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1
Content available Study of the Influence of Additions on the Formation of Microstructure of Al-Zn-Mg-Cu Alloys
Pisarek B. P., Czekaj E., Pacyniak T.
Archives of Foundry Engineering
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2018
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Vol. 18, iss. 4
39--44
EN
The article presents the investigations of 7xxx aluminium alloys performed by the method of thermal and derivational analysis. The studies made it possible to identify the effect of the changes in the Cu concentration, the total Zn and Mg weight concentrations and the Zn/Mg weight concentration ratio on their crystallization process: the cooling as well as the kinetics and dynamics of the thermal process of cooling and crystallization. Metallographic studies were performed on the microstructure of the examined alloys and their HB hardness was measured. The evaluation of the changes was presented in reference to the model alloys EN AW-7003 and EN AW-7010, whose microstructure under the conditions of thermodynamic equilibrium are described by the phase diagrams: Al-Zn-Mg and Al-Zn-Mg-Cu. The performed investigations confirmed that the hardness HB of the examined alloys is mainly determined by the reinforcement of the matrix αAl by the introduced alloy additions and the presence of phases Θ(Al2Cu) and S(Al2CuMg) rich in copper, as well as η(MgZn2), in the examined alloys' microstructure. The increase of the amount of intermetallic phases precipitated in the microstructure of the examined alloys is caused, beside Cu, by the characteristic change of Zn wt. concentration and Mg. It was proposed that the process of one-stage thermal treatment of the examined alloys be introduced at a temperature of up to tJ-20 °C, which will prevent the exceedance of the solidus temperature.
2
Content available Microstructural and Tribological Characterization of Aluminium Bronzes with Additions of Si and Cr
Pisarek B. P., Kowalski B., Atapek H., Polat Ş., Tüfekçi T.
Archives of Foundry Engineering
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2018
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Vol. 18, iss. 1
93--98
EN
The article presents the investigation results of the crystallization (performed by means of the TDA method) and the microstructure of complex aluminium bronzes with the content of 6% Al, 4% Fe and 4% Ni, as well as Si additions in the scope of 1–2% and Cr additions in the scope of 0.1–0.3%, which have not been simultaneously applied before. For the examined bronze, the following tests were performed: hardness HB, impact strength (KU2). For bronze CuAl6Fe4Ni4Si2Cr0.3, characterizing in the highest hardness, wear tests were conducted with dry friction and the dry friction coefficient. The investigations carried out by means of the X-ray phase analysis demonstrated the following phases in the microstructure of this bronze: αCu, γ2 and complex intermetallic phases based on iron silicide type Fe3Si (M3Si M={Fe,Cr,…}). Compared to the normalized aluminium bronzes (μ=0.18–0.23), the examined bronze characterizes in relatively low wear and lower friction coefficient during dry friction (μ=0.147±0.016).
3
Content available Effect of Intensive Cooling of Alloy AZ91 with a Chromium Addition on the Microstructure and Mechanical Properties of the Casting
Rapiejko C., Pisarek B., Pacyniak T.
Archives of Metallurgy and Materials
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2017
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Vol. 62, iss. 4
2199--2203
EN
The work presents the results of the investigations of the effect of intensive cooling of alloy AZ91 with an addition of chromium on the microstructure and mechanical properties of the obtained casts. The experimental castings were made in ceramic moulds preliminarily heated to 180°C, into which alloy AZ91 with the addition was poured. Within the implementation of the research, a comparison was made of the microstructure and mechanical properties of the castings obtained in ceramic moulds cooled at room temperature and the ones intensively cooled in a cooling liquid. The kinetics and dynamics as well as the thermal effects recorded by the TDA method were compared. Metallographic tests were performed with the use of an optical microscope and the strength properties of the obtained castings were examined: UTS (Rm), elongation (A%), and HB hardness.
4
Content available Effect of Vanadium and Molybdenum on the Crystallization, Microstructure and Properties of Hypoeutectic Silumin
Szymczak T., Gumienny G., Pacyniak T.
Archives of Foundry Engineering
|
2015
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Vol. 15, iss. 4
81--86
EN
The paper presents the results of hypoeutectic silumin 226 grade and silumin produced on its basis through the addition of V and Mo. Vanadium and molybdenum were added as the preliminary alloy AlV10 and AlMo8 in an amount providing the concentration of 0.1; 0.2; 0.3 and 0.4% V and Mo. TDA curves of tested silumins were presented; regardless of the chemical composition there were similar thermal effects. Pressure castings microstructure research revealed the presence in silumins with the addition of V and Mo phases do not occur in silumin without these additives. These phases have a morphology similar to the walled, and their size increases with increasing concentration of V and Mo. The size of the precipitates of these phases silumin containing 0.1% V and Mo does not exceed 10 microns, while 0.4% of the content of these elements increases to about 80 microns. Tests of basic mechanical properties of silumins were carried out. It has been shown that the highest values of tensile strength Rm = 295 MPa and elongation A = 4.2% have silumin containing approximately 0.1% V and Mo. Increasing concentrations of these elements causes a gradual lowering of the Rm and A values.
