Wyniki wyszukiwania - BazTech

1

Selection of materials and development of technology for the production of elements used in conditions of extreme tribological wear

Wilk-Kołodziejczyk D., Pirowski Z., Grudzień-Rakoczy M., Bitka A., Chrzan K.

Archives of Foundry Engineering

|

2021

|

Vol. 21, iss. 4

47--54

EN

Work was done as a part of the project " New generation haulage system of highly productive longwall systems" aiming to develop and implement a new longwall shearer system called KOMTRACK. The widely used EICOTRACK feed system developed forty years ago is not adapted to modern longwall shearers' power. Within the project, an innovative, flexible feed system with a modular structure was created with the possibility of continuous adjustment to the carbon wall's unevenness. Newly-developed three cast steels variants have been initially selected to fabricate this system's elements. The material's final selection was realized based on the tensile tests, Charpy impact tests, Brinell hardness surveys, and wear resistance measurements. Results analysis allowed to select cast steel marked as "2", which fulfilled all requirements and was used in further casting trials.

2

Studies of Binding Kinetics and Choice of Self-Hardening Moulding and Core Sands Used for Casting Massive Parts for Wind Power Industry under the Conditions of Krakodlew Foundry

Rączka M., Isendorf B.

Archives of Foundry Engineering

|

2017

|

Vol. 17, iss. 2

222--226

EN

In highly developed countries, a significant progress in the use of alternative and clean energy sources has recently been observed. The European Union has implemented a programme to build wind turbines. It is estimated that in the coming years, thanks to the support in tax and credit, the global energy will develop very intensively. Many components of the wind turbines are castings. The basic material used for these castings is ductile iron, which in this particular case must meet high requirements imposed by the operating conditions of wind turbines. Anticipating an increase in customer demand for this type of castings, Krakodlew SA has decided to modernize its foundry using the ability to obtain external financing. The ductile iron manufacturing technology is now being developed and adapted to the specific conditions of the foundry plant, including the melting process yielding cast material with the required chemical composition, the technology of moulding, and the conditions for possible secondary metallurgy, spheroidizing treatment and graphitizing inoculation. The fulfilment of the imposed conditions for the casting production demands the use of advanced casting technologies introduced to the manufacturing process. The development of technology to launch the production of ductile iron castings for the wind power industry was supported by The National Centre for Research and Development (NCBiR). This article presents part of research on the binding kinetics of furan resin sands and choice of their composition for moulds and cores to make heavy castings used as components of equipment for the wind power industry.

3

Method and Apparatus for Assessing the Properties of Slags

Biernat S., Bydałek A. W., Wołczyński W., Holtzer M.

Archives of Foundry Engineering

|

2017

|

Vol. 17, iss. 3

13--18

EN

A special Slag-Prop Cu database has been developed to archive data from laboratory and industrial tests related to post-reduction slags. In order to enrich the data areas, it was decided to design a system for measuring the temperature of the liquid slag and its viscosity. Objectives of research work are to gather information on the properties of post-slags such as the temperature of liquid slag and its viscosity. The discussed issues are especially important in the foundry practice. Designed research stand and using of database applications can greatly facilitate the work of metallurgists, foundrymen, technologists and scientists. The viscosity measurement was developed and presented earlier. The author's analytical methodology was supplemented by a thyristor measuring system (described in the article). The system temperature measurement can be performed simultaneously in 3 ways to reduce the measurement error. Measurement of the voltage mV - using the Seebeck effect can be measured throughout the entire range of thermocouple resistance, up to 1300 °C. Direct temperature measurement ⁰C - measurement only below 1000 ⁰C. Additional measurement - the measurement can also be read from the pyrometer set above the bath. The temperature and the reading frequency depend on the device itself. The principle of measurement is that in a molten metal / slag crucible, we put a N-type thermocouple. The thermocouples are hung by means of a tripod above the crucible and placed in a crucible. The thermocouple is connected to a compensating line dedicated to this type of thermocouple. The cable is in turn connected to a special multimeter that has the ability to connect to a computer and upload results. Temperature measurement can be performed simultaneously in 3 ways to reduce the measurement error. The Sn-Pb alloy has been subjected to testing for proper operation of the device. In this foot should be observed the supercooling of the liquid, which initiates the crystallization process and in which latent heat begins to exude raising the temperature until the coagulation temperature is reached.

4

Effect of Alloy Additions on the Structure and Mechanical Properties of the AlSi7Mg0.3 Alloy

Pisarek B. P., Rapiejko C., Szymczak T., Pacyniak T.

Archives of Foundry Engineering

|

2017

|

Vol. 17, iss. 1

137--142

EN

The study presents the results of the investigations of the effect of Cu, Ni, Cr, V, Mo and W alloy additions on the microstructure and mechanical properties of the AlSi7Mg0.3 alloy. The examinations were performed within a project the aim of which is to elaborate an experimental and industrial technology of producing elements of machines and devices complex in their construction, made of aluminium alloys by the method of precision investment casting. It was demonstrated that a proper combination of alloy additions causes the crystallization of complex intermetallic phases in the silumin, shortens the SDAS and improves the strength properties: Rm, Rp0.2,HB hardness. Elevating these properties reduces At, which, in consequence, lowers the quality index Q of the alloy of the obtained casts. Experimental casts were made in ceramic moulds preliminarily heated to 160 °C, into which the AlSi7Mg0.3 alloy with the additions was cast, followed by its cooling at ambient temperature. With the purpose of increasing the value of the quality index Q, it is recommended that the process of alloy cooling in the ceramic mould be intensified and/or a thermal treatment of the casts be performed (ageing) (T6).

5

ATD and DSC Analysis of IN-713C and ZhS6U-VI Superalloys

Binczyk F., Cwajna J., Gradoń P.

Archives of Foundry Engineering

|

2017

|

Vol. 17, iss. 1

13--16

EN

Paper presents the results of ATD and DSC analysis of two superalloys used in casting of aircraft engine parts. The main aim of the research was to obtain the solidification parameters, especially Tsol and Tliq, knowledge of which is important for proper selection of casting and heat treatment parameters. Assessment of the metallurgical quality (presence of impurities) of the feed ingots is also a very important step in production of castings. It was found that some of the feed ingots delivered by the superalloy producers are contaminated by oxides located in shrinkage defects. The ATD analysis allows for quite precise interpretation of first stages of solidification at which solid phases with low values of latent heat of solidification are formed from the liquid. Using DSC analysis it is possible to measure precisely the heat values accompanying the phase changes during cooling and heating which, with knowledge of phase composition, permits to calculate the enthalpy of formation of specific phases like γ or γ′.

6

Application of Modified Cores for Grain Refinement in Castings of Aircraft Turbine Blades

Binczyk F., Cwajna J., Gradoń P.

Archives of Foundry Engineering

|

2017

|

Vol. 17, iss. 3

19--22

EN

Paper presents the results of research on modified surface grain refinement method used in investment casting of hollow, thin-walled parts made of nickel based superalloys. In the current technology, the refining inoculant is applied to the surface of the wax pattern and then, it is transferred to the ceramic mould surface during dewaxing. Because of its chemical activity the inoculant may react with the liquid metal which can cause defects on the external surface of the cast part. The method proposed in the paper aims to reduce the risk of external surface defects by applying the grain refiner only to the ceramic core which shapes the internal surface of the hollow casting. In case of thin-walled parts the grain refinement effect is visible throughout the thickness of the walls. The method is meant to be used when internal surface finish is less important, like for example, aircraft engine turbine blades, where the hollowing of the cast is mainly used to lower the weight and aid in cooling during operation.

7

Influence of Modification and Casting Technology on Structure of IN-713C Superalloy Castings

Binczyk F., Cwajna J., Gradoń P., Mańka M.

