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EN
The present work discusses results of increased temperature on shape-dimensional changes of a 110 type hose coupling, produced from EN AC-AlSi11 alloy with the use of pressure die casting technology. The castings were soaked for 3.5 h at temperatures 460°C, 475°C and 490°C. The verification of shape-dimensional accuracy of the elements after soaking treatment, in relation to raw casting, was carried out by comparing the 3D models received from 3D scanning. Soaking temperature of about 460°C-475°C results in no significant changes in the shapes and dimensions of the castings, or surface defects in the form of blisters, which can be seen at a temperature of 490°C.
PL
W artykule zaprezentowano wyniki badań wpływu różnych wariantów obróbki cieplnej na właściwości mechaniczne dwóch stopów: EN AC-45000 (AlSi6Cu4) i AlSi17CuNiMg, które poddano wyżarzaniu ujednorodniającemu, utwardzaniu dyspersyjnemu oraz obróbce polegającej na połączeniu tych dwóch zabiegów. Badania właściwości mechanicznych przeprowadzono na znormalizowanych próbkach odlanych w koliach. Ujednorodnianie znacząco wpłynęło na poprawę plastyczności stopu w porównaniu do stopu wyjściowego, dlatego przeprowadzono je przed utwardzaniem dyspersyjnym. Pozwoliło to na uzyskanie wzrostu wydłużenia badanych stopów przy zachowaniu bardzo dobrych właściwości wytrzymałościowych (wytrzymałości na rozciąganie Rm i twardości HB) w odniesieniu do stopu po standardowej obróbce T6 (przesycaniu i sztucznym starzeniu). Ponadto przeprowadzona obróbka cieplna wpłynęła pozytywnie na postać wydzieleń krzemu powodując ich rozdrobnienie, częściową sferoidyzację i koagulację.
EN
In the paper are presented results of a research work concerning effects of various variants of heat treatment operations on mechanical properties of the EN AC-45000 (AlSi6Cu4) and AlSi17CuNiMg alloys, after homogenizing treatment, after dispersion hardening treatment, and after treatment consisting in combination of these two mentioned earlier treatments. Tests of the mechanical properties were performed on standardized specimens poured in metal moulds. The homogenizing had a significant effect on improvement of plasticity of the alloy, comparing to raw alloy, and therefore such treatment was performed before dispersion hardening, what enabled obtainment of increased elongation of the investigated alloys, maintaining very good mechanical properties (tensile strength Rm and hardness HB), referring to the alloy after standard T6 treatment (solution and artificial ageing treatment). Moreover, performed heat treatment had advantageous effect on shape of silicon precipitations, resulting in refining, partial spheroidizing and coagulation of the silicon precipitations.
EN
The present work discusses results of preliminary tests concerning the technology of continuous dosage of sodium to a metallic bath from the aspect of modification of EN AC-44200 alloy, through the use of a multiple compound (salt) of sodium. The technology consists in continuous electrolysis of sodium salts occurring directly in a crucible with liquid alloy. As a measure of the degree of alloy modification over the course of testing, the ultimate tensile strength (UTS or Rm) and analysis of microstructure are taken, which confirm the obtained effects of the modification on the investigated alloy. Assurance of stable parameters during the process of continuous modification with sodium, taking into consideration the fact of complex physical-chemical phenomena, requires additional tests aimed at their optimization and determination of a possibility of implementation of such technology in metallurgical processes.
PL
W artykule przedstawiono badania dotyczące możliwości zwiększenia plastyczności okołoeutektycznego stopu AlSi11 przez zastosowanie wyżarzania zmiękczającego. Dla dwóch przyjętych wielkości wejściowych, tj. temperatury i czasu wygrzewania, w oparciu o trójwartościowy plan przeprowadzono badania pozwalające na przedstawienie zmian wytrzymałości na rozciąganie (Rm) oraz wydłużenia (A5) w zależności od parametrów wyżarzania zmiękczającego (temperatury z przedziału 280°C do 370°C i czasu od 2 godzin do 8 godzin). Dla średnich wartości z przyjętych zakresów temperatury i czasu uzyskano wzrost wydłużenia A5 o około 40% w odniesieniu do wartości wyjściowej. Największy wzrost A5 wyniósł 96%, w porównaniu do stopu wyjściowego, dla wygrzewania w temperaturze 370°C przez 8 godzin, równocześnie nieznacznie spadła wytrzymałość Rm, w granicach 15%.
EN
The paper presents research on the possibility of improving the plasticity of near-eutectic AlSi11 alloy by the use of soft annealing treatment. For two assumed input quantities, i.e. temperature and duration of the soaking treatment, based on the trivalent testing plan, have enabled the presentation of changing tensile strength (Rm) and elongation (A5) in function of the soft annealing parameters (temperature in the range from 280°C to 370°C and time from 2 hours to 8 hours). For average values of assumed range of temperature and time there was an increase in elongation (A5) of about 40% compared to the starting value. The highest increase in elongation (A5) amounted to 96%, compared to the initial alloy, which was obtained in the case of the soaking treatment at temperature 370°C for 8 hours, the tensile strength (Rm) decreased simultaneously within limits of 15%.
