Nauki Techniczne

Archives of Foundry Engineering

Zawartość

Archives of Foundry Engineering | 2018 | vol.18 | No 3 |

Abstrakt

The paper presents selected granular ceramic materials available on the Polish market. Their characteristics have been determined in the aspect on application in the production of iron alloy-ceramic composite. The possibility of obtaining a composite layer by means of bulk grains in molds of plates were considered, which was the foundation for experimental molds to be used in service tests. On the basis of obtaining results was stated that the knowledge of the characteristics of bulk grains enables the calculation of their quantity necessary for the composite production. When using the bulk grains the thickness of the composite layer is restricted by the thermal relations (cooler) and the physical phenomena (buoyancy, metal static pressure). Increasing amount of grains above definite condition causes surface defects in the castings. Each casting, due to its weight, shape and place of composite layer production requires an individual approach, both at the stage of formation and that of calculation of the required quantity of ceramic grains.
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Silicon bronzes are characterised by good mechanical properties and by high corrosion and mechanical wear resistance. The process of sleeve casting by means of the centrifugal casting with the horizontal axis of the mould rotation was analysed. The assessment of the influence of modification and centrifugal casting parameters on the microstructure and mechanical properties of alloys was carried out in the hereby work. Zirconium was applied as a modifier. Speed of rotation of the mould was the variable parameter of the centrifugal casting. The investigation results were summarised on the basis of the microstructure analysis and mechanical properties determination: UTS, proof stress, A10 and BHN. The experiment aimed at finding the information in which way the modification together with changing the pouring parameters influence the mechanical properties of the CuSi3Zn3FeMn alloy.
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This work is dealing with the impact of molybdenum on the structure properties of commercial cast AlSi10Mg(Cu) alloy. The solidification path of AlSi10Mg(Cu) alloy with various content of molybdenum has been investigated using cooling curve techniques. The samples for testing have been poured into permanent steel mold. The content of molybdenum has been varied from 0 to 0.20 wt. %.The desired chemical composition was achieved by adding of master alloy AlMo10 into commercial AlSi10Mg(Cu) alloy. The micro hardness of as cast alloys with different content of molybdenum has been measured. The microstructure and EDX analysis from the casted samples has been carried out. The results show that molybdenum in commercial AlSi10Cu(Mg) alloy precipitate in the interdendritic region isolated in the form of Al(FeMnMoMg)Si rich intermetallic. The increased content of molybdenum increase slightly liquidus temperature, prolonging precipitation of the last eutectic and surprisingly decrease the micro hardness of commercial alloy for approximately 16 %.
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The paper deals with influence of multiple remelting on AlSi9Cu3 alloy with higher iron content on chosen mechanical properties. Multiple remelting may in various ways influence mechanical, foundry properties, gas saturation, shrinkage cavity, fluidity etc. of alloy. Higher presence of iron in Al-Si cast alloys is common problem mainly in secondary (recycled) aluminium alloys. In Al-Si alloy the iron is the most common impurity and with presence of other elements in alloy creates the intermetallic compounds, which decreases mechanical properties. Iron in the used alloy was increased to about 1.4 wt. %, so that the influence of increased iron content can be investigated. In the paper, the effect of multiple remelting is evaluated with respect to the resulting mechanical properties in cast state, after the heat treatment (T5) and after natural aging. From the obtained results it can be concluded that the multiple remelting leads to change of chemical composition and affect the mechanical properties.
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The paper describes the studies of ternary SnZn9Al1.5 lead-free alloy from the viewpoint of its mechanical behavior as well as microstructure examined by the light and scanning electron microscopy. The authors focused their attention specifically on the fatigue parameters determined by the original modified low-cycle fatigue method (MLCF), which in a quick and economically justified way allows determination of a number of mechanical parameters based on the measurement data coming from one test sample only. The effect of the addition of 1.5% Al to the binary eutectic SnZn9 alloy on its microstructure and the obtained level of mechanical parameters was analyzed. The phases and intermetallic compounds occurring in the alloy were identified based on the chemical analysis carried out in micro-areas by the SEM/EDS technique. It was shown that the addition of 1.5% Al to the binary eutectic SnZn9 alloy resulted in a more favorable microstructure and consequently had a positive effect on the mechanical parameters of the alloy. Based on the conducted research, it was recommended to use a combinatorial method based on the phase quanta theory to quickly evaluate the microstructure and the original MLCF method to determine a number of mechanical parameters.
