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1

Crystallization of the Structural Components of Multiple Remelted AlSi9Cu3 Alloy

Matejka M., Bolibruchova D., Kuriš M.

Archives of Foundry Engineering

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2021

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Vol. 21, iss. 2

41--45

EN

At present, Al-Si-Cu based alloys (with a typical representative AlSi9Cu3 alloy) represent more than half of the castings used in various industries (automotive, aerospace and electrical engineering). These are most often sub-eutectic (exceptionally eutectic) alloys with a content of 6 to 13 wt. % Si and 1 to 5 wt. % Cu. The aim of the paper is to point out the importance of the evaluation of input raw materials that determines the overall properties of the casting and the costs invested in its production. A negative impact on performance can be expected when using an alloy made up of a high proportion of recycled material, despite its economic benefits. Experimental alloys were evaluated based on the results of crystallization process and a combination of scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), and deep etching. The effect of remelting and increasing the remelted returnable material in the batch was manifested especially in the crystallization of iron-rich phases. The negative effect of remelting on the structural components was manifested after the fourth remelting. Gradual increase of remelted returnable material in the batch causes harmful changes in the crystallization process.

2

Study of AlSi9Cu3 Alloy Crystallization Process with Increased Iron Content at Different Number of Remelts

Matejka M., Bolibruchova D., Kasińska J., Kuriš M.

Archives of Foundry Engineering

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2020

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Vol. 20, iss. 1

79--83

EN

Monitoring the solidification process is of great importance for understanding the quality of the melt, for controlling it, and for predicting the true properties of the alloy. Solidification is accompanied by the development of heat, the magnitude of which depends on the different phases occurring during solidification. Thermal analysis is now an important part of and tool for quality control, especially when using secondary aluminium alloys in the automotive industry. The effect of remelting on the change of crystallization of individual structural components of experimental AlSi9Cu3 alloy was determined by evaluation of cooling curves and their first derivatives. Structural analysis was evaluated using a scanning electron microscope. The effect of remelting was manifested especially in nucleation of phases rich in iron and copper. An increasing number of remelts had a negative effect after the fourth remelting, when harmful iron phases appeared in the structure in much larger dimensions.

3

Identification and Analysis of Intermetallic Phases in Age-Hardened Recycled AlSi9Cu3 Cast Alloy

Hurtalová L., Tillová E., Chalupová M.

Archive of Mechanical Engineering

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2012

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Vol. LIX, nr 4

385--396

EN

Purpose: The influence of age-hardening solution treatment at temperature 515 degrees centigrade with holding time 4 hours, water quenching at 40 degrees centigrade and artificial aging by different temperature 130, 150, 170 and 210 degrees centigrade with different holding time 2, 4, 8, 16 and 32 hours on changes in morphology of Fe-rich Al15(FeMn)3Si2 and Cu-rich (Al2Cu, Al-Al2Cu-Si) intermetallic phases in recycled AlSi9Cu3 cast alloy. Material/Methods: Recycled (secondary) AlSi9Cu3 cast alloy is used especially in automotive industry (dynamic exposed cast, engine parts, cylinder heads, pistons and so on). Microstructure was observed using a combination of different analytical techniques (scanning electron microscopy upon standard and deep etching and energy dispersive X-ray analysis – EDX) which have been used for the identification of the various phases. Quantitative study of changes in morphology of phases was carried out using Image Analyzer software NIS-Elements. The mechanical properties (Brinell hardness and tensile strength) were measured in line with STN EN ISO. Results/Conclusion: Age-hardening led to changes in microstructure include the spheroidization of eutectic silicon, gradual disintegration, shortening and thinning of Fe-rich intermetallic phases and Al-Al2Cu-Si phases were fragmented, dissolved and redistributed within alpha-matrix. These changes led to increase in the hardness and tensile strength in the alloy.