Archives of Foundry Engineering

|

2016

|

Vol. 16, iss. 3

11--14

EN

The paper presents the results concerning impact of modification (volume and surface techniques), pouring temperature and mould temperature on stereological parameters of macrostructure in IN713C castings made using post-production scrap. The ability to adjust the grain size is one of the main issues in the manufacturing of different nickel superalloy castings used in aircraft engines. By increasing the grain size one can increase the mechanical properties, like diffusion creep resistance, in higher temperatures. The fine grained castings. on the other hand, have higher mechanical properties in lower temperatures and higher resistance to thermal fatigue. The test moulds used in this study, supplied by Pratt and Whitney Rzeszow, are ordinarily used to cast the samples for tensile stress testing. Volume modification was carried out using the patented filter containing cobalt aluminate. The macrostructure was described using the number of grains per mm2, mean grain surface area and shape index. Obtained results show strong relationship between the modification technique, pouring temperature and grain size. There was no significant impact of mould temperature on macrostructure.

8

Effect of the Annealing Temperature on the Microstructure and Properties of Ausferritic Nodular Cast Iron

Gumienny G., Klimek L., Kurowska B.

Archives of Foundry Engineering

|

2016

|

Vol. 16, iss. 3

43--48

EN

The paper presents the microstructure and selected properties of ausferritic nodular cast iron annealed at the temperature 520 and 550°C. This choice was dictated by the temperatures used in the practice of nitriding. Nodular graphite in cast iron was obtained with use of Inmold process. Cast iron containing molybdenum and copper ensuring obtaining an ausferrite in the cast iron matrix without the use of heat treatment of castings was tested. The effect of annealing temperature on the microstructure and the kind of fracture of the ausferritic nodular cast iron was presented. The effect of an annealing temperature on hardness, impact strength and the microhardness of ausferritic nodular cast iron matrix was shown too. The lamellar structure of phases in the cast iron matrix after annealing has been ascertained. There has been an increase in hardness of an annealed cast iron and microhardness of its matrix. The reduction in the impact strength of the cast iron annealed at 520 and 550°C was approximately 10-30%. Both an increase in the hardness of cast iron as well as an decrease in its impact strength is probably due to the separation of secondary carbides during the heat treatment.

9

3DP Technology for the Manufacture of Molds for Pressure Casting

Skorulski G.

Archives of Foundry Engineering

|

2016

|

Vol. 16, iss. 3

99--102

EN

The paper presents the use of rapid prototyping technology of three dimensional printing (3DP) to make a prototype shell casting mold. In the first step, for identification purposes, a mold was prepared to enable different alloys to be cast. All molds being cast were designed in a universal CAD environment and printed with the zp151 composite material (Calcium sulfate hemihydrate) with a zb63 binder (2-pyrrolidone). It is designated to be used to prepare colourful models presenting prototypes or casting models and molds. The usefulness of 3DP technology for use with copper alloys, aluminum and zinc was analyzed. The strength of the mold during casting was assumed as a characteristic comparative feature in the material resistance to high temperature, the quality of the resulting casting and its surface roughness. Casting tests were carried out in vacuum – pressure casting. The casting programs applied, significantly increased the quality of castings and enabled precise mold submergence. Significant improvement was noted in the quality compared to the same castings obtained by gravity casting.

10

The Relationship Between the Solidification Parameters and Chemical Composition of Nickel Superalloy IN-713C

Binczyk F., Gradoń J., Cwajna J., Szymszal J.

Archives of Foundry Engineering

|

2014

|

Vol. 14, iss. 4

5--10

EN

The paper presents the results of studies on the development of correlation of solidification parameters and chemical composition of nickel superalloy IN-713C, which is used i.a. on aircraft engine turbine blades. Previous test results indicate significant differences in solidification parameters of the alloy, especially the temperatures Tliq and Tsol for each batch of ingots supplied by the manufacturer. Knowledge of such a relationship has important practical significance, because of the ability to asses and correct the temperatures of casting and heat treatment of casts on the basis of chemical composition. Using the statistical analysis it was found that the temperature of the solidification beginning Tliq is mostly influenced by the addition of carbon (similar to iron alloys). The additions of Al and Nb have smaller but still significant impact. Other alloying components do not have significant effect on Tliq. The temperature Teut is mostly affected by Ni, Ti and Nb. The temperature Tsol is not in any direct correlation with the chemical composition, which is consistent with previous research. The temperature Tsol depends primarily on the presence of non-metallic inclusions present in feed materials and introduced during the melting and casting processes.

11

Investigation of an Advanced Cellulose Profile Used for the Manufacture of Gating Systems

Zawieja Z., Sawicki J., Gumienny G., Sobczyk-Guzenda A.

Archives of Foundry Engineering

|

2014

|

Vol. 14, iss. 3

123--128

EN

The here in paper contains the results of investigations on a new type of cellulose blend used for the manufacture of profiles applied in the process of making gating systems in the foundry industry. A standard cellulose profile was subjected to an experiment. During the experiment the profile was filled with a liquid cast iron and at the same time the temperatures of the liquid metal crystallizing inside the profile were measured as well as the temperature of the outer layer of the profile was controlled. Further, the microstructure of the cast iron, which crystallized out inside the cellulose profile, was analysed and the cellulose, thermally degraded after the experiment, was verified with the use of the chemical analysis method. Moreover, a quality analysis of the original as well as the degraded cellulose profile was run with the use of the FTIR infrared spectroscopy. The presented results revealed that the cellulose blend is aluminium silicate enriched and contains organic binder additives. The cast iron, which crystallized out, tended to have an equilibrium pearlitic structure with the release of graphite and carbides. The generation of disequilibrium ausferrite phases was also observed in the structure.

12

Feeding and Cooling and Time of Thermal Treatment of a Massive Bush Made of the Complex Aluminum Bronze Cast by the Lost Foam

Just P., Pisarek B. P.

Archives of Foundry Engineering

|

2014

|

Vol. 14, iss. 4

39--44

EN

Small additions of Cr, Mo and W to aluminium-iron-nickel bronze are mostly located in phases &kappa i (i=II; III; IV),and next in phase &alpha (in the matrix) and phase γ2. They raise the temperature of the phase transformations in aluminium bronzes as well as the casts’ abrasive and adhesive wear resistance. The paper presents a selection of feeding elements and thermal treatment times which guarantees structure stability, for a cast of a massive bush working at an elevated temperature (650–750°C) made by means of the lost foam technology out of composite aluminium bronze. So far, there have been no analyses of the phenomena characteristic to the examined bronze which accompany the process of its solidification during gasification of the EPS pattern. There are also no guidelines for designing risers and steel internal chill for casts made of this bronze. The work identifies the type and location of the existing defects in the mould’s cast. It also proposes a solution to the manner of its feeding and cooling which compensates the significant volume contraction of bronze and effectively removes the formed gases from the area of mould solidification. Another important aspect of the performed research was establishing the duration time of bronze annealing at the temperature of 750°C which guarantees stabilization of the changes in the bronze microstructure – stabilization of the changes in the bronze HB hardness.

13

Effect of Temperature on Ausferritic Nodular Cast Iron Microstructure

Gumienny G., Klimek L.

Archives of Foundry Engineering

|

2014

|

Vol. 14, iss. 3 spec.

21--24

EN

The work presents the results of the studies of the effect of the temperature on the microstructure of ausferritic nodular cast iron. The ausferrite in the matrix was obtained by way of a specific combination of molybdenum and copper. The cast iron underwent annealing at the temperatures of 520, 550 and 580°C. The work presents the effect of the annealing temperature on the fraction of austenite in the cast iron matrix. The annealed and non-annealed cast iron hardness is given. The work also proves that an increase in the temperature up to 580°C causes a drop in the cast iron hardness.

14

Effect of Electrical Properties of Materials on Effectiveness of Heating Their Systems in Microwave Field

Stachowicz M., Opyd B, Granat K., Markuszewska K.