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The paper describes influence of rare earth metals (REMs) on G20Mn5 cast steel microstructure and mechanical properties. The cerium mixture of the following composition was used to modify cast steel: 49.8% Ce, 21.8% La, 17.1% Nd, 5,5% Pr and 5.35% of REMs. Cast steel was melted in industrial conditions. Two melts of non-modified and modified cast steel were made. Test ingots were subject to heat treatment by hardening (920°C/water) and tempering (720°C/air). Heat treatment processes were also performed in industrial conditions. After cutting flashes off samples of cast steel were collected with purpose to analyze chemical composition, a tensile test and impact toughness tests were conducted and microstructure was subject to observations. Modification with use of mischmetal did not cause significant changes in cast steel tensile strength and yield strength, while higher values were detected for fractures in the Charpy impact test, as they were twice as high as values for the data included in the PN-EN 10213:2008 standard. Observations performed by means of light and scanning microscopy proved occurrence of significant differences in grain dimensions and morphology of non-metallic inclusions. Adding REMs resulted in grain fragmentation and transformed inclusion shapes to rounded ones. Chemical composition analyses indicated that round inclusions in modified cast steel were generally oxysulphides containing cerium and lanthanum. In the paper the author proved positive influence of modification on G20Mn5 cast steel mechanical properties.
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A research of wear resistance of an austenitic cast iron with higher resistance to abrasive-wear and maintained corrosion resistance characteristic for Ni-Resist cast iron is presented. For the examination, structure of raw castings was first formed by proper selection of chemical composition (to make machining possible). Next, a heat treatment was applied (annealing at 550 °C for 4 hours followed by air cooling) in order to increase abrasive-wear resistance. One of the factors deciding intensity of wear appeared to be the chilling degree of castings. However, with respect to unfavourable influence of chilling on machining properties, an important factor increasing abrasivewear resistance is transformation of austenite to acicular ferrite as a result of annealing non-chilled castings. Heat treatment of non-chilled austenitic cast iron (EquNi > 16%) resulted in much higher abrasive-wear resistance in comparison to the alloy having pearlitic matrix at ambient temperature (EquNi 5.4÷6.8%).
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The paper discusses the possibility of improving resistance of heat exchangers made of gray cast iron with flake graphite to hightemperature corrosion by providing them with metallic coatings. A metallic coating containing 76.9% Ni, 19.8% Cr, 1.7% Si, 0.9% Fe, and 0.9% Mn was applied by means of the plasma spraying method and subjected to cyclically variable thermal loads in the atmosphere of solid fuels combustion products (oxygen, sulfur, chlorine, and sodium). In a 30-day thermal load test held at temperature 500°C it has been found that thickness of the metallic coating decreased from the initial (240 ± 6) μm to (231 ± 6) μm. The depth to which sulfur, chlorine, and sodium penetrated the coating was about 30 μm. Increased oxygen content occurred along the whole coating depth. In the coating area adjacent to the substrate surface, the content was twice as high compared to this observed in the initial coating material. Although presence of oxygen was found within the whole depth of the coating, i.e. (231 ± 6) μm, no signs of susceptibility of the sprayed metallic layer to separation from substrate of gray cast iron with flake graphite were found.
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The study reported in this paper was aimed at establishing the effect of values of parameters characterizing the process of superficial remelting of a nodular iron casting on the quantity of introduced heat, geometry of remeltings as well as parameter λ and hardness of cementite eutectic. The remelting process was carried out using GTAW method, at electric arc length of 3 mm in argon atmosphere, welding current intensities I = 50, 130, 210, and 300 A, and electric arc scanning speeds vs = 200, 400, and 800 mm/min. The measurements included estimation of the quantity of heat introduced to the casting in the electric arc-induced remelting process with the use of flow calorimeter. Widths and depths of remetlings were assessed with the use of metallographic method. As a result of fast solidification, cementite eutectic was obtained in remelted material in which, in the course of cooling down to ambient temperature, austenite was subject to partial transformation into martensite. To characterize the cementite eutectic, value of the structural parameter λ was assessed. Values of the parameter were similar for areas of occurrence of both fibrous and laminated eutectic. Remeltings were examined at half of their depths. Micro-hardness measurements were taken in the same areas. The established quantitative relationships may prove to be useful in practice for the purpose of predicting values of parameter λ and hardness of remeltings in studies aimed at improving resistance of cast-iron castings to abrasive wear.
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Based on the example of the development process of the cast suspension of a special-purpose vehicle the application of the integrated engineering design methodology (ICME – Integrated Computational Materials Engineering) and the development of construction has been presented. Identification of the operating and critical loads, which are guidelines for carrying out the structure strength shaping process, material and technological conversion, are due to the needs and requirements of the suspension system and the purpose and objectives of the special mobile platform. The developed cast suspension element construction includes the use of high-strength AlZnMgCu aluminum alloy. The properties of the used alloy and designed shape allows for the transfer of assumed operating loads in normal exploitation conditions and in the dynamic, critical loads to the susceptibility to damage in the assumed casting areas. For the proposed design, conducted numerical analyzes includes the impact of the shock wave pulse on the occurrence of the destructive stress fields. Based on their distribution, the areas of possible decomposition of the structure of the design element were estimated. The results allowed to devise an element with predicted destructions that allow to absorb a significant part of the impact energy of the shock wave front, which is also the buffer zone for the propagation of destruction for the critical kinematic nodes of the system.