5
Content available Effect of Tungsten and Molybdenum on the Crystallization, Microstructure and Properties of Silumin 226
Szymczak T., Gumienny G., Pacyniak T., Walas K.
Archives of Foundry Engineering
|
2015
|
Vol. 15, iss. 3
61--66
EN
The work presents the results of the examinations of silumin 226 as well as a silumin produced on its basis containing a W and Mo addition introduced in the amount of 0.1; 0.2; 0.3 and 0.4% of both elements simultaneously. Investigations of the crystallization process of the silumins by the TDA method were conducted. Also, a microscopic analysis of their microstructure was performed and their basic mechanical properties were determined. Microstructure tests were made on casts produced in an TDA sampler as well as by the pressure method. The investigations exhibited a change in the course of crystallization of the silumin containing 0.3 and 0.4% W and Mo with respect to silumin 226 and the silumin with the addition of 0.1 and 0.2%. The presence of additional phases which did not occur in the case of lower addition contents was established in the silumin containing 0.3-0.4% W and Mo, regardless of the applied casting technology. The tests showed the possibility of increasing the tensile strength Rm, the proof stress Rp0,2 and the unit elongation A of the silumin as a result of a simultaneous introduction of the W and Mo addition. The highest values of Rm, Rp0,2 and A were obtained in the silumins with the additions of these elements within the range of 0.1-0.2% each.
6
Content available Effect of Chromium on the Solidification Process and Microstructure of Vermicular Graphite Cast Iron
Gumienny G., Dondzbach M., Kacprzyk B.
Archives of Foundry Engineering
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2015
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Vol. 15, iss. 3
29--34
EN
The paper presents the results of studies of the effect of chromium concentration on the solidification process, microstructure and selected properties of cast iron with vermicular graphite. The vermicular graphite cast iron was obtained by an Inmold process. Studies covered the cast iron containing chromium in a concentration at which graphite is still able to preserve its vermicular form. The effect of chromium on the temperature of eutectic crystallization and on the temperature of the start and end of austenite transformation was discussed. The conditions under which, at a predetermined chromium concentration, the vermicular graphite cast iron of a pearlitic matrix is obtained were presented, and the limit concentration of chromium was calculated starting from which partial solidification of the cast iron in a metastable system takes place. The effect of chromium on the hardness of cast iron, microhardness of individual phases and surface fraction of carbides was disclosed.
7
Content available An Application for Infrared Camera in Analyzing of the Solidification Process of Al-Si Alloy
Władysiak R., Kozuń A.
Archives of Foundry Engineering
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2015
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Vol. 15, iss. 3
81--84
EN
The paper presents the results of the crystallization process of silumin by the TDA thermographic method and the results of the cast microstructure obtained in the sampler TDA-10, that was cooling down in ambient air. The study was conducted for silumin AlSi11 unmodified. The work demonstrated that the use of thermal imaging camera allows for the measurement and recording the solidification process of silumin. Thermal curve was registered with the infrared camera and derivative curve that was calculated on the base of thermal curve have both a very similar shape to adequate them TDA curves obtained from measurements using a thermocouple. Test results by TDA thermographic method enable quantitative analysis of the kinetics of the cooling and solidification process of neareutectic silumin.
8
Content available Analysis of AM60 and AZ91 Alloy Crystallisation in Ceramic Moulds by Thermal Derivative Analysis (TDA)
Rapiejko C., Pisarek B., Czekaj E., Pacyniak T.
Archives of Metallurgy and Materials
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2014
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Vol. 59, iss. 4
1449--1455
EN
The work presents the test results of the crystallisation and cooling of magnesium alloys: AM60 and AZ91, with the use of the TDA method. The tested alloys were cast into ceramic shells heated up to 180°C, produced according to the technology of the shell production in the investment casting method. The TDA method was applied to record and characterize the thermal effect resulting from the phase transformations occurring during the crystallisation of magnesium alloys. The kinetics and dynamics of the thermal processes of the crystallisation of AM60 and AZ91 in the ceramic shells were determined. Metallographic tests were performed with the use of an optical microscope as well as scanning microscopy, together with the EDS chemical analysis of the phases present in the tested casts. A comparison of these test results with the thermal effect recorded by way of the TDA method was made.
