrostruktur badanych stopów, jak również wykazują silne utwardzenie stopów Cu-Sn. Zastosowane dodatki aluminium w zakresie do 3 % w wybranych stopach powodują również poprawę właściwości mechanicznych badanych brązów cynowych z dodatkiem aluminium.
EN
During the research a chosen group of copper - tin alloys were investigated. The influence Sn in tin bronzes was analysed in the broad spectrum between 6 to 30%. Continuing the research aiming at obtaining durable bronzes outside the normalised copper alloys, the influence of chosen aluminium additive in selected Cu-Sn alloys was assessed. Metallographic tests were carried out to determine the operating mechanisms and also the influence of the varied alloying additives from the perspective of changes in the basic properties of the alloys investigated. The obtained results clearly point to the changes in microstructures and mechanical properties of the alloys investigated.
The cast alloys crystallizing in Fe-C-V system are classified as white cast iron, because all the carbon is bound in vanadium carbides. High vanadium cast iron has a very high abrasion resistance due to hard VC vanadium carbides. However, as opposed to ordinary white cast iron, this material can be treated using conventional machining tools. This article contains the results of the group of Fe-C-V alloys of various microstructure which are been tested metallographic, mechanical using an INSTRON machine and machinability with the method of drilling. The study shows that controlling the proper chemical composition can influence on the type and shape of the crystallized matrix and vanadium carbides. This makes it possible to obtain a high-vanadium cast iron with very high wear resistance while maintaining a good workability.
The research aimed at assessing the influence of alloying elements, such as Al, Si, Ni, Pb and Bi on the chosen alloysof Cu-Zn. Microstructures were examined with the useof 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 Rm, A5, 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: Rm up to 700 MPa, hardness within the range of 130-180 HB and A5 from 3 to 30%. Also, in the case of the researched alloys, the machining and hot fracturing results look promising.
PL
Podjęte 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: Rm, A5, 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.
Many traces of copper metallurgy, such as slag and other copper melts, can be found in the area of Lower Silesia. The tested material mainly consists of copper slag with different content of copper melts, being a semi product. The copper metallurgy remains, discovered during the research, undergo specialistic analyses, which will help better characterise the findings as well as contribute to documenting metallurgical processes in the historical bloomeries in Lower Silesia, and moreover to prepare further research in this field. The material coming from the area of Miedzianka, being the oldest and the longest working exploitation centre of copper ores and pollymetalic ores, is of special significance for the research. Mining activity in the area of Miedzianka took place as early as the beginning of the 14th century, the first record from 1311 (Cuprifodina in montubus) is the oldest information concerning copper mining in Poland.
PL
Dolny Śląsk jest terenem, na którym odnaleziono liczne ślady metalurgii miedzi w postaci żużli i wytopów miedzianych. Badany materiał stanowią głównie żużle miedzi o zróżnicowanej zawartości miedzi i wytopki miedziane, mające charakter półproduktu. Odkryte w czasie badań pozostałości metalurgii miedzi poddawane są specjalistycznym analizom, co pozwala na lepsze scharakteryzowanie znalezisk i przyczyni się do udokumentowania procesów metalurgicznych na terenie historycznie działających hut Dolnego Śląska oraz przygotowania dalszych badań w tym zakresie. Szczególnie istotny dla badań jest materiał metalurgiczny pochodzący z rejonu Miedzianki, będącego najstarszym i najdłużej działającym ośrodkiem eksploatacji rud miedzi i rud polimeta licznych na Dolnym Śląsku. Okręg górniczy w rejonie Miedzianki funkcjonował przynajmniej od początków XIV w., a pierwsza wzmianka na jej temat z 1311 r. (Cuprifodina in montubus) jest najstarszą informacją na temat górnictwa miedzi na terenie Polski.
Technologia wytapianych modeli należy do najstarszych technologii odlewniczych. Historycznie służyła do odlewania narzędzi, broni i ozdób. Model wykonany z wosku pszczelego oblepiano gliną suszono i wypalano. Otrzymywano odlewy o dużej gładkości powierzchni, dokładności i precyzji wykonania ornamentu. Metodą tą odlewano niewielkie kilkugramowe odlewy jak i wielkogabarytowe pomniki. Współcześnie ta technologia jest wykorzystywana w wielu ważnych gałęziach produkcji zarówno artystycznej, jak i przemysłowej. Szczególnie w przemyśle zbrojeniowym, lotniczym, motoryzacyjnym, energetycznym, budowlanym, a nawet kosmicznym. W pracy przedstawiono wyniki badań i eksperymentów, prowadzonych w zakresie technologii odlewnictwa miedzi i stopów miedzi z zastosowaniem metody wytapianych modeli, zarówno w aspekcie historycznym, jak i współczesnej praktyki przemysłowej. Przykładowo przedstawiono analizę wybranych elementów dawnych technologii, form i odlewów wytworzonych w epoce brązu oraz wyniki badań dotyczące aktualnie produkowanych odlewów dla branży energetycznej. Jakość odlewów została oceniona na podstawie przeprowadzonych badań z zakresu mikrostruktury, składu chemicznego, przewodności elektrycznej i zawartości tlenu.
EN
Investment casting technology belongs to the oldest casting techniques. Historically, it was used for casting tools, weapons and ornaments. A model, made from beeswax, was covered in loam, dried and fired. The casts obtained were characterised by high surface smoothness, accuracy and precision of its ornaments. This method was used for relatively small casts as well as for big monuments. Nowadays, this technology is used in many fields of manufacturing, both artistic and industrial, especially in ornaments, aviation, automotive, power, construction and even space industry. This work presents the results of research and experiments conducted in the field of casting technology of copper and copper alloys, applying the investment casting method, both in its historical aspect and modern industrial practice. An exemplary analysis was presented of the chosen elements of the old technologies, moulds and casts, as well as the results of casts made currently for the power industry. The casts quality was evaluated based on the research of their microstructure, chemical composition, electrical conductivity and oxygen content.
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