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The paper presents the results of the computer simulations of solidification with consideration of the liquid phase movement. Simulations were conducted in a real, complex cast. There is a multi-stage resolution to the problem of convection in solidification simulations. The most important resolution concerns the development of the numerical model with the momentum and continuity equations, as well as conditions which are determined by the convection. Simulations were carried out with the use of our authorial software based on stabilized finite elements method (Petroy-Galerkin). In order to solve Navier-Stokes equation (with the convection element), Boussinesq’s approximation were used. Finite Elements Method (FEM) was responsible for the solidification. FEM is close to the heat conduction equation solution (with the internal heat source responsible for the heat released during phase transformation). Convection causes movement in the liquid phase in the solidifying cast and can significantly influence the process of heat transfer from the cast. It may change the distribution of the defects. Results of this article make it possible to assess the conditions in which the influence of the convection on solidification is significant.
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Aluminium alloys are one of the preferred materials especially for land and air transportation because of their high strength and lowdensity properties. Although production using casting method is economical yet it has some disadvantages. Shrinkage which is occurred due to the density difference between the solid and liquid metal is prevented by feeders which need to be calculated. Liquid metal should be transferred to the mould without any turbulence. As a result, sprues are needed to be designed precisely. On the other hand, aluminium alloys can also be shaped by forging at semi-solid temperatures. There are some advantages compared to the traditional forging methods of improving die life due to the lower tonnage values. In this study, semi-solid produced 7075 aluminium alloy die filling capabilities were investigated. To achieve semisolid structure strain induced melt activated method (SIMA) was used. The desired structure was achieved at 635 °C and 30 minutes of duration of heat treatment. After determining the optimum parameters, metallographic analysis, density calculations, porosity distribution and tensile tests were carried out. It was found that the reproducibility of SIMA produced 7075 alloy was quite low. A proper tensile test result was achieved only 7 of the total 15 tests and the mean value was 386 MPa. The main reason for this scattered in mechanical properties could be the chemical composition of the alloy and the rapid solidification of the liquid eutectic phases. It is important to define the best fitting process parameters and controlling them precisely will be the most important factors for future studies.
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The author has developed and patented several types of gas cupola furnaces, which, due to replacing coke with gas, do not emit carbon monoxide, sulfur dioxide and coke dust. The author has defined the optimal modes of gas-and-air mixture combustion, i.e. the optimal coefficient of air discharge and gas mixture escape speed in melting cast iron. It has been experimentally proved that from the point of view of obtaining the maximum temperature, the optimal was the process with some lack of air, i.e. with α = 0.98. The results of metallurgical studies used in the article allowed to develop an optimal structure of the gas cupola furnace with a heterogeneous refractory filling, and to establish the optimal composition of the filling. For the first time the optimal composition of the filling is given: 40% of chamotte, 30% of high-alumina refractory, 30% of electrode scrap. It has been noted that when gas cupola furnaces were used, the main environmental advantage was the reduction of dust emission into the atmosphere, CO and SO2 content.
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The article describes the impact of germanium on the course of surface phenomena in casting alloys of silver used in gold smithing. The aim of this works is to describe the assessment of resulting alloys, comparing the area of raw castings and the impact of the addition content of the alloy on the hardness of the samples. The evaluation also was subject to corrosion resistance of giving a comparison of their use in relations to traditional silver alloys.
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The copper droplets contained in the post-processing liquid slag are subjected to the treatment by the complex reagent. The complex reagent has been recently elaborated and patented in frame of the Grant No. PBS3/A5/45/2015. In particular, the complex reagent is dedicated to the post-processing slags coming from the Smelter and Refinery Plant, Głogów, as a product of the direct-to-blister technology performed in the flash furnace. The recently patented complex reagent effectively assists not only in agglomeration, and coagulation but also in the deposition of the copper droplets at the bottom of crucible / furnace as well. The treatment of the postprocessing slags by the complex reagent was performed in the BOLMET S.A. Company as in the industrial conditions which were similar to those usually applied in the KGHM – Polish Copper (Smelter and Refinery Plant, Głogów). The competition between buoyancy force and gravity is studied from the viewpoint of the required deposition of coagulated copper droplets. The applied complex reagent improves sufficiently the surface free energy of the copper droplets. In the result, the mechanical equilibrium between coagulated copper droplets and surrounding liquid slag is properly modified. Finally, sufficiently large copper droplets are subjected to a settlement on the crucible / furnace bottom according to the requirements.
