Wyniki wyszukiwania - BazTech

1

Effect of Intensive Cooling of Alloy AC-AlSi7Mg with Alloy Additions on Microstructure and Mechanical Properties

Pisarek B., Rapiejko C., Pacyniak T.

Archives of Metallurgy and Materials

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2019

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Vol. 64, iss. 2

677--681

EN

The work presents results of the investigations of effect of intensive cooling of alloy AC-AlSi7Mg with alloy additions on microstructure and mechanical properties of the obtained casts. The experimental casts were made in ceramic molds preliminarily heated to 180°C, into which AC-AlSi7Mg with alloy additions was poured. Within implementation of the research, a comparison was made of the microstructure and mechanical properties of the casts obtained in ceramic molds cooled at ambient temperature and the ones intensively cooled in a cooling liquid. Kinetics and dynamics thermal effects recorded by the TDA method were compared. Metallographic tests were performed with the use of optical microscope and strength properties of the obtained casts were examined: UTS, Elongation and HB hardness.

2

Change of the grade line of bridges constructed with cantilever concreting technology

Machelski C., Pisarek B.

Architecture Civil Engineering Environment

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2018

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Vol. 11, no. 2

65--72

EN

The cantilever concreting technology is one of modern methods of constructing the concrete long-span bridges. The fundamental features of this method are saving of materials and of construction costs (especially of scaffolding and of formwork) and first of all a possibility of carrying out the construction of the span in many places at the same time. The negative feature of these bridges is a large long-term deflection of the span, as a result of rheological processes in the concrete and in the pre-tensioning steel. Deflection measurements at the mid-span indicate a visible lowering of the grade line of the bridge span, already after few years of service. In this paper the deflection w(t) is represented as a function of the service time of the bridge structure, calibrated by the results of monitoring of the bridge deflection. Analyses presented in this paper will be used to develop rheological models of behavior of the concrete and of the pre-tensioning steel.

PL

Technologia betonowania wspornikowego jest jedną z nowoczesnych metod konstruowania betonowych mostów o dużej rozpiętości. Podstawowymi cechami tej metody są oszczędność materiałów i kosztów budowy (zwłaszcza rusztowań i szalunków), a przede wszystkim możliwość wykonywania poszczególnych przęseł w tym samym czasie. Negatywną cechą tych mostów jest duże długotrwałe ugięcie mostu powstające w wyniku procesów reologicznych w betonie i stali naprężającej. Pomiary ugięć w połowie rozpiętości wskazują na widoczny ich wzrost już po kilku latach użytkowania. W niniejszym artykule ugięcie w(t) przedstawiono w funkcji czasu użytkowania konstrukcji mostu. Wartości te skalibrowano na podstawie wyników monitoringu ugięć mostu. Analizy przedstawione w niniejszym artykule posłużą do opracowania reologicznych modeli zachowania betonu i stali naprężającej.

3

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

Effect of intensive cooling of alloy AM60 with chromium and vanadium additions on cast microstructure and mechanical properties

Rapiejko C., Pisarek B., Pacyniak T.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 1

309--314

EN

The work presents the results of the investigations of the effect of intensive cooling of alloy AM60 with additions of chromium and vanadium on the microstructure and mechanical properties of the obtained casts. The experimental casts were made in ceramic moulds preliminarily heated to 180°C, into which alloy AM60 with the additions was poured. Within the implementation of the research, a comparison was made of the microstructure and mechanical properties of the casts obtained in ceramic moulds cooled at ambient temperature and the ones intensively cooled in a cooling liquid. The kinetics and dynamics 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 casts were examined: UTS(Rm), elongation (A%), and HB hardness.

5

Tribological Characterization of Al-bronzes Used as Mold Materials

Atapek Ş. H., Aktaş Çelik G., Polat Ş., Pisarek B.

