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1

Wady anodowych powłok tlenkowych na stopach aluminium. Cz. 2

Nowak M.

Stal, Metale & Nowe Technologie

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2014

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nr 11-12

72--74

PL

W części pierwszej artykułu przedstawiono wady anodowych powłok tlenkowych będące efektem nierównomiernej grubości powłoki oraz niewłaściwie przeprowadzonej operacji uszczelniania. W kolejnej części omówione zostaną wady powstałe w wyniku procesów odlewniczych, przeróbki plastycznej oraz mechanicznej obróbki powierzchniowej.

2

Study of pinholes genesis in iron castings

Elbel T., Hampl J., Senkypl M.

Archives of Foundry Engineering

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2011

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Vol. 11, iss. 1

21-26

EN

Purpose: The study concerns the formation of pinholes in castings formed by reaction between a green foundry mould and lamellar graphite cast iron. Great numbers of works have been aimed at clarifying the causes of pinholes formation in iron castings. In spite of this there exists no united opinion on the pinholes formation (genesis) and the authors of this contribution having studied this phenomenon in compacted graphite and spheroidal graphite iron castings were also aimed at lamellar graphite cast iron and they applied for it their knowledge gained in study of reoxidation processes during casting of ferrous alloys. Methodology: Experiments were done on castings of stepped bars moulded in green bentonite mixtures with s graduated moisture and with use of two types of carbonaceous matters. Metal was melted in a 100 kg induction furnace from the same charge. Inoculation was done in a ladle after pouring out from the furnace. Aluminium was dosed in the ladle in some cases and the inoculator kind was changed too. Results: Pinholes were present on castings as small flat pits; on horizontal surfaces sooner singly, on casting edges in clusters. The formation of pinholes wasn't caused by high moisture of moulds but the defect was sensitive to aluminium content in metal. In castings with high aluminium content > 0.01 % the pinholes were present in great numbers, and namely both under low, and also high moistures of moulding mixtures. In melts with low content of Al < 0.01 % the pinholes occurred less extensively only. Practical implications: Conclusions from literature about influence of Al on pinholes occurrence were confirmed in such a way. Study of the defect morphology has shown that the question is a oxidation reaction type of pinholes caused by oxidation of the residual melt between dendrites with formation of CO.

3

Computer system for casting defects classification based on Polish, French and Czech specifications

Adrian A., Durak J., Mrzygłód B., Kluska-Nawarecka S., Miłkowska K., Wilk-Kołodziejczyk D.

Archives of Foundry Engineering

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2009

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Vol. 9, iss. 3

5-8

EN

Many foundries existing in Poland make casts for local and external market. It is necessary to adopt a quality control to client's requirements. The main problem in the quality control of casting products is to detect and to classify properly defects. Polish defect classification is base nod the Polish Norm. In other countries (Czech Republic and France for example), other systems exist for classification, they are based on the different criteria and groups of defects. In other word the classification of casting defects is country-specific. Translation of defects names and their descriptions introduce additional level of difficulties. The authors propose multi-context system for finding equivalents of casting defects from one classification system to another, using original languages for each classification.