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Determination of the ferrite content in austenitic steels, which solidified under defined conditions. Ferrite content in austenitic matrix was determined from samples with wall thickness of 60 mm. Measured ferrite contents served to propose the regression equations for the calculation of the ferrite content in steels with Cr content of 18 up to 22 % and Ni of 9 up to 11 %. An additional regression equation was proposed for steels with a higher Ni content. The proposed regression equations have been checked up on the operating melts. In conclusion, the ferrite content in the axis of the casting of wall thickness of 500 mm has been calculated and it was compared to the ferrite determined in the usual way from the cast-on test.
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The article discusses the process of copper production in a slurry furnace and in a converter, with the indication of corrosion effects of the extractor. The furnace shaft and settling furnace of the flash furnace were analyzed. The basic factors determining the choice of singlestage technology of copper smelting in relation to the exploitation of refractory materials were indicated. The effects of dissolving the furnace lining material through slag have been presented. Structural analysis results using a scanning microscope are also included. The kinetics of destruction of ceramic materials under the influence of copper slag were evaluated. It has been shown that detailed analyzes are necessary in order to extend the time of furnace extensibility of furnaces in copper processes. The surface layer of the crucible softens due to saturation with slag reagents and is then washed out and moves in the solid form to the slag. The research in the article indicate not only the possibility of dissolution of the ceramic material in the molten slag, but also possibility of erosive activity of the slag on that material.
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An intentional change in material properties is an important condition for castings production. It is one way how to meet the casting requirements of how to adapt the material properties to the operating conditions. Centrifugally cast rolls are multi-layer rollers, castings. The working layer of the barrel is called the "shell" and the body of the roll and the necks rolls are called "core". The article deals with the influence of the properties of the core iron. Earlier laboratory experiments were primary analysed for metallographic analysis and mechanical properties. These data were compared back to the experiments. The results of these laboratory working were later applied in the operating conditions of the roll foundry Vítkovitcké slévárny, spol. s r.o. The spun cast roll produced with the applied metallurgical processing change was supplied to the hot strip mill. There were monitored the positive effect of the change of the metallurgical process of the production of the core iron on the useful properties of the centrifugally cast roll. The experiment was done in order to increase the mechanical properties of ductile pearlite ductile iron. The copper in these core iron material increases the hardness and strength primarily.
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Nowadays, there are growing demands on the accuracy of production. Most of this is reflected in precise manufacturing, such as the investment casting process. Foundries are looking for causes of defects in some cases for a very long time, and it may happen that the source of defects is completely different from what was originally assumed. During the casting process there exist potential causes of defects as oxygen inclusions. This paper represents a summary of the beginnings of a wider research that will address the problems of gating systems in investment casting technology. In general, the influence of the melt flow is underestimated and the aim of the whole scientific research is to demonstrate the significant influence of laminar or turbulent flow on the resulting casting quality. Specifically, the paper deals with the analysis of the most frequent types of defects found in castings made of expensive types of materials casted in an open atmosphere and demonstration of connection with the design of gating systems in the future.
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The results of investigations of sand shooting into the core box are presented in the hereby paper. The investigations concern the formation of the diphase sand-air flux, its motion, flowing and compaction in the cavity during the core forming. Conditions deciding on the course of individual phases of the process are discussed with taking into consideration the influence of such factors as: the shot pressure, shooting hole diameter, number and distribution of deaerating vents in experimental core boxes (of a single cavity and of multi cavities) on the core sand compaction state. Investigations were performed by means of the modernised experimental shooting machine SR-3D, of the shooting chamber volume of 3.3 dm3, connected with the system of pneumatic supply ensuring the stable pressure supply of values: 0.4 MPa, 0.5 MPa and 0.6 MPa. Two diameters of the shooting hole, equal 10 mm and 20 mm, were applied for filling three experimental core boxes differing in dimensions of cavities and in number and distribution of deaerating vents. The filling process of core boxes was recorded by means of the digital camera PHANTOM V210 with the filming rate of 3000 pictures in second. Simultaneously, during the shot, other values allowing to determine the intensity of the core sand outflow from the shooting chamber to the core box, were tested. The presented in this publication results constitute the important element of the experimental verification of the blowing process simulation calculations which will be performed.