Archives of Foundry Engineering

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2017

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Vol. 17, iss. 4

7--12

EN

Among the copper based alloys, Cu-Al-X bronzes are commonly used as mold materials due to their superior physical and chemical properties. Mold materials suffer from both wear and corrosion, thus, it is necessary to know which one of the competitive phenomenon is dominant during the service conditions. In this study, tribo-corrosion behavior of CuAl10Ni5Fe4 and CuAl14Fe4Mn2Co alloys were studied and electrochemical measurements were carried out using three electrode system in 3.5 % NaCl solution in order to evaluate their corrosion resistance. In tribo-corrosion tests, alloys were tested against zirconia ball in 3.5 % NaCl solution, under 10N load with 0.04 m/s sliding speed during 300 and 600 m. The results indicate that (i) CuAl10Ni5Fe4 alloy is more resistant to NaCl solution compared to CuAl14Fe4Mn2Co alloy that has major galvanic cells within its matrix, (ii) although CuAl10Ni5Fe4 alloy has lower coefficient of friction value, it suffers from wear under dry sliding conditions, (iii) as the sliding distance increases, corrosion products on CuAl14Fe4Mn2Co surface increase at a higher rate compared to CuAl10Ni5Fe4 leading to a decrease in volume loss due to the lubricant effect of copper oxides.

6

Szlifowanie brązu krzemowego BK31 na szlifierce kłowej do wałków

Kruszyński B., Lajmert P., Stachurski W., Zgórniak P., Pisarek B., Pacyniak T.

Mechanik

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2015

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R. 88, nr 8-9CD1

231--236

PL

W artykule zaprezentowano badania szlifowania brązu krzemowego BK31 dla różnych warunków obróbki. Próby wykonano na szlifierce kłowej do wałków z zastosowaniem dwóch ściernic. Przeprowadzono analizę wpływu warunków obróbki na zmiany składowych sił szlifowania, temperatury szlifowania oraz emisji akustycznej. W końcowej części pracy przedstawiono wpływ warunków obróbki na chropowatość szlifowanych przedmiotów.

EN

In the paper grinding process has been studied in the machining of silicon bronze BK31 alloy for different grinding conditions. Grinding tests has been done on cylindrical grinding machine with the use of two kinds of grinding wheels. An analysis was carried out to investigate the influence of grinding conditions on the grinding force components, grinding temperatures and acoustic emission signal. In the end, the influence of grinding conditions on workpiece surface roughness, is presented.

7

Effect of Cr and V Alloy Additions on the Microstructure and Mechanical Properties of Am60 Magnesium Alloy

Rapiejko C., Pisarek B., Pacyniak T.

Archives of Metallurgy and Materials

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2014

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Vol. 59, iss. 2

761--765

EN

The paper presents the results of the investigation of the effect of Cr and/or V alloy additions on the microstructure and mechanical properties of the magnesium AM60 alloy. The examinations are performed within the frames of a project aiming at the elaboration of an experimental and industrial technology of producing constructively complex elements of machines and devices made of magnesium alloys with the method of investment casting. It has been proven that small numbers of Cr and V alloy additions improve the strength properties: Rm, A%, and the hardness HB of the obtained casts. The experimental casts were made in ceramic molds.

PL

W pracy przedstawiono wyniki badań wpływu dodatków stopowych Cr i/lub V na mikrostrukturę oraz właściwości mechaniczne stopu magnezu AM60. Badania prowadzone są w ramach projektu, którego celem jest opracowanie technologii doświadczalnej i przemysłowej wytwarzania złożonych konstrukcyjnie elementów maszyn i urządzeń ze stopów magnezu metodą wytapianych modeli. Wykazano, że niewielkie ilości dodatków stopowych Cr i V poprawiają właściwości wytrzymałościowe: Rm, A%. oraz twardość HB otrzymanych odlewów. Odlewy doświadczalne wykonano w formach ceramicznych.

8

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

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

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2014

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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.

10

Brązy aluminiowe z dodatkiem Cr, Mo i/lub W o wysokiej odporności na zużycie

Pisarek B.

