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1

Innovative Laboratory Procedure to Estimate Thermophysical Parameters of Iso-exo Sleeves

Ignaszak Z., Prunier J. B.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 1

67--72

EN

The paper is focused on properties testing of materials used in form of iso-exo sleeves for risers in ferrous alloys foundry. They are grainy-fibrous materials, containing components which initiate and upkeep exothermic reaction. Thermo-physical parameters characterizing such sleeves are necessary also to fill in reliable databases for computer simulation of processes in the casting-mould layout. Studies with use of a liquid alloy, especially regarding different sleeves bring valuable results, but are also relatively expensive and require longer test preparation time. A simplified method of study in laboratory conditions was proposed, in a furnace heated to a temperature above ignition temperature of sleeve material (initiation of exothermic reaction). This method allows to determine the basic parameters of each new sleeve supplied to foundries and assures relatively quick evaluation of sleeve quality, by comparison with previous sleeve supplies or with sleeves brought by new providers.

2

Effective Laboratory Method of Chromite Content Estimation in Reclaimed Sands

Ignaszak Z., Prunier J. B.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 3

162--166

EN

The paper presents an original method of measuring the actual chromite content in the circulating moulding sand of foundry. This type of material is applied for production of moulds. This is the case of foundry which most frequently perform heavy casting in which for the construction of chemical hardening mould is used, both the quartz sand and chromite sand. After the dry reclamation of used moulding sand, both types of sands are mixed in various ratios resulting that in reclaimed sand silos, the layers of varying content of chromite in mixture are observed. For chromite recuperation from the circulating moulding sand there are applied the appropriate installations equipped with separate elements generating locally strong magnetic field. The knowledge of the current ratio of chromite and quartz sand allows to optimize the settings of installation and control of the separation efficiency. The arduous and time-consuming method of determining the content of chromite using bromoform liquid requires operational powers and precautions during using this toxic liquid. It was developed and tested the new, uncomplicated gravimetric laboratory method using powerful permanent magnets (neodymium). The method is used in the production conditions of casting for current inspection of chromite quantity in used sand in reclamation plant.

3

Melting of Grey Cast Iron Based on Steel Scrap Using Silicon Carbide

Stojczew A., Janerka K., Jezierski J., Szajnar J., Pawlyta M.

Archives of Foundry Engineering

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2014

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Vol. 14, iss. 3

77--82

EN

The paper presents the issue of synthetic cast iron production in the electric induction furnace exclusively on the steel scrap base. Silicon carbide and synthetic graphite were used as carburizers. The carburizers were introduced with solid charge or added on the liquid metal surface. The chemical analysis of the produced cast iron, the carburization efficiency and microstructure features were presented in the paper. It was stated that ferrosilicon can be replaced by silicon carbide during the synthetic cast iron melting process. However, due to its chemical composition (30% C and 70% Si) which causes significant silicon content in iron increase, the carbon deficit can be partly compensated by the carburizer introduction. Moreover it was shown that the best carbon and silicon assimilation rate is obtained where the silicon carbide is being introduced together with solid charge. When it is thrown onto liquid alloy surface the efficiency of the process is almost two times less and the melting process lasts dozen minutes long. The microstructure of the cast iron produced with the silicon carbide shows more bulky graphite flakes than inside the microstructure of cast iron produced on the pig iron base.

4

Badania i rozwój nowoczesnej technologii tworzyw odlewniczych odpornych na zmęczenie cieplne - wybrane zagadnienia projektu realizowanego w Instytucie Odlewnictwa

Pytel A.

Przegląd Odlewnictwa

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2012

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Vol. 62, nr 5-6

214-216

PL

Przedstawiono wybrane zagadnienia realizowanego projektu nr POIG 01.03.01-061 pt. "Badania i rozwój nowoczesnej technologii tworzyw odlewniczych odpornych na zmęczenie cieplne". Podano ogólne założenia projektu i tematykę realizowanych zadań. Szczególną uwagę zwrócono na wykonane urządzenie do badania zmęczenia cieplnego stopów żelaza. Urządzenie wykonano w Instytucie Tele-i Radiotechnicznym w Warszawie na podstawie projektu i dokumentacji opracowanej w Instytucie Odlewnictwa w Krakowie.