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AZ91 alloy was cast in a steel mould pre-exposed to three different temperatures: -196 ºC, 20 ºC and 650 ºC. The aim of the study was to determine the difference in the microstructure and mechanical properties between the castings formed in a cold mould and those solidifying under near-equilibrium conditions in a mould pre-heated to 650 ºC. Solidification at a low temperature led to dispersion of the structure elements as well as supersaturation of the solid solution of aluminium in magnesium. The heat treatment results indicate that the alloy solidified in the mould pre-exposed to 20 ºC can be successfully aged (heat treated to the T5 temper). It was found that the effect of the ageing process (T5 temper) was greater than the effect of the microstructure fragmentation, which was due to rapid solidification. The ageing results were assessed by comparing the microstructure and mechanical properties of AZ91 brought to the T5 condition with those obtained for the material in the T6 condition.
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This work presents the project of the application of Case-based reasoning (CBR) methodology to an advisory system. This system should give an assistance by selection of proper alloying additives in order to obtain a material with predetermined mechanical properties. The considered material is silumin EN AC-46000 (hypoeutectic Al-Si alloy) that is modified by the addition of Cr, Mo, V and W elements in the range from 0% to 0.5% in the modified alloy. The projected system should indicate to the user the content of particular additives so that the obtained material is in the chosen range of parameters: tensile strength Rm, yield strength Rp0.2, elongation A and hardness HB. The CBR methodology solves new problems basing on the solutions of similar problems resolved in the past. The advantage of the CBR application is that the advisory system increases knowledge base as the subsequent use of the system. The presented design of the advisory system also considers issues related to the ergonomics of its operation.
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The necessity of obtaining high quality castings forces both researchers and producers to undertake research in the field of moulding sands. The key is to obtain moulding and core sands which will ensure relevant technological parameters along with high environmental standards. The most important group in this research constitutes of moulding sands with hydrated sodium silicate. The aim of the article is to propose optimized parameters of hardening process of moulding sands with hydrated sodium silicate prepared in warm-box technology. This work focuses on mechanical and thermal deformation of moulding sands with hydrated sodium silicate and inorganic additives prepared in warm-box technology. Tested moulding sands were hardened in the temperature of 140oC for different time periods. Bending strength, thermal deformation and thermal degradation was tested. Chosen parameters were tested immediately after hardening and after 1h of cooling. Conducted research proved that it is possible to eliminate inorganic additives from moulding sands compositions. Moulding sands without additives have good enough strength properties and their economic and ecological character is improved.
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The organo-inorganic commercial binder Albertine F/1 (Hüttenes-Albertus) constituting the starch-aluminosilicate mixture was directed to structural studies. The paper presents a detailed structural analysis of the binder before and after exposure to physical curing agents (microwaves, high temperature) based on the results of infrared spectroscopy studies (FTIR). An analysis of structural changes taking place in the binder system with the quartz matrix was also carried out. Based on the course of the obtained IR spectra, it was found that during the exposure on physical agents there are structural changes within the hydroxyl groups in the polymeric starch chains and silanol groups derived from aluminosilicate as well as in the quartz matrix (SiO2). The curing of the molding sand takes place due to the evaporation of the solvent water and the formation of intramolecular and intermolecular cross-linking hydrogen bonds. Type and amount of hydrogen bonds presence in cured molding sand have an impact on selected properties of molding sand. Results indicates that for molding sand with Albertine F/1 during conventional heating a more extensive network of hydrogen bonds is created.
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Metallic bearing alloys have different types, most of which are tin (Babbitt) or bronze based. Bronze bearings are used at heavy duty conditions. The goal of this research is an investigation on the effect of cooling rate and pouring temperature (two important factors in casting production) on the Brinell hardness and pin-on-disc wear resistance (two important properties in bearing applications) of bronze SAE660. The melt had prepared by induction furnace. Then, it had poured in sand mold in four different casting conditions, including pouring temperatures of 950 oC and 1200 oC, and cooling with water and air. Finally, the microstructure, hardness and wear resistance of the SAE660 had investigated. The results indicated that if the maximum hardness, along with the minimum weight loss due to wear (or maximum wear resistance) is required; the contents of intermetallic compounds, lead phase and the solid solution phase should be more. In this way, the samples which are cooled in air and poured at 950 oC have the high hardness and the lowest weight loss.
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It was found that the addition of carbon fibers (CFs) does not affect the crosslinking process in the microwave radiation (800 W, 2.45