Zeszyty Naukowe. Rozprawy Naukowe / Politechnika Łódzka

|

2013

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Z. 441

1--332

PL

Przedstawiono wyniki badań: procesu tworzenia się mikrostruktury metodą analizy termicznej i derywacyjnej (ATD), mikrostruktury, właściwości technologicznych i odporności na zużycie ścierne i adhezyjne, właściwości mechanicznych w odlewach z formy piaskowej w stanie surowym i po obróbce cieplnej brązów zawierających około 10% Al 5% Fe i 5% Ni i dodatki Cr, Mo, W wprowadzane pojedynczo lub jednocześnie oraz dodatki Cr, Mo, W wprowadzane jednocześnie z Si lub C. Mikrostrukturę brązów badano wykorzystując metody analizy na: mikroskopie świetlnym, elektronowym mikroskopie skaningowym (SEM), mikroanalizatorze rentgenowskim (EDS) i dyfraktometrze rentgenowskim (XRD). Przeprowadzono badania odporności na zużycie ścierne na papierze ściernym o ziarnistości P40 i adhezyjne na hartowanej przeciwpróbce ze stali C45+QT wg PN-EN 10083-2:2008 (Stale do ulepszania cieplnego), (bez smarowania i ze smarowaniem olejem), względem przemysłowego brązu Cu-A110Fe5Ni5-C wg PN-EN 1982:2010 (Miedź i stopy miedzi - Gąski i odlewy). W wyniku badań określono: skład fazowy, kolejność krystalizujących faz bądź ich układów. Zidentyfikowano wpływ dodatków Cr, Mo, W, C i Si na punkty charakterystyczne na krzywych wyznaczanych metodą ATD i określane przy ich pomocy wielkości opisujące proces krystalizacji i przemian fazowych w stanie stałym brązu, takie jak: temperatura brązu t, kinetyka procesu krystalizacji dt/dτ, dynamika procesu krystalizacji d2τ/dτ2 i Z = tg(α) ≈ d2t/dτ2, czas τ oraz zakresy czasu trwania procesów SK. Określono przebieg i mechanizm przemian strukturalnych zachodzących podczas obróbki cieplnej. W wyniku badań określono zmiany właściwości technologicznych nowych brązów (porowatość, skurcz objętościowy, skurcz liniowy). Określono zmiany właściwości mechanicznych (Rm, Rpo0,2, A5, HB, μHV) wywołanych stosowanym rodzajem: dodatków stopowych, obróbki cieplnej i ustalono zależności pomiędzy mikrostrukturą a właściwościami mechanicznymi brązów w temperaturze otoczenia. Stwierdzono, że nowe brązy złożone charakteryzują się dobrymi właściwościami wytrzymałościowymi i technologicznymi. Brązy z dodatkiem Mo lub W charakteryzują się dwukrotnie niższym zużyciem od brązu referencyjnego CuAl10Fe5Ni5-C. Wprowadzone jednocześnie dodatki do brązu w układach: MoSi, WSi czy też MoC lub WC również podwyższają odporność na zużycie ścierne nowych brązów, lecz w mniejszym stopniu niż w przypadku wprowadzenia tylko Mo lub W. Wszystkie analizowane dodatki stopowe podwyższają odporność nowych brązów na zużycie adhezyjne (bez smarowania). W kolejności malejącego wpływu na wzrost odporności na zużycie adhezyjne (bez smarowania) wpływają dodatki w następujących układach: CrSi, MoSi, WSi, CrMoWSi, następnie: Cr, Mo, W, CrMoW i na koniec CrC, MoC, WC, CrMoWC. Przy smarowaniu olejem badane brązy charakteryzowały się porównywalną odpornością na zużycie adhezyjne do brązu CuAl10Fe5Ni5-C. Opracowano teoretyczne i technologiczne podstawy sterowania mikrostrukturą brązów warunkujące umocnienie ich mikrostruktury w wyniku krystalizacji: faz międzymetalicznych bogatych przede wszystkim w pierwiastki: Cr, Mo, W; węgliki (Cr, Mo, W, C), krzemki (Cr, Mo, W, Si) i/lub fazy K oraz przemian fazowych w stanie stałym nowych brązów aluminiowych z dodatkami Cr, Mo, W, C i Si. Umożliwia to opracowanie odlewniczych wysokojakościowych brązów aluminiowych złożonych o korzystniejszych właściwościach użytkowych, zarówno w stanie lanym, jak i po obróbce cieplnej. Pozwala to na wydłużenie czasu eksploatacji odlewów wykonanych z tych brązów poprzez zmniejszenie intensywności zużywania się elementów konstrukcyjnych.