EN
Very well-known advantages of aluminum alloys, such as low mass, good mechanical properties, corrosion resistance, machining-ability, high recycling potential and low cost are considered as a driving force for their development, i.e. implementation in new applications as early as in stage of structural design, as well as in development of new technological solutions. Mechanical and technological properties of the castings made from the 3xx.x group of alloys depend mainly on correctly performed processes of melting and casting, design of a mould and cast element, and a possible heat treatment. The subject-matter of this paper is elaboration of a diagrams and dependencies between parameters of dispersion hardening (temperatures and times of solutioning and ageing treatments) and mechanical properties obtained after heat treatment of the 356.0 (EN AC AlSi7Mg) alloy, enabling full control of dispersion hardening process to programming and obtaining a certain technological quality of the alloy in terms of its mechanical properties after performed heat treatments. Obtained results of the investigations have enabled obtainment of a dependencies depicting effect of parameters of the solutioning and ageing treatments on the mechanical properties (Rm, A5 and KC impact strength) of the investigated alloy. Spatial diagrams elaborated on the basis of these dependencies enable us to determine tendencies of changes of the mechanical properties of the 356.0 alloy in complete analyzed range of temperature and duration of the solutioning and ageing operations.
EN
Growing market demand, more and more efficient and cleaner vehicles create a challenge for automotive industry. Properties of aluminum, such as: high strength stiffness to weight ratio, high fluidity and castability, easy machinability and weldability and good corrosion resistance make them ideal candidate to replacement of a heavier materials used in vehicles, and the same, have direct effect on fuel consumption. Comparing to steel, titanium or carbon fibers, aluminum alloys are characterized by low impact strength, which can be improved by a heat treatment. In this study one investigated the effect of the heat treatment (natural ageing) on the EN AC-AlSi9Cu3(Fe) alloy modified with strontium. Solution heat treatment temperature’s ranges were selected on the base of heating (melting) curves recorded with use of the thermal derivative analysis (ATD) method. Temperatures of the solution heat treatment were 495°C, 510°C, and 525°C ± 5°C, while the solutioning time ranged from 15 to 105 minutes (15; 60 and 105 min.). Time of the ageing amounted to 1, 3 and 7 days. To determine impact strength of the alloy after performed heat treatment one implemented simplified Charpy test. Maximal values of the impact strength (9,6 J/cm2) were obtained for solutioning temperature 510°C and solutioning time 15 minutes, after seven days of ageing. Obtained results enabled determination of solutioning parameters, which allow obtainment of increased impact strength of the investigation alloy for the T4 heat treatment.
EN
Among non-ferrous alloys, the aluminum alloys have found the most widespread applications within foundry industry. Hypoeutectic silumin of the AlSi9Mg grade is commonly used for large, heavy duty machinery castings with complicated shape and high strength. From technical point of view, tendency to creation of coarse structure can be considered as a drawback of such alloy, what can have adverse effect on properties of the alloy. To obtain optimal structure of the castings and to assure improvement of their mechanical properties, the most effective treatment to perform is modification. Quality of performed modification treatment depends on proper dosing of inoculant and maintaining suitable temperature and time of keeping the alloy before pouring. In the paper are presented test results of crystallization course of refined and modified silumin of the EN AC–43300 (AlSi9Mg) grade, used in castings of pump casings. It has been determined an effect of performed processes of refining and modification on the mechanical properties (Rm, A5, HB and KCV), additionally, metallurgical tests of the alloy have been performed. Basing on analysis of obtained results, the most advantageous modification variant, which is suitable for castings of pump casings and complying with requirements of customers, has been selected.
EN
The Al-Si-Cu alloys with content of the copper from 2 to 4 percent, after solutioning and artificial ageing treatments (T6 heat treatment), feature high strength and very high hardness, however their elongation is considerably reduced. Maintaining value of elongation on the level of initial alloy is possible due to homogenizing treatment performed prior the T6 treatment. Performed strength tests of the initial alloy and the alloy after individual types of the heat treatment enable comparison of obtained results and assessment of usability of the investigated alloy to production of a castings. Test pieces to the strength tests were poured in standardized metal moulds. Parameters of the heat treatment, temperature and duration of heating were established on base of the literature and the ATD diagram performed for the investigated alloy. Investigated EN AC-AlSi6Cu4 alloy after homogenizing treatment becomes plastic, its elongation A5 and its impact strength KC increase nearly three times, with slight decrease of the tensile strength Rm. Dispersion hardening in connection with the homogenizing treatment results in increase of the tensile strength Rm with 68%, hardness and impact strength with 40% with elongation at level of the alloy without heat treatment. Making suitable selection of various types of the heat treatment it is possible, depending on needs, to control mechanical properties of the alloy.
PL
Podjęto działania w zakresie wykonania odlewu artystycznego, to jest medalu 65-lecia Instytutu Odlewnictwa - z wykorzystaniem techniki szybkiego prototypowania. Opisano najważniejsze operacje technologiczne procesu od rysunku 2D do gotowego wyrobu. Wykazano, że teza postawiona w pracy - jest możliwa do realizacji według najnowocześniejszych rozwiązań stosowanych w technologii odlewniczej.
EN
Steps have been taken to make an art casting - a medal commemorating the 65th Anniversary of the establishment of the Foundry Research Institute in Cracow, using a rapid prototyping technique. The most important technological operations from a 2D drawing to the finished product were described. It has been shown that the argument put in the study can be brought into effect using the most modern solutions of foundry technology.
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