GHz) of the BioCo2 binder, which is a water solution of poly(acrylic acid) and dextrin (PAA/D). It has influence on BioCo2 thermal

properties. The CFs addition improves the thermostability of a binder and leads to the reduction of gas products quantity generated in the

temperature range of 300-1100°C (TG-DTG, Py-GC/MS). Moreover, it causes the emission of harmful decomposition products such as

benzene, toluene, xylene and styrene to be registered in a higher temperatures (above 700°C). BioCo2 binder without CFs addition is

characterized by the emission of these substances in the lower temperature range. This indicates the positive effect of carbon fibers

presence on the amount of released harmful products.

The selected technological tests (permeability, friability, bending strength, tensile strength) have shown that the moulding sand with the

0.3 parts by weight carbon fibers addition displays the worst properties. The addition of 0.1 parts by weight of CFs is sufficient to obtain a

beneficial effect on the analyzed moulding sands properties. The reduction of harmful substances at the higher temperatures can also be

observed.

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The paper concerns experimental work studying chemical composition, structures and selected mechanical properties of castings produced by rheocasting method SEED. After previous experiments, which showed inclusions in the primary phase α(Al) when observing structures, hypothesis of external nuclei was taken. The main goal of the work was to determine the influence of inoculation by various additions of titanium/boron based inoculant on the structure and properties of AlSi7Mg0,3 alloy. The master alloy AlTi5B1 was added in amounts of 0,05, 0,1, 0,15, 0,2 wt %. Metallographic observation by light and SEM microscopy was used for analysing the structures. Measurements of grain size were realised and evaluated. Brinell hardness measurements were performed. Chemical composition was measured by GDS analysis. Undertaken experiments did not prove the effect of inoculation of combined AlTi5B1 master alloy on castings made of AlSi7Mg0,3 alloy made by rheocasting SEED at given amounts and conditions.

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Foundry technologists use their own style of gating system designing. Most of their patterns are caused by experience. The designs differ from plant to plant and give better or worse results. This shows that the theory of gating systems is not brought into general use sufficiently and therefore not applied in practise very often. Hence, this paper describes the theory and practical development of one part of gating systems - sprue base for automated horizontal moulding lines used for iron castings. Different geometries of sprue bases with gating system and casting were drawn in Solid Edge ST9. The metal flow through the gating systems was then simulated with use of MAGMA Express 5.3.1.0, and the results were achieved. The quality of flow was considered in a few categories: splashes, air entrapment, vortex generation and air contact. The economical aspect (weight of runner) was also taken under consideration. After quantitative evaluation, the best shape was chosen and optimised in other simulations with special attention on its impact on filling velocity and mould erosion. This design (a sprue base with notch placed in drag and cope) is recommended to be used in mass production iron foundries to reduce oxide creation in liquid metal and especially to still metal stream to improve filtration.

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Constantly developing production process and high requirements concerning the quality of glass determine the need for continuous improvement of tools and equipment needed for its production. Such tools like forms, most often made of cast-iron, are characterized by thick wall thickness compared to their overall dimensions and work in difficult conditions such as heating of the surface layer, increase of thermal stresses resulting from the temperature gradient on the wall thickness, occurrence of thermal shock effect, resulting from cyclically changing temperatures during filling and emptying of the mould. There is no best and universal method for assessing how samples subjected to cyclic temperature changes behave. Research on thermal fatigue is a difficult issue, mainly due to the instability of this parameter, which depends on many factors, such as the temperature gradient in which the element works, the type of treatment and the chemical composition of the material. Important parameters for these materials are at high temperature resistance to thermal shock and thermal fatigue what will be presented in this paper.

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Cast axes are one of the most numerous categories of bronze products from earlier phases of the Bronze Age found in Poland. They had multiple applications since they were not only used objects such as tools or weapons but also played the prestigious and cult roles.

Investigations of the selected axes from the bronze products treasure of the Bronze Age, found in the territory of Poland, are presented

in the hereby paper. The holder of these findings is the State Archaeological Museum in Warsaw. Metallurgical investigations of axes with bushing were performed in respect of the casting technology and quality of obtained castings. Macroscopic observations allowed to document the remains of the gating system and to assess the range and kind of casting defects. Light microscopy revealed the microstructure character of these relicts. The chemical composition was determined by means of the X-ray fluorescence method with energy dispersion (ED-XRF) and by the scanning electron microscopy with X-ray energy dispersion analysis in micro-areas (SEM-EDS). The shape and dimensions of cores, reproducing inner parts of axes were identified on the basis of the X-ray tomography images. Studies reconstructed production technology of the mould with gating system, determined chemical composition of the applied alloys and casting structures as well as revealed the casting defects being the result of construction and usage of moulds and cores.

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Redakcja

CHIEF EDITORS
Editor
J. Szajnar
Deputy Editor
J. Jezierski

SUBJECT EDITORS
Theoretical Aspects of Casting Processes
K. Eigenfeld – Freiberg, Germany
E. Guzik – Kraków, Poland
T. G. Mathia - Lyon, France
W. Wołczyński – Kraków, Poland
Innovative Foundry Technologies and Materials
T. Elbel – Ostrava, Czech Republic
Z. Ignaszak – Poznań, Poland
O. P. Pandey – Punjab, India
A. Pereira - Vigo, Spain
Foundry Processes Computer Aiding
B. Mochnacki – Częstochowa, Poland
J. Roučka – Brno, Czech Republic
J.S. Suchy – Kraków, Poland
Mechanization, Automation and Robotics in Foundry
J. Bast – Freiberg, Germany
R. Wrona – Kraków, Poland
Transport Systems in Foundry
J. Dańko – Kraków, Poland
Z. Li – Shijiazhuang, China
Castings Quality Management
D. Bolibruchova– Żilina, Slovak Republic
J. D. B. de Mello - Santa Monica, Brazil
M. Perzyk – Warszawa, Poland
Environment Protection
M. Holtzer – Kraków, Poland
H. Polzin – Freiberg, Germany
J. Sobczak – Kraków, Poland
I. Volchok – Zaporizhzhya, Ukraine