EN

The hereby thesis presents processes describing how a microstructure is formed with the use of thermal and derivative (TDA) analyses. It also demonstrates research carried out on the microstructure itself explaining its technological properties and its wear and adhesive resistance as well as its mechanical characteristics in molded sand casts in raw state, and bronze containing approximately 10% Al, 5% Fe and 5% Ni and additions such as Cr, Mo and W added separately or simultaneously, and additions as Cr, Mo and W added simultaneously with Si or C. The bronzes microstructure was examined employing methods such as optical microanalysis, scanning electron microanalysis (SEM), roentgen microanalysis (EDS) and X-ray diffraction (XRD). The experimentation concerned resistance to friction prepared on sandpaper with P40 granularity, and resistance to adhesives prepared on a counter-sample made of steel (C45+QT) according to PN-EN 10083-1:2008 (Steels for toughening), (with and without oiling) relatively to commercial bronze CuAl10Fe5M5-C according to PN-EN 1982:2010 (Copper and its alloys - pig sows and casts). The study allowed to define phase composition, the order of crystallization phases or their systems. What is more, the research enabled to identify the impact of additions Cr, Mo, W, C and Si on the characteristic points on curves as well as quantities which were both determined on the basis of the TDA method. The quantities describe crystallization process and phases transformation in solid state of bronze such as bronze temperature t, crystallization process kinetics dt/dτ, crystallization process dynamics d2t/dτ2 i Z = tg(α) ≈ d2t/dτ2, time τ, and time scopes of processes’ duration SK. The study allowed for describing the course and mechanism of structural transformations occurring during heat treatment. As a result of the research technological properties transformations of new bronzes such as porosity, contraction in volume as well as linear contraction were defined. Furthermore, there were changes of mechanical properties (Rm, Rpo0,2, A5, HB, μHV) determined which are caused by employed type of alloy additions, heat treatment, which led to establish the relationships between microstructure and mechanical properties of bronzes in ambient temperature. Thanks to the research it was stated that new complex bronzes are distinguished by their resistant and technological properties. Bronzes’ enriched with Mo and W wear resistance is twice as less than in case of referential bronzes CuAl10Fe5Ni5-C. Additions added simultaneously to a bronze in such configurations as MoSi, WSi or MoC and WC increase friction resistance of newly developed bronzes, however to lesser extent than it is observed in case of introducing Mo or W. All the examined additions increase/intensify adhesive resistance of new bronzes without oiling. In descending sequence the following configurations of additions influence the increase in adhesive resistance without oiling: first CrSi, MoSi, WSi, CrMoWSi, second Cr, Mo, W, CrMoW, third CrC, MoC, WC, CrMoWC. With the use of oil the examined bronzes were showed comparable adhesive resistance to bronze CuAl10Fe5Ni5-C. The hereby research contributed to elaborate the theory and technological bases for controlling microstructure of bronzes, which help determine the micro-structure resulting from crystallization of intermetallic phases enriched mainly with such elements as Cr, Mo, W, carbides (Cr, Mo, W, C), silicides (Cr, Mo, W, Si), and/or phases or transformations of phases in solid state of aluminum bronzes with such additions as Cr, Mo, W, C as well as Si. The study enables to develop cast high-quality complex aluminum bronzes either in liquid state or after heat treatment having more desired properties. What is more, it can extend the exploitation time of casts made of these bronzes by reducing wear intensity of their structuring elements.

11

Possibilities of obtaining and controlling high-quality pressure castings

Pietrowski S., Walczak W., Pisarek B., Władysiak R.

