Wyniki wyszukiwania - Biblioteka Nauki

1

Zastosowanie koncepcji ważonego wykresu Ishikawy do analizy wad odlewów

100%

Łybacki W. , Zawadzka K.

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2009

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tom Vol. 59, nr 7-8

430-433

PL

Przedstawiono sposób analizy wad odlewów oparty na koncepcji ważonego diagramu Ishikawy. Znany diagram Ishikawy, po określeniu zbioru przyczyn głównych i zbioru podprzyczyn, uzupełnia się o wagi cząstkowe. Przypisanie poszczególnym przyczynom i podprzyczynom wag pozwala wyodrębnić na wykresie Ishikawy przyczyny najistotniejsze i wyeliminować mniej ważne. Na konkretnym przykładzie przedstawiono metodykę analizy wad odlewów ilustrując kolejne kroki odpowiednimi tabelami i rysunkami.

EN

The method of an analysis of casting defects based on the conception of the weighed Ishikawa- diagram has been presented. The well known Ishikawa-diagram, after determination of the set of main reasons and of the set of underreasons, is completed with the partial weights. Ascribing of weights to the particular reasons and underreasons allows isolating, on the Ishikawa-diagram the most essential reasons and eliminating the less essential ones. By help of a concrete example was presented the methodology of casting defects analysis; the successive steps are illustrated with apropriate tables and figures.

2

Study of pinholes genesis in iron castings

86%

Elbel T. , Hampl J. , Senkypl M.

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2011

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tom 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

Analysis of the failure causes in an element made of AlSi11Cu2(Fe) alloy

86%

Golański G. , Zyska A. , Werner K. , Stokłosa H.

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2011

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tom Vol. 11, iss. 2

29-34

EN

The paper presents results of research on a cross element damaged during the service, made of the casting alloy of aluminum - AlSi11Cu2(Fe) (AK132). Performed research was to explain the reasons for this damage and included microstructural observation as well as the investigation on mechanical properties. On the basis of the tests carried out it has been noticed that there is significant inhomogeneity of the structure characterized by the presence of both: normally modified eutectic areas (\alfa + Si) and needle-shaped primary silicon crystals. On the cross-section of the cast wall there were numerous casting defects of diverse size observed - shrinkage porosity. On the basis of the research it has been concluded that the damage of the examined element occurred as a result of fatigue cracking initiated from the surface near the marks left by the knock-outs, while the subsequent propagation of the crack ran along the primary precipitates of silicon crystals as well as through the crystals.

4

Napawanie technologią TIG jako sposób naprawy wad odlewniczych w żeliwie chromowym

86%

Szajnar J. , Wróbel P. , Wróbel T.

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2006

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tom R. 6, nr 22

490-496

PL

Naprawę odlewów żeliwnych przeprowadza się w związku z koniecznością eliminowania wad odlewniczych obniżających ich stopień przydatności do zastosowań konstrukcyjnych oraz w celu ograniczenia kosztów wynikających z konieczności zastąpienia odlewu wadliwego odlewem nowym wolnym od wad. W pracy przedstawiono wyniki badań mających na celu określenie przydatności napawania na zimno technologią TIG do naprawy wadliwych odlewów z żeliwa stopowego chromowego o zawartości 16% Cr.

EN

Repair of cast iron elements realize in order to cut out a casting defects. Casting defects decrease a usability of cast to constructional application and increase a manufacturing costs. The paper presents research results of use of TlG surfacing on cold to repair chromium cast iron with 16% Cr.

5

Knowledge representation of casting metal defects by means of ontology

72%

Kluska-Nawarecka S. , Smolarek-Grzyb A. , Wilk-Kołodziejczyk D. , Adrian A.

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2007

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tom Vol. 7, iss. 3

75-78

EN

The scattered nature of information requires implementation of appropriate tools and system solutions. The conception of decentralized diagnostic system of casting metal defects, in which the methods of concept classification in the form of ontology are used, has been presented in the article. Also, the general rules of ontology creation, model division into modules, the hierarchy of classes and their instances have been introduced. There has been provided an example of ontology construction for casting defects.