Archives of Foundry Engineering

|

2014

|

Vol. 14, iss. 2

111--114

EN

In the paper presented are results of a research on influence of electrical and physico-chemical properties of materials being parts of multicomponent and multimaterial systems used in foundry practice on efficiency and effectiveness of microwave heating. Effectiveness of the process was evaluated on the grounds of analysis of interaction between selected parameters of permittivity and loss factor, as well as collective index of energy absorbed, reflected and transmitted by these materials. In the examinations used was a stand of wave guide resonance cavity for determining electrical properties and a stand of microwave slot line for determining balance of microwave power emitted into selected materials. The examinations have brought closer the possibility of forecasting the behaviour of multimaterial systems like e.g. model, moulding sand or moulding box in microwave field on the grounds of various electrical and physico-chemical properties. On the grounds of analysis of the results, possible was selecting a group of materials designed for building foundry instrumentation to be effectively used in electromagnetic field.

15

The use of LPR (logic of plausible reasoning) to obtain information on innovative casting technologies

Kluska-Nawarecka S., Śnieżyński B., Parada W., Lustofin M., Wilk-Kołodziejczyk D.

Archives of Civil and Mechanical Engineering

|

2014

|

Vol. 14, no. 1

25--31

EN

The paper presents a methodology for the application of a formalism of the logic of plausible reasoning (LPR) to create knowledge about a specific problem area. In this case, the methodology has been related to the task of obtaining information about the innovative casting technologies. In the search for documents, formulas created in terms of LPR have a much greater expressive power than the commonly used keywords. The discussion was illustrated with the results obtained using a pilot version of the original information tool.

16

Ductile cast iron obtain by lost foam process and inmold method

Kaczorowski R., Just P., Pacyniak T.

Archives of Metallurgy and Materials

|

2013

|

Vol. 58, iss. 3

823--826

EN

This paper presents a technology of ductile cast iron obtain by lost foam process with use of inmold method. Spheroidization was carried out using master alloy in an amount of 1.5% by mass on casting iron. Research the influence of the gating system configuration and the shape of the reaction chamber, the degree of spheroidization cast iron, which estimated based on the shape of the graphite. Research have shown that the greatest impact on the degree of spheroidization has cast the infusion position relative to the casting inlet and the reaction chamber, and the shape of the reaction chamber.

PL

W pracy przedstawiono technologię otrzymywania odlewów z żeliwa sferoidalnego metodą inmold z wykorzystaniem procesu pełnej formy. Sferoidyzację prowadzono z użyciem zaprawy sferoidyzująco-modyfikującej w ilości 1,5% na masę sferoidyzowanego żeliwa. Przeprowadzono badania wpływu konfiguracji układu wlewowego oraz kształtu komory reakcyjnej na stopień sferoidyzacji żeliwa, który określono na podstawie wskaźnika kształtu grafitu. Badania wykazały, że największy wpływ na stopień sferoidyzacji żeliwa ma położenie wlewu doprowadzającego względem odlewu i komory reakcyjnej, oraz kształt komory reakcyjnej.

17

The silumin coat structure on alloy ductile iron

Szymczak T.

Archives of Foundry Engineering

|

2013

|

Vol. 13, iss. 1

119--124

EN

The work presents the research results of the silumin coat structure applied on the carbidic alloy ductile iron with the metal matrix: pearlitic, bainitic and martensitic. The coats were made in the AlSi5 silumin bath at the temperature tk = 750±5ºC. The holding time of cast iron element in the bath was \tau = 180s. Irrespective of the kind of tested ductile iron the obtained coat consisted of three layers with a different phase composition. The first layer from the cast iron ground “g1” is built from Fe4CSi carbide which contains selected alloy additives of the cast iron. On it the second layer “g1” crystallizes. It consists of the AlFeSi inter-metallic phase which can appear in its pure form or contain a small quantity of the alloy additives of the cast iron. The last external part of the layer “g2” mainly consists of the hypo-eutectic phases of silumin. The AlFeSi inter-metallic phases in the form of free precipitations with a lamellar or faceted morphology can also appear there. These phases also can contain a small quantity of the alloy additives of the cast iron. More than that, in all the layers of the coat there are graphite precipitations. The phenomenon of graphite movement to the coat is caused by intensive dissolving of the cast iron element surface by the aluminum of the silumin bath.