Archives of Foundry Engineering

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2011

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Vol. 11, iss. 3

125-142

EN

The paper presents the influence of the type of furnace charging melting, refining and modification silumins 226 and 231 on the porosity and microstructure of castings. It was shown that in order to reduce or eliminate the porosity of the castings is necessary to the refining ECOSAL-AL113 of liquid silumin both in the melting furnace, and in the ladle and an additional nitrogen, in the heat furnace modified and refining with nitrogen. To control the effects of refining and modifying the TDA method was used. It was found that based on crystallization curve can be qualitatively assess the gas porosity of the castings. In order to control and quality control silumins author developed a computer program using the method of TDA, which sets out: Rm, A5, HB and casting porosity P and the concentration of hydrogen in them. The program also informs the technological procedures to be performed for liquid silumin improper preparation.

12

Manufacturing technology of high-quality pressure castings

Pietrowski S., Pisarek B., Władysiak R.

Archives of Foundry Engineering

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2011

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Vol. 11, iss. 4

109-122

EN

The paper presents manufacturing technology of pressure castings made of Al-Si alloy without porosity or with low microporosity of castings. It has been shown that the greatest impact on the porosity of the castings and the concentration of hydrogen has had the charge to the melting furnace. Liquidation or occurrence of a small microporosity of castings provides refining with solid ref iners, nitrogen and modification of liquid alloy after various operations of preparing process. The liquid alloy stored in holding furnace should be refined once every 2 h with nitrogen. Authors developed a computer program of Al-Si alloys inspection with using of TDA method. The developed technology was verified under production conditions.

13

Influence of the technology of melting and inoculation preliminary alloy AlBe5 on change of concentration of Al and microstructure of the bronze CuAl10Ni5Fe4

Pisarek B.

Archives of Foundry Engineering

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2010

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Vol. 10, iss. 2

127--134

EN

Examining was the aim of the work: influence of the permanent temperature 1300°C ± 15°C and changing time of isothermal holding in the range 0÷50 minutes on the melting loss of aluminum in the bronze CuAl10Ni5Fe4; the quantity the slag rafining - covering Unitop BA-1 (0÷1,5%) on the effectiveness of the protection of liquid bronze before the oxygenation, the quantity of the preliminary alloy - in-oculant AlBe5 (0÷1,0%) on the effective compensation melting loss of aluminum and time of isothermal holding on the effect of the in-oculation of the bronze and the comparison of the effectiveness of the inoculation of the bronze in furnace and in the form. Introduced investigations resulted from the study of the new grades of the Cu-Al-Fe-Ni bronze with additions singly or simultaneously Si, Cr, Mo and/or W, to melting which necessary it is for high temperature and comparatively long time isothermal holding indispensable to the occur of the process of diffusive dissolving the high-melting of the bronze components. High temperature and lengthening the time of isothermal holding the liquid bronze in casting furnace the melting loss of Al influences the growth. Addition the slag of covering-refining Unitop BA-1 in the quantity 1,5% the bronze protects before the melting loss of aluminum by the time of isothermal holding in the temperature 1300°C about 15 minutes. Addition of the preliminary alloy AlBe5 in the quantity 0,6% it assures the effective compensation of the aluminum which melting loss undergoes for the studied parameters of the melting. The effect of the inoculation of the bronze together with diminishes the preliminary alloy AlBe5 with lengthening the time of isothermal holding. Because of this, use of the method of introducing the preliminary alloy it is seems good solution on the inoculation of aluminum bronzes directly to form, unsensitive on the time of isothermal holding the bronze.

14

The thermal analysis and derivative bronzes cast to plaster moulds

Pisarek B., Pawlak M.

Archives of Foundry Engineering

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2009

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Vol. 9, iss. 3

159-168

EN

It plaster moulds gets casted the alloys of following metals: Al, Cu, Ag, Au in precise and artistic founding. The investigation of the crystallization of bronzes in hot plaster moulds the method of the thermal analysis and derivative (TDA) was not realized out so far. Probe TDAg and tripod enabling the execution of measurements on inductive casting machine INDUTHERM-VC 500D were designed for this technology especially. It was confirmed that one the method TDA can identify the crystallization process of the bronze in hot plaster moulds. The investigations of the superficial distribution of the concentration of elements in the microstructure of the studied grades of the bronze on X-ray microanalizer were conducted. It results that they be subject to in bronze CuSn10-C (B10) and the CuSn5Zn5Pb5-C (B555) of strong microsegregation from conducted investigations: Pb, Sn and Sb. The single separates of intermetallic phase \kappa was identified in the bronze B10 rich first of all in Zn, Sn, Sb and Fe, and two intermetallic phase, one rich were identified in the bronze B555 first of all in Zn, Sb, (Nor, Fe) and second rich in Sn, Sb, (Nor, Fe). The most homogeneous microstructure from the bronze CuAl10Fe5Ni5-C (BA1055) is characterizes among the studied grades of the bronze in the cast state.

15

Selection of the temperature of casting the bronzes to plaster moulds

Pisarek B., Pawlak M.

Archives of Foundry Engineering

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2009

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Vol. 9, iss. 4

203-208

EN

The results of the investigations of the process of solidification of the bronze CuSn5Zn5Pb5-C (B555) and CuSn10-C (B10) in the hot plaster mould show in the work. For four temperatures of casting: 1200 o C, 1180 o C, 1160 o C and 1140 o C was conducted the investi-gation: the size of contraction cavity, the fulfillment of the mould cavity formative the casts of test slats about the thickness: 4 mm, 0,8 mm and 0,5 mm. It was conducted the investigation the processes sets in the arrangement the cast-mould and X-ray analysis phase XRD of compound coming into being in indirect layer created among mould and cast in the result of the thermal decomposition of the anhydrite. It results that the temperature 1140 o C is the optimum temperature of casting the bronze to hot plaster mould from carried out investigations. The minimum thickness of the wall of the cast from the bronze B555 is 0.5 mm, and from the bronze B10 0.8 mm. The realization of casts about thinner walls is made difficult because of giving off formed gases in the result of the thermal decomposition of the anhydrite. The products of the decomposition of the anhydrite react with elements steps in the chemical composition of studied bronzes, create in the arrangement the cast-mould the indirect layer folded from: sulphites, sulphides, oxides and clean metals (Pb) or their compounds, especially Sn and Sb.

16

Computer-aided control of high-quality cast iron

Pietrowski S., Pisarek B., Gumienny G.

Archives of Foundry Engineering

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2008

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Vol. 8, iss. 1

101-108

EN

The study discusses the possibility of control of the high-quality grey cast iron and ductile iron using the author's genuine computer programs. The programs have been developed with the help of algorithms based on statistical relationships that are said to exist between the characteristic parameters of DTA curves and properties, like R_p0,2, R_m, A_5 and HB. It has been proved that the spheroidisation and inoculation treatment of cast iron changes in an important way the characteristic parameters of DTA curves, thus enabling a control of these operations as regards their correctness and effectiveness, along with the related changes in microstructure and mechanical properties of cast iron. Moreover, some examples of statistical relationships existing between the typical properties of ductile iron and its control process were given for cases of the melts consistent and inconsistent with the adopted technology. A test stand for control of the high-quality cast iron and respective melts has been schematically depicted.

17

Characteristic of DTA curves for cast ferrous alloys

Pietrowski S., Pisarek B., Gumienny G.

Archives of Foundry Engineering

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2008

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Vol. 8, iss. 1

183-197

EN

The study presents DTA curves for selected grades of single phases and eutectic were discussed. The thermal effects having their origin in crystallisation of secondary carbides were determined. It has been indicated that the range of temperatures of their crystallisation can be determined from the cooling curve [...]

18

Computer- Aided Technology of Melting High-Quality Metal Alloys

Pietrowski S., Pisarek B.