EN

The selected problems of the Project No.POIG 0.1 03. 01-061, entitled: 'Research and Development of the Modern Technology of Heat Fatigue Resistant Foundry Materials', are presented in the paper. General assumptions of the Project and topics of the realized tasks are given. A special attention was directed towards the new device for testing a heat fatigue of ferrous alloys. This device was built in the Tele- Radiotechnical Institute in Warsaw on the basis of the design and documentation worked out in the Foundry Institute in Kraków.

5

Effect of temperature on the volume of gas emissions

Żółkiewicz Z., Karwiński A.

ECONTECHMOD : An International Quarterly Journal on Economics of Technology and Modelling Processes

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2012

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Vol. 1, No 2

75-77

EN

In the full mould process, the polystyrene pattern which fills the mould cavity is subjected to pouring of this mould with liquid metal to the effect of high temperature (1600 0C) and passes from the solid state into liquid and gas. During this process some solid and gaseous products of the thermal destruction of the pattern are created. The kinetics of this process depends on the temperature of evaporation and, though to a smaller extent, on the pattern density, which, combined with the mould parameters, parameters of a ceramic coating, i.e. its thickness, permeability, and resistance to the effect of high temperatures, parameters of a granular material filling the mould and parameters of a technological process, including the technique of pouring and design. The mould cavity is filled with a pattern made of foamed polystyrene which on pouring of mould with liquid metal undergoes total destruction.

6

Recykling materiałowy w pojazdach

Michalski R.

Recykling

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2009

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nr 3

42-44

PL

W Polsce zarejestrowanych jest ok. 16 mln pojazdów samochodowych, a wiek połowy z nich przekracza 10 lat. Z doświadczeń krajów UE wynika, że przy takim stanie i nasyceniu rynku niezbędne będzie wycofywanie minimum 500 tys. pojazdów rocznie. Przed operatorami recyklingu pojawi się więc wyzwanie zagospodarowania przeszło 500 tys. ton odpadów na rok.

7

Wpływ obróbki cieplnej na właściwości mechaniczne staliwa GS-20Mn5 przeznaczonego do pracy w obniżonej temperaturze

Gwiżdż A., Jaśkowiec K., Pirowski Z., Wodnicki J.

Prace Instytutu Odlewnictwa

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2009

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T. 49, z. 2

43-54

PL

Przedstawiona praca stanowi część badań przemysłowych (stosowanych) wykonanych w ramach projektu celowego ROW-II-403/2008 realizowanego w MAGNUS-NORD w Toruniu. Celem pracy było dobranie obróbki cieplnej zapewniającej uzyskanie założonych wartości udarności staliwa GS-20Mn5 w temperaturze -30°C oraz -55°C. W artykule nakreślono problem związany z przejściem stopów w stan kruchy przy obniżeniu temperatury eksploatacji. Ze względu na charakter produkcji odlewów w zakładach "Magnus-Nord" w Toruniu praca dotyczyła możliwości uzyskania, w warunkach tej odlewni, staliwa konstrukcyjnego niskostopowego z przeznaczeniem na wybrane odlewy pracujące w temperaturze poniżej -20°C. Przeprowadzono wytopy staliwa GS- 20Mn5, a następnie dobrano parametry obróbki cieplnej tego stopu umożliwiające osiągnięcie odpowiedniej udarności w temperaturze -30°C (20-50 J) i temperaturze -55°C (20-30 J).

EN

The study formed a part of industrial (applied) research executed under Target Project ROW-II-403/2008 at MAGNUS-NORD in Toruń. The aim of the study was to select the heat treatment parameters ensuring the required impact resistance values of GS-20Mn5 cast steel when operating at-30°C and -55°C. The study outlines the problem of alloy embrittlement when operating at low temperatures. Considering the production profile of "Magnus-Nord" Toruń, the study mainly regarded the possibilities of manufacturing under the conditions of this specific Foundry, the structural low-alloyed steel for castings operating at temperatures below -20°C. Consequently, the GS-20Mn5 steel was melted and, as a next step, parameters of the heat treatment of this alloy were selected to satisfy the requirements to obtain the required impact resistance at temperatures of -30°C (20-50J) and -55°C (20-30).

8

Ferrous alloys cast under high pressure gas atmosphere

Pirowski Z., Olszyński J., Gwiżdż A.