PL

Cel: Badanie wpływu utwardzania przez starzenie przesycanie w temperaturze 515 stopni Celsjusza z czasem przetrzymywania 4 godz., hartowanie wodne w 40 stopniach Celsjusza, starzenie przyspieszone w różnych temperaturach: 130, 150, 170 i 210 stopni Celsjusza, przy czasach przetrzymywania: 2, 4, 8, 16 i 32 godziny na zmiany w morfologii stopów odlewniczych AlSi9Cu3 z recyklingu wzbogaconych żelazem (Al15(FeMn)3Si2) lub miedzią (Al2Cu, Al-Al2Cu-Si). Materiał i metody: Pochodzący z recyklingu (wtórny) stop odlewniczy aluminium AlSi9Cu3 jest powszechnie używany, zwłaszcza w przemyśle motoryzacyjnym (dynamiczne, odkryte odlewy, części silnika, głowice cylindrów, tłoki itp.). Mikrostrukturę odlewów badano stosując kombinację różnych technik analitycznych (elektronowa mikroskopia skaningowa w połączeniu z analizą rentgenowską z dyspersją energii (EDX), standardową i z głebokim wytrawianiem), co pozwoliło identyfikować różne fazy międzymetaliczne. Ocena ilościowa zmian w morfologii tych faz została przeprowadzona przy wykorzystaniu oprogramowania analizatora obrazów (Image Analyzer NIS-Elements). Właściwości mechaniczne (twardość w skali Brinella i wytrzymałość na rozciaganie) były mierzone zgodnie z normą STN EN ISO. Wyniki i wnioski: Utwardzanie przez starzenie prowadzi do zmian w mikrostrukturze, które polegają na sferoidyzacji krzemu eutektycznego, stopniowej dezintegracji, skracaniu i ścienianiu faz międzymetalicznych wzbogaconych żelazem. Fazy Al-Al2Cu-Si podlegały fragmentacji, zostały rozpuszczone i redystrybuowane w osnowie stopu. Zmiany te prowadzą do wzrostu twardości stopu i jego wytrzymałości na rozciąganie.

4

Structure analysis of Al cast alloy

Dobrzański L. A., Krupiński M., Krupińska B.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 27, nr 1

23-26

EN

Purpose: The developed design methodologies both the material and technological ones will make it possible to improve shortly the quality of materials from the light alloys in the technological process, and the automatic process flow correction will make the production cost reduction possible, and - first of all-to reduce the amount of the waste products. Design/methodology/approach: Castings were analysed in the paper of car engine blocks and heads from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type fabricated with the "Cosworth" technological process. In this work the AC-AlSi7Cu3Mg alloy structure was investigated, of this alloy samples were cut of for structure analysis of the cylinder part as well of crankshaft of a fuel engine. The investigation show a difference in the (phase) structure morphology as a result of cast cooling rate. Findings: On the quality of casting has influence the walls thickness of car engine elements. Practical implications: In the metal casting industry, an improvement of component quality depends mainly on better control over the production parameters. Originality/value: The value of the applied methodology was to correct identify the casting effects that occurred during the casting process.

5

Methodology of automatic quality control of aluminium castings

Dobrzański L. A., Krupiński M., Sokolowski J. H.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

69-78

EN

Purpose: Employment of the artificial intelligence tools for development of the methodology of the automated assessment of quality and structural defects in the Al and Mg alloys and the custom made computer software will make it possible to determine the quality of the manufactured element based on the digital images registered in the X-ray flow detection examinations. The possibility to correlate the frequency and morphology of defects with the technological process parameters will make it also possible to identify and classify these defects and control the process to minimise and eliminate them. Design/methodology/approach: The developed design methodologies both the material and technological ones will make it possible to improve shortly the quality of materials from the light alloys in the technological process, and the automatic process flow correction will make the production cost reduction possible, and - first of all - to reduce the amount of the waste products. Findings: The merit of the project consists in the interdisciplinary joining of the knowledge in the area of light metal alloys, including Al and/or Mg, in the area of materials processing connected with the entire scope of problems connected with manufacturing of products and their elements, in the area of the automated low-pressure die casting, and also in the methodology of structure and properties assessment of the engineering materials with, among others, the X-ray flaw detection and computer image analysis methods. Practical implications: The developed methodology of the automated assessment of quality and properties of the light Al and Mg based alloys may used by manufacturers of subassemblies and elements of engines (e.g., car engine bodies made from the light alloys with the low-pressure casting in the sand moulds). Originality/value: The project's effects will be shortening the time needed for analyses and elimination of manu subjective evaluation errors made by humans.