6

Hydrogen analysis and effect of filtration on final quality of castings from aluminium alloy AlSi7Mg0,3

72%

Brůna M. , Sládek A.

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2011

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tom Vol. 11, iss. 1s

5-10

EN

The usage of aluminium and its alloys have increased in many applications and industries over the decades. The automotive industry is the largest market for aluminium castings and cast products. Aluminium is widely used in other applications such as aerospace, marine engines and structures. Parts of small appliances, hand tools and other machinery also use thousands of different aluminium castings. The applications grow as industry seeks new ways to save weight and improve performance and recycling of metals has become an essential part of a sustainable industrial society. The process of recycling has therefore grown to be of great importance, also another aspect has become of critical importance: the achievement of quality and reliability of the products and so is very important to understand the mechanisms of the formation of defects in aluminium melts, and also to have a reliable and simple means of detection.

7

Zastosowanie metod sztucznej inteligencji do klasyfikacji wad w odlewach ze stopów Al-Si-Cu

72%

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

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2006

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tom R. 6, nr 22

598-605

PL

Praca dotyczy oceny jakości elementów np. korpusów silników samochodowych ze stopów aluminium wytworzonych metodą Cosworth, przy wykorzystaniu analizy obrazów zdjęć cyfrowych uzyskanych w wyniku rentgenograficznych badań defektoskopowych tychże elementów. Uzyskane wyniki decydują o tym, czy wytworzony produkt jest odpadem poprodukcyjnym czy też nie, co ma na celu zmniejszenie liczby wytwarzanych produktów niespełniających kryteriów kontroli technicznej. W pracy przedstawiono opracowaną, komputerowo wspomaganą metodę oceny jakości odlewów, na podstawie morfologii wad, przy zastosowaniu narzędzi sztucznej inteligencji.

EN

This paper presents the analysis of automotive alloy castings of engine heads and blocks. The technological process applied for these Al-Si alloy castings, EN AC-AISi7Cu3Mg type, was Cosworth. AIso, it includes the development of the methodology of image analysis of casting defects. They were achieved by the defectoscopic X-ray analysis of AI-Si-Cu alloy elements, EN AC-AISi7Cu3Mg type. Besides, it contains both the manner of classification of casting defects by means of artificial intelligence, including neural networks and the application of the developed methodology in the form of a system of computer programmes for quality controI.

8

An establish attempt of reasons of machining splinter formation in AC44200 alloy high pressure die castings

72%

Mutwil J.

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2008

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tom Vol. 8, iss. 3

159-166

EN

A problem of splinter formation during machining the AC44200 alloy high pressure die casting has been experimental investigated. In order to establish the reason of this occurrence a set of 200 high pressure die casting of the tensile strength samples have been prepared. The tensile tests were carried out using a Zwick Z050 universal testing machine. JM-SPC program has been used for statistical analysis of test results. A large variability of tensile strength results has been found. In order to find the reason of this variability the fracture surface investigations (macrographs for all of samples and SEM micrographs for chosen samples) have been carried out. It has been establish that in all cases a significant decrease of tensile strength was caused by presence of inclusions or porosity. In lot of cases the inclusions have a form of oxide film.

9

Surface quality of foundry pattern manufactured by FDM method - rapid prototyping

58%

Hanus A. , Špirutová N. , Beňo J.

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2011

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tom Vol. 11, iss. 1s

15-20

EN

The goal of this paper was to verify the possibilities of using 3D models produced by means of the FDM technology for actual foundry production. Experimental models were produced using Dimension sst 768 3D printer. Two types of castings (type I - simple plates, type II - jewellery) were cast in plaster moulds. The models were burnt out at 500 oC. The goal of the experiment was to verify the effect of modifications upon surface quality of the resulting casting. The ABS model was tested with unmodified surface, chemically treated surface, blasted surface and blasted and etched surface together. The results of the experiment have confirmed the assumed effect of both mechanical and chemical modifications of the model surface on casting surface quality.