PL
W pracy przedstawiono wyniki badań krystalizacji i stygnięcia stopów magnezu: AM60 i AZ91 przy użyciu metody ATD. Badane stopy zalewano do form ceramicznych podgrzanych do temperatury 180°C, wykonanych zgodnie z technologią wytwarzania form w metodzie traconych modeli. Przy pomocy metody ATD zarejestrowano i wyznaczono charakterystyczne efekty cieplne wynikające z przemian fazowych zachodzących podczas krystalizacji badanych stopów magnezu. Określono kinetykę i dynamikę procesów cieplnych krystalizacji stopów AM60 i AZ91 w formach ceramicznych. Przeprowadzono badania metalograficzne przy pomocy mikroskopu optycznego oraz mikroskopii skaningowej wraz z analizą chemiczną EDS występujących faz w badanych odlewach. Porównano wyniki tych badań z efektami cieplnymi zarejestrowanymi metodą ATD.
9
Content available Selected Aspects of Nitrogen Refinement of Silumin 226
Szymczak T., Gumienny G., Pacyniak T.
Archives of Foundry Engineering
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2014
|
Vol. 14, iss. 3
99--102
EN
The work presents the results of the investigations of the effect of the nitrogen (N2) refining time „traf” and the gas output on the course of the crystallization process, the microstructure and the gassing degree of silumin 226 used for pressure casting. The refinement of the examined silumin was performed with the use of a device with a rotating head. The crystallization process was examined by way of thermal analysis and derivative analysis TDA. The performed examinations showed that the prolongation of the N2 refining time causes a significant rise of the temperature of the crystallization end of the silumin, „tL”, as well as a decrease of its gassing degree, „Z”. An increase of the nitrogen output initially causes an increase of the temperature „tL” and a drop of the gassing degree „Z”, which reach their maximal values with the output of 20 dm3/min. Further increase of the output causes a decrease of the value „tL” and an increase of „Z”. The examined technological factors of the refining process did not cause any significant changes in the microstructure of silumin 226.
10
Content available Effect of the Hold Time and Temperature on Characteristic Quantities of TDA Curves
Szymczak T., Gumienny G., Pacyniak T.
Archives of Foundry Engineering
|
2014
|
Vol. 14, iss. 1
113--116
EN
This paper presents the effect of the temperature and hold time in the holding furnace of 226 silumin on the characteristic quantities of TDA curves. The temperature of phase transformations and the cooling rate were tested. It has been shown that increasing both the hold time and the temperature in the holding furnace cause the decreasethe end ofα+Al9Fe3Si2+β and α+Al2Cu+β ternary eutectics crystallization temperature in the tested silumin. This is due to the fact an increase in amounts of impurities as a result of reacting the liquid alloy with the gases contained in the air. It has been shown, however, that examined technological factors of the metal preparation do not cause systematic changes in the cooling rate.
11
Content available Analysis of the Crystallization of AZ91 Alloy by Thermal and Derivative Analysis Method Intensively Cooled in Ceramic Shell
Rapiejko C., Pisarek B., Czekaj E., Pacyniak T.
Archives of Foundry Engineering
|
2014
|
Vol. 14, iss. 1
97--102
EN
The work presents the test result of the influence of cooling rate on the microstructure of AZ91 alloy, Vickers micro-hardness and Brinell hardness. Studies cooling and crystallization of AZ91 alloy was cast into the ceramic shells pre-heated to 180°C and then air-cooled at ambient temperature or intensively super cooled in the liquid coolant. The TDA method was applied to record and characterize the thermal effect resulting from the phase transformations occurring during the crystallization of AZ91 alloy. The kinetics and dynamics of the thermal processes of crystallization of AZ91 alloy in the ceramic shells were determined. Metallographic tests were performed with the use of an optical microscope. A comparison of these test results with the thermal effect recorded by way of the TDA method was made. Influence of cooling rate of AZ91 on HV0, 01 micro-hardness and Brinell hardness alloy was examined.
12
Content available Technological aspects of low-alloyed cast steel massive casting manufacturing
Szajnar J., Studnicki A., Głownia J., Kondracki M., Suchoń J., Wróbel T.
Archives of Foundry Engineering
|
2013
|
Vol. 13, iss. 4
97--102
EN
In the paper authors have undertaken the attempt of explaining the causes of cracks net occurrence on a massive 3-ton cast steel casting with complex geometry. Material used for casting manufacturing was the low-alloyed cast steel with increased wear resistance modified with vanadium and titanium. The studies included the primary and secondary crystallization analysis with use of TDA and the qualitative and quantitative analysis of non-metallic inclusions.
13
Content available Crystallization of low-alloyed construction cast steel modified with V and Ti
Studnicki A., Kondracki M., Szajnar J., Wróbel T.
Archives of Foundry Engineering
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2013
|
Vol. 13, iss. 3
92--96
EN
In this paper crystallization studies of low-alloyed construction cast steel were presented for different additions of chromium, nickel and molybdenum modified with vanadium and titanium. Studies were conducted using developed TDA stand, which additionally enabled evaluation of cooling rate influence on crystallization process of investigated alloys.