EDITORIAL ADVISORY BOARD
J. Braszczyński – Częstochowa, Poland
B. K. Dhindaw – Rupnagar, India
L. A. Dobrzański – Gliwice, Poland
W. A. Hufenbach – Dresden, Germany
P. Jelínek – Ostrava, Czech Republic
L. Jeziorski – Częstochowa, Poland
J. Lacaze – Toulouse, France
V. L. Naydek – Kiev, Ukraine
A. Passerone – Genova, Italy
I. Riposan – Bucharest, Romania
F. Romankiewicz – Zielona Góra, Poland
A. Sládek – Żilina, Slovak Republic

INTERNATIONAL SCIENTIFIC REVIEW COMMITTEE
S. A. Argyropoulos – Toronto, Canada
M. Azadi – Tehran, Iran
Y. Babaskin – Kiev, Ukraine
K. Bako – Miskolc, Hungary
E. Bayraktar – Paris, France
L. Bechný – Zilina, Slovak Republic
V. Bednarova - Ostrava, Czech Republic
F. Bińczyk – Katowice, Poland
A. Bokota – Częstochowa, Poland
G.P. Borisov – Kiev, Ukraine
A. Bydałek – Kraków, Poland
C. H. Cáceres – Brisbane, Australia
J. Čech – Brno, Czech Republic
L. Q. Chen – Shenyang, China
A. Chojecki – Kraków, Poland
M. Cholewa – Gliwice, Poland
I. A. Dibrov – Moscow, Russia
D. Dispinar – Istanbul, Turkey
S. M. Dobosz – Kraków, Poland
V. I. Dubodelov – Kiev, Ukraine
A. Fedoryszyn – Krakow, Poland
J. Głownia – Kraków, Poland
K. Granat – Wrocław, Poland
J. Hampl – Ostrava, Czech Republic
J. Helber – Düsseldorf, Germany
M. Hetmańczyk – Katowice, Poland
M. Horáček – Brno, Czech Republic
M. Kaczorowski – Warszawa, Poland
W. Kapturkiewicz – Kraków, Poland
R. Kawalla – Freiberg, Germany
Z. Konopka – Czestochowa, Poland
D. Kopyciński – Kraków, Poland
W. K. Krajewski – Kraków, Poland
Z. Libo – Beijing, China
P. Lichy – Ostrava, Czech Republic
Y. P. Lim – Setapak, Malaysia
T. Lipiński – Olsztyn, Poland
E. Majchrzak – Gliwice, Poland
A. Mityayev - Zaporizhzhya, Ukraine
M. Murgaš – Trnava, Slovak Republic
I. Nová – Liberec, Czech Republic
W. Orłowicz – Rzeszów, Poland
T. Pacyniak – Łódź, Poland
B. Piekarski – Szczecin, Poland
A. Rimmer – West Bromwich, United Kingdom
S. Samavedam – Hyderabad, India
P. Schumacher – Leoben, Austria
N. Sczygiol – Częstochowa, Poland
P. Skočovský – Żilina, Slovak Republic
M.S. Soiński – Częstochowa, Poland
J. Sokolowski – Ottawa, Kanada
K. V. Sudhakar – Butte, USA
B. G. Thomas - Champaign, USA
M. Trbižan – Ljubljana, Slovenia
J. Vuorinen – Tampere, Finland
E. Ziółkowski – Kraków, Poland
J. Zych – Kraków, Poland

ASSOCIATE EDITORS
D. Bartocha – Gliwice, Poland, - editorial secretary
J. Suchoń – Gliwice, Poland - editorial secretary
J. Szymszal – Katowice, Poland, Statistic Editor
A. Dulska – Gliwice, Poland
M. Kondracki – Gliwice, Poland
C. Borek –Chicago, USA, Language Editor

 

Kontakt

ul. Towarowa 7,
44-100 Gliwice, Poland
e-mail: kikm@polsl.pl

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