18

Optimization of master alloy amount and gating system design for ductile cast iron obtain in lost foam process

Just P., Kaczorowski R., Pacyniak T.

Archives of Foundry Engineering

|

2013

|

Vol. 13, iss. 3

43--46

EN

The paper presents the optimization of master alloy amount for the high nodular graphite yield (80-90%) in cast iron obtain in lost foam process. The influence of the gating system configuration and the shape of the reaction chamber, the degree of spheroidisation cast iron was examined. Research has shown that the, optimal of master alloy amount of 1.5% by mass on casting iron. The degree of spheroidisation is also influenced by the gating system configuration. The best spheroidisation effect was obtained for liquid cast iron was fed into the reaction chamber from the bottom and discharged from the top.

19

Wpływ procesu azotonasiarczania na zmianę wymiarów czopa wału korbowego odlanego metodą lost foam ze sferoidyzacją „inmold”

Binienda M., Just P., Komorowski J., Pokrzywa M., Wołowiec E.

Czasopismo Techniczne. Mechanika

|

2012

|

R. 109, z. 9-M

33--39

PL

W artykule przedstawiono sposób modyfikacji warstwy wierzchniej czopu korbowego metodą azotonasiarczania w celu polepszenia jego odporności korozyjnej, wyeliminowania możliwości zacierania wraz z uzyskaniem wysokiej trwałości elementu dzięki podniesieniu wytrzymałości na ścieranie poprzez zmniejszenie współczynnika tarcia a także zwiększenie twardości powierzchni. Wał korbowy z żeliwa sferoidalnego został odlany w technologii lost foam z sferoidyzacja inmold, obrobiony cieplnie, a następnie poddany obróbce cieplno-chemicznej. Zbadano własności warstwy azotonasiarczonej oraz przyrost wymiarów czopu powstały w wyniku obróbki cieplno-chemicznej.

EN

The paper shows how to modify the surface layer of the crank stud sulfonitriding method in order to improve its corrosion resistance, and eliminate the possibility of scuffing of the element to obtain a high durability by improving the abrasion resistance by decreasing the coefficient of friction and increasing the surface hardness. Ductile iron crankshaft was cast in the lost foam technology of spheroidization inmold, heat treated and then subjected to thermochemical treatment.

20

The structure of the silumin coat on alloy cast steels

Szymczak T.

Archives of Foundry Engineering

|

2012

|

Vol. 12, iss. 2

215-220

EN

The work presents the analysis results of the structure of the coat obtained by dipping in silumin AlSi5 of two grades of alloy cast steel: GX6CrNiTi18-10 (LH18N9T) and GX39Cr13 (LH14). The temperature of the silumin bath was 750-5 C, and the hold-up time of the cast steel element [...] = 180 s. The absolute thickness of the coat obtained in the given conditions was g = 104 [...] on cast steel GX6CrNiTi18-10 and g = 132 [...] on GX39Cr13. The obtained coat consisted of three layers of different phase structure. The first layer from the base [...] was constructed of the phase AlFe including Si and alloy additives of the tested cast steel grades: Cr and Ni (GX6CrNiTi18-10) and Cr (GX39Cr13). The second layer [...] of intermetallic phases AlFe which also contains Si and Cr crystallizes on it. The last, external layer 'g2' of the coat consists of the silumin containing the intermetallic phases AlFeSi which additionally can contain alloy additives of the cast steel. It was shown that there were no carbides on the coat of the tested cast steels which are the component of their microstructure, as it took place in the case of the coat on the high speed steels.