PL
 |
EN
Preferencje help
Polish version English version Język
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 23

Liczba wyników na stronie
first rewind previous Strona / 2 next fast forward last
Wyniki wyszukiwania
Wyszukiwano:
w słowach kluczowych:  odlewnictwo precyzyjne
help Sortuj według:

help Ogranicz wyniki do:
first rewind previous Strona / 2 next fast forward last
1
Content available Rola odlewnictwa precyzyjnego w inżynierii materiałowej
Wiśniewski Paweł
Szkło i Ceramika
|
2022
|
R. 73, nr 3
30--37
PL
W artykule przedstawiono zagadnienia związane z inżynierią materiałową, ceramiką i odlewnictwem precyzyjnym. Opisano historię i przebieg procesu odlewania detali i części silników lotniczych metodą traconego wosku. Manuskrypt zawiera również generalne informacje o spoiwach, proszkach, masach formierskich, formach odlewniczych i nadstopach niklu. Zaