Assessment of the Low Alloy Cast Steel Inoculation Effects with Chosen Additives

Structure, and thus the mechanical properties of steel are primarily a function of chemical composition and the solidification process which can be influenced by the application of the inoculation treatment. This effect depends on the modifier used. The article presents the results of studies designed to assess the effects of structural low alloy steel inoculation by selected modifying additives. The study was performed on nine casts modeled with different inoculants, assessment of the procedure impact was based on the macrostructure of made castings. The ratio of surface area equivalent to the axial zone of the crystals and columnar crystals zone was adopted as a measure of the inoculation effect

Two-Phase Cast Steel Production with Regenerative Method

W pracy przedstawiono wyniki próbnych wytopów staliwa GX2CrNiMoCuN25-6-3-3 przeprowadzonych w otwartym laboratoryjnym piecu indukcyjnym sposobem odzyskowym. Wytopy polegały na przetopieniu złomu staliwa duplex, a zabiegi ograniczono tylko do końcowego odtlenienia. W ramach każdego wytopu wykonane zostały odlewy próbne schodkowe. Przedstawiono wyniki badań składu chemicznego i określono jego zmiany w różnym stadium wytopu. Na podstawie badań mikrostruktury i symulacji krzepnięcia odlewów próbnych określono wpływ szybkości stygnięcia na strukturę badanego staliwa.In the article the results of trial melts of cast steel grade GX2CrNiMoCuN25-6-3-3 conducted in an open laboratory inductive furnace with regenerative method are presented. Melts consisted on remelting scrap of duplex cast steel, and metallurgical treatment is limited only to the final deoxidation. Within each melts step-test castings are made. The results of chemical composition analysis are presented and it changes in the various stages of melting have been determined. On the basis of microstructure analysis and simulation of casting solidification, the effect of cooling rate on the structure of the tested cast steel has been estimated

A R C H I V E S of F O U N D R Y E N G I N E E R I N G Computer simulation of carburizers particles heating in liquid metal

Abstract In this article are introduced the problems of computer simulation of carburizers particles heating (anthracite, graphite and petroleum coke), which are present in liquid metal. The diameter of particles, their quantity, relative velocity of particles and liquid metal and the thermophysical properties of materials (thermal conductivity, specific heat and thermal diffusivity) have been taken into account in calculations. The analysis has been carried out in the aspect of liquid metal carburization in metallurgical furnaces

Influence of Tin Bronze Melting and Pouring Parameters on Its Properties and Bells’ Tone

The most important feature of bells is their sound. Its clarity and beauty depend, first of all, on the bell’s geometry - particularly the shape of its profile, but also on the quality of alloy used to its cast. Hence, if the melting and pouring parameters could influence the alloy’s properties, what influence they would have on the frequencies of bell’s tone. In the article authors present their own approaches to find answers on that and more questions

Prototype Stand for Determining Quantities of Gasification Products of Polystyrene Model

Disposable foundry models constitute an increasingly important role in a unitary large-size foundry. These models have many benefits, but technologies using such materials require an understanding of degradation kinetics at the time of filling. The studies presented in the article determine the size of the polystyrene combustion products used for disposable foundry models. The results were obtained by carrying out the combustion process of the polystyrene model in a special combustion chamber, in different configurations. The pressures generated during thermal degradation vary depending on process parameters such as model density or the use of an additional adhesive binder. The results of laboratory tests may suggest what values of pressure are generated when filling in full-mold and lost foam technologies. The studies provide a prelude to further analysis of materials used for disposable foundry models and quantitative evaluation of their thermal degradation products for computer simulation

Structure of low-alloy constructional cast steel - a quantitative analysis of impurities

The mechanical properties of cast steel are primarily a function of chemical composition and solidification conditions i.e. primary structure, however, a significant role also plays its quality understood as purity metallurgical i.e. as small as possible content of harmful components of the structure. In work the results of porosity and non-metallic inclusions in steel cast structure quantity analysis are presented.A function which coefficient can be treated as parameters of unwontedstructurecomponent was statistically fittedto histograms of impurities distribution. The influence of O, N, P and S content on approximation function coefficients was analyzed

„The Secret” of Traditional Technology of Casting Bells

Artykuł poświęcono zagadnieniu technologiczności tradycyjnego sposobu odlewania dzwonów. Pomimo złamania podstawowych zasad poprawnego projektowania technologii odlewania, tradycyjna technologia wykonywania dzwonów sprawdza się od setek lat. Autorzy analizując wyniki badań brązu CuSn20-C oraz tradycyjnej masy formierskiej używanej do wykonywania form na dzwony, próbują wykazać na czym polega tajemnica fenomenu najstarszej z aktualnie stosowanych technologii odlewania.The article are devoted to the issue of manufacturability of the traditional way of casting bells. Despite breaking the fundamental principles of proper casting technology design, traditional technology of casting bells has works for hundreds of years. The authors have analyzing the investigations results of a bronze CuSn20-C and traditional molding sand is used to produce molds for bells and they have been trying to demonstrate what is the secret of the marvel of the oldest currently used casting technology

The Influence of Solidification Rate on High-tin Bronze Microstructure

The most important feature of bells is their sound. Their clarity and beauty depend, first of all, on the bell’s geometry - particularly the shape of its profile and the mechanical properties of alloy. Bells are the castings that work by emitting sound in as-cast state. Therefore all features that are created during melting, pouring, solidification and cooling processes will influence the bell's sound. The mechanical properties of bronze depend on the quality of alloy and microstructure which is created during solidification and depend on its kinetics. Hence, if the solidification parameters influence the alloy’s properties, how could they influence the frequencies of bell`s tone? Taking into account alterable thickness of bell's wall and differences in microstructure, the alloy's properties in bell could be important. In the article authors present the investigations conducted to determine the influence of cooling kinetics on microstructure of bronze with 20 weight % tin contents

The factors affecting the recarburization process indicators

W artykule przedstawiono czynniki wpływające na uzyskiwane wskaźniki nawęglania (szybkość i efektywność) w procesie wytapiania żeliwa. Analiza obejmuje rodzaj nawęglacza (antracyt, grafit naturalny i grafit syntetyczny , koks naftowy ) oraz wielkość cząstek. Kolejne czynniki rozpatrywane w pracy to metoda nawęglania (wprowadzanie nawęglacza do stałego wsadu i na powierzchnię kąpieli metalowej) oraz parametry ciekłego metalu (temperatura i skład chemiczny ). Analizę przeprowadzono w oparciu o wykonane eksperymenty , wyniki obliczeń symulacji komputerowych oraz dane literaturowe.The article presents the factors affecting the carburizing rates obtained (rate and efficiency) during the process of melting cast iron. The analysis includes the recarburizer type (anthracite, natural and synthetic graphite, petroleum coke) and particle size. Further factors considered in work are the methods of recarburization (recarburizer introduction to a solid charge and on the surface of the metal bath) and the parameters of the melt (temperature and chemical composition). The analysis was based on experiments performed, the calculation results of computer simulations and literature data