6

Computer aided method for quality control of automotive Al-Si-Cu cast components

Dobrzański L. A., Krupiński M., Maniara R., Sokolowski J. H.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 24, nr 2

151-154

EN

Purpose: The technological progress in material engineering causes the continuous need to develop product testing methods providing comprehensive quality evaluation. In material engineering it is the images obtained by various methods that have become the source of information about materials. Design/methodology/approach: The presented methodology, making it possible to determine the types and classes of defects developed during casting the elements from aluminium alloys, making use photos obtained with the flaw detection method with the X-ray radiation. The tests indicate to the applicability of neural networks for this task. It is very important to prepare the neural network data in the appropriate way, including their standardization, carrying out the proper image analysis and correct selection and calculation of the geometrical coefficients of flaws in the X-ray images. Findings: In classical computer algorithms even a slight rotation or change in lighting can binder the proper interpretation and alternation of variable input data. To eliminate this hindrance the programming can be converted by specifying such features of the structure element that remain most significant and effect the similarities of the analysed images. In neural networks this particular feature needs not to be specified - if necessary, the neural network spots it automatically. Practical implications: The computer aided methodology of the quality control of the light Al and Mg based alloys may be used by manufacturers of subassemblies and elements of car engines. Originality/value: The value of the applied methodology was to correct identify the casting effects that occurred during the casting process.

7

Quality analysis of the Al-Si-Cu alloy castings

Dobrzański L. A., Krupiński M., Maniara R., Sokolowski J. H.

Archives of Foundry Engineering

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2007

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Vol. 7, iss. 2

91-94

EN

The developed design methodologies both the material and technological ones will make it possible to improve shortly the quality of materials from the light alloys in the technological process, and the automatic process flow correction will make the production cost reduction possible, and - first of all - to reduce the amount of the waste products. Method was developed for analysis of the casting defects images obtained with the X-ray detector analysis of the elements made from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type as well as the method for classification of casting defects using the artificial intelligence tools, including the neural networks; the developed method was implemented as software programs for quality control. Castings were analysed in the paper of car engine blocks and heads from the Al-Si-Cu alloys of the AC-AlSi7Cu3Mg type fabricated with the "Cosworth" technological process. The computer system, in which the artificial neural networks as well as the automatic image analysis methods were used makes automatic classification possible of defects occurring in castings from the Al-Si-Cu alloys, assisting and automating in this way the decisions about rejection of castings which do not meet the defined quality requirements, and therefore ensuring simultaneously the repeatability and objectivity of assessment of the metallurgical quality of these alloys.

8

Stront jako modyfikator stopów AlSi i AlSiCu.

Łatkowski A., Bronicki M., Gryziecki J.

Rudy i Metale Nieżelazne

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1999

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R. 44, nr 3

101-107

PL

Opierając się na analizie zmian mikrostruktury określono optymalne ilości strontu zapewniające efekt modyfikacji w stopach AK7, AK9, AK11, AK52 i AK 104. Zbadano również trwałość modyfikatora poprzez kolejne przetopy odlewów. Przeprowadzono badania wpływu ilości modyfikatora na udarność stopów.

EN

The optimum strontium amount for good modification of AK7, AK9, AK11, AK52, AK104 alloys was determined on the base of the analysis of microstructural changes. The stability of the modifier was investigated on the way of succesive remelting of billets. The influence of amount of modifier on the impact strength of the alloys was established.