Archives of Metallurgy and Materials

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2007

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Vol. 52, iss. 3

481-486

EN

The paper describes the potentials of computer-aided melting of high-quality metal alloys. This solution enables effective control of alloy quality during melting and before pouring it into the foundry moulds. It is also possible to manufacture castings free from defects caused by alloys of poor quality and effectively control the mechanical properties, e.g. Rp0,2, Rm,HB, A5 etc. The genuine computer programs have been and are designed using the principles of derivative thermal analysis (DTA). The algorithms used in these programs are based on statistical relationships which are said to exist between the characteristic parameters of DTA curves and the required properties of castings. The study gives examples of DTA curves plotted for AlSi7Ni5Cu4Mg0,5Cr0,5Fe0,5 silumin, for ductile iron with carbides, and for CuAl10Fe5Ni5-C aluminium bronze. Phase crystallisation responsible for the occurrence of thermal effects on the derivative curve has been discussed. Examples of statistical relationships used for determination of Mg content, Rm value and percent content of graphite characterised by the shape factor close to 1 have been given, and procedures used in control of the alloy melting process have been described. It has been proved that control is an indispensable tool in zero-defect manufacture of castings from high-quality alloys.

PL

W pracy przedstawiono możliwości wspomagania komputerowego technologii topienia wysokojakosciowych stopów metali. Umożliwia ono kontrole jakości stopów podczas ich wytapiania, przed odlaniem do form odlewniczych. Zapewnia to otrzymywanie odlewów bez wad spowodowanych niewłaściwą jakością stopów oraz kontrole ich właściwości mechanicznych, np. Rp0,2, Rm, HB, A5 itp. Autorskie programy komputerowe budowane są z wykorzystaniem analizy termicznej i derywacyjnej (ATD). Podstawa budowy algorytmów programów są zależności statystyczne pomiędzy charakterystycznymi wielkościami krzywych ATD, a wymaganymi własnościami odlewów. W pracy przedstawiono przykładowe krzywe ATD dla siluminu AlSi7Ni5Cu4Mg0,5Cr0,5Fe0,5, żeliwa sferoidalnego z węglikami i brązu aluminiowego CuAl10Fe5Ni5-C. Omówiono krystalizację faz powodujacych wystąpienie określonych efektów cieplnych na krzywych derywacyjnych. Przedstawiono przykłady zależności statystycznych dla określenia w żeliwie sferoidalnym stężenia Mg, wartości Rm i udziału procentowego grafitu o współczynniku kształtu zbliżonym do 1. Zamieszczono procedury kontroli procesu topienia stopów. Wykazano, że jest ona niezbędna w bezbrakowej produkcji odlewów ze stopów wysokojakosciowych.

19

Szacowanie kosztów zapewnienia jakości stopów z wykorzystaniem systemu "Arena"

Pisarek B.

Archiwum Odlewnictwa

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2006

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R. 6, nr 19

267-276

PL

W pracy przedstawiono wykorzystanie programu ARENA do symulacji procesu produkcyjnego, przykładowo wytapiania i odlewania staliwa, monitorowanego autorskim programem komputerowym pod względem zgodności z wymaganiami technologicznymi. Na podstawie danych z symulacji określono wartość odpowiednich składników kosztów jakości i kosztów międzywydziałowych związanych z usuwaniem niezgodności z technologią przygotowanego staliwa.

EN

It present use of ARENA for simulation of production system for example of melting and casting of cast steel, in respect of acceptability status monitored technological method of thermal and derivative analysis with author software. Value of component of costs of proper quality define of base from simulation data and with deletion of incompatibility with technology prepared interdepartment costs of cast steel.

20

Monitorowanie produkcji żeliwa sferoidalnego w warunkach odlewni

Pietrowski S., Gumienny G., Pisarek B.

Archiwum Odlewnictwa

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2006

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R. 6, nr 19

239-250

PL

W pracy przedstawiono możliwość i przebieg procesu monitorowania oraz kontroli produkcji żeliwa sferoidalnego w warunkach odlewni przy użyciu autorskiego programu komputerowego wykorzystującego metodę analizy termicznej i derywacyjnej (ATD).

EN

In this paper process of production control of ductile cast iron under foundry conditions with the self-written computer programme using TDA method have been presented.