14
Content available remote TDA method application to austenite transformation in nodular cast iron with carbides assessment
Gumienny G.
Archives of Foundry Engineering
|
2011
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Vol. 11, iss. 3
159-166
EN
In this paper the possibility of TDA method using to austenite transformation in nodular cast iron with carbides assessment is presented. Studies were conducted on cast iron with about 2% molybdenum and 0,70% to 4,50% nickel. On diagrams, where TDA curves are presented, on time axis a logarithmic scale was applied. It has not been used up to now. It was found, that during cooling and crystallization of cast iron in TDA probe, on the derivative curve there is a slight thermal effect from austenite to upper bainite or martensite transformation. Depending on nickel concentration austenite upper bainite transformation start temperature changed (Bus), while MS temperature was independent of it. An influence of nickel on eutectic transformation temperature in nodular cast iron with carbides was determined too.
15
Content available remote Chromium and copper influence on the nodular cast iron with carbides microstructure
Gumienny G.
Archives of Foundry Engineering
|
2010
|
Vol. 10, iss. 4
47--54
EN
In this paper chromium to 1,00% and copper to 1,50% influence at constant molybdenum content of about 1,50% on the nodular cast iron with carbides microstructure has been presented. It was found, that as a result of synergic addition of above-mentioned elements there is the possibility obtaining an ausferrite in nodular cast iron with carbides castings. Conditions have been given, when in nodular cast iron with carbides at cooling at first in the form, then air-cooling austenite transformation to upper bainite, its mixture with lower bainite, martensite or ausferrite takes place. Transformations proceed during cooling and the crystallization of cast iron have been determined and the casting hardness has been presented.
16
Content available remote Bainitic-martensitic nodular cast iron with carbides
Gumienny G.
Archives of Foundry Engineering
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2010
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Vol. 10, iss. 2
63--68
EN
In this paper the possibility obtaining of upper bainite, lower bainite and martensite or their mixture in nodular cast iron with carbides has been presented. Conditions have been given, when in nodular cast iron with carbides for cooling at first in the form, then air-cooling austenite transformation to upper bainite, its mixture with lower bainite and martensite takes place. Transformations proceed during cooling and the crystallization of cast iron have been determined and the casting hardness has been presented.
17
Content available remote Bainite obtaining in cast iron with carbides castings
Pietrowski S., Gumienny G.
Archives of Foundry Engineering
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2010
|
Vol. 10, iss. 1
109-114
EN
In these paper the possibility of upper and lower bainite obtaining in cast iron with carbides castings are presented. Conditions, when in cast iron with carbides castings during continuous free air cooling austenite transformation to upper bainite or its mixture with lower bainte proceeds, have been given. A mechanism of this transformation has been given, Si, Ni, Mn and Mo distribution in the eutectic cell has been tested and hardness of tested castings has been determined.
18
Content available remote Plaster mould casting process of AlSi11 alloy
Władysiak R., Pawlak M.
Archives of Foundry Engineering
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2009
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Vol. 9, iss. 4
225-232
EN
The paper presents the results of the crystallization and cooling process of AlSi11 silumin in the plaster mould with TDA method and describes the impact of the preparation of plaster mould and liquid silumin on received microstructure and quality of casting. The effect of the pouring temperature of silumin on porosity and filling of mould cavity was investigated. The nature and rate of change of temperature in casting and the formation of the microstructure was shown by means thermal and derivative curves. Through the use of control samples in range of a thickness of 0.5 - 4 mm confirmed the possibility of obtaining thin-walled silumin castings in pre-heated before plaster moulds. It has been proved that changing the parameters of pre-treatment moulds of gypsum, the pouring temperature and modification of silumin you can control the crystallization process, obtained microstructure and properties Rm, RP02 and HB.
19
Content available remote Bainitic nodular cast iron with carbides obtaining with use of Inmold method
Gumienny G.
Archives of Foundry Engineering
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2009
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Vol. 9, iss. 3
243-248
EN
In these paper bainitic nodular cast iron with carbides as-cast obtaining has been presented. This cast iron has been obtained with use of Inmold method. It was shown, that there is the possibility of bainite and carbides obtaining in cast iron with Mo and Ni for studied chemical composition.
20
Content available remote Nodular cast iron and casting monitoring
Pietrowski S., Rapiejko C.
Archives of Foundry Engineering
|
2008
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Vol. 8, iss. 3
181-184
EN
In this paper quality monitoring of nodular cast iron and casting made of it is presented. A control system of initial liquid cast iron to spheroidization, after spheroidization and inoculation with using of TDA method was shown. An application of an ultrasonic method to assessment of the graphite form and the metal matrix microstructure of castings was investigated.
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