Archives of Foundry Engineering

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2007

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Vol. 7, iss. 1

107-112

EN

The main objective of this paper is describing the essence of the process of introducing nitrogen to the melt of ferrous alloys by application of overpressure above the metal bath. The problem was discussed in terms of both theory (the thermodynamic aspects of the process) and practice (the technical and technological aspects, safety of the furnace stand operation, and technique of conducting the melt). The novel technique of melting under high pressure of the gas atmosphere (up to 5 MPa) has not been used so far in the domestic industry, mainly because of the lack of proper equipment satisfyng the requirements of safe operation. Owing to cooperation undertaken with a partner from Bulgaria, a more detailed investigation of this technology has become possible and melting of selected ferrous alloys was conducted under the gas atmosphere at a pressure of about 3,5 MPa.

9

Morfologiczne aspekty procesu umacniania wielofazowych stopów żelaza pod wpływem naprężeń eksploatacyjnych

Pirowski Z.

Odlewnictwo - Nauka i Praktyka

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2005

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R. 7, nr 4

3-18

PL

Scharakteryzowano proces umocnienia stopów pod wpływem naprężeń zewnętrznych. Przedstawiono w sposób skrótowy ważniejsze grupy stopów żelaza szczególnie podatne na ten rodzaj umocnienia. Przeprowadzono próby oceny tego zjawiska na wybranych wysokojakościowych stopach żelaza. W tym celu wykonano wytopy stopowego żeliwa sferoidalnego i wysokostopowego staliwa. Wytopy prowadzono w tyglowym piecu indukcyjnym z atmosferą naturalną. Z odlanych stopów wykonano próbki do badań laboratoryjnych. Przeprowadzono badania wytrzymałościowe, metalograficzne i erozyjne, porównując uzyskane wyniki na próbkach poddanych wstępnym naprężeniom zewnętrznym (powyżej R_p0.2 ) z wynikami na próbkach nie poddanych tym naprężeniom. Na podstawie poczynionych obserwacji stwierdzono, że w wyniku przyłożenia zewnętrznych naprężeń rozciągających badane stopy zachowywały się odmiennie. W strukturze tylko niektórych z nich stwierdzono zmniejszenie się ilości austenitu. W istotny sposób nastąpiło to w przypadku staliwa dwufazowego o niewielkiej zawartości azotu (0,19%), nieznacznie - w staliwie dwufazowym o zwiększonej zawartości azotu (0,40%) i w żeliwie sferoidalnym hartowanym z przemianą izotermiczną (ADI). W przypadku pozostałych badanych stopów tego zjawiska nie zaobserwowano. Zastosowane rozciągające naprężenia zewnętrzne o wartości 80% naprężeń zrywających nie wpłynęły istotnie na umocnienie badanych stopów, natomiast naprężenia ściskające znacznie te stopy umocniły. Zaobserwowano wzrost twardości, nawet o około 40%, w przypadku staliwa duplex z dodatkiem 0,4% azotu i żeliwa ADI. Realizując pracę, poczyniono wstępne kroki w kierunku aplikacji uzyskanych wyników badawczych. Z wybranych stopów wykonano odlewy wkładek matryc do prasowania kształtek ceramicznych i przekazano je do wstępnych prób eksploatacyjnych.

EN

The process of alloys strain hardening under the influence of external stresses is characterised. The more important groups of ferrous alloys specially susceptible to this kind of hardening are shortly presented. To this end melts of alloyed spheroidal cast iron and highly alloyed cast steel were made. The melts were carried out in a crucible induction furnace with natural atmosphere. Specimens for laboratory tests were prepared of the melted alloys. Strength, metallographic and erosion tests were carried out and the results obtained on the specimens subjected to the initial external stresses (over R _p0.2) were compared with the results obtained on specimens which were not subjected to those stresses. On the basis of the observations made it was stated that as a result of the applied external tensile stresses the tested alloys behaved in a different way. In the structure of only some of them the reduction in austenite content was stated. This effect was notable in the diphase cast steel with a low content of nitrogen (0.19%) and insignificant in both diphase cast steel with increased content of nitrogen (0.40%) and in austempered ductile iron (ADI). In the case of the remaining tested alloys this phenomenon was not observed. The applied external tensile stresses of the value of 80% of the rupture stresses had no significant effect on the strain hardening of the investigated alloys, whereas the compressive stresses considerably hardened these alloys. The increase in hardness even by about 40% was observed in duplex cast steel with the additions of 0.4% of nitrogen and in ADI. In execution of this study the initial steps concerning the application of the obtained investigation results were made. From the selected alloys die inserts for pressing ceramic shaped elements were cast and they were used in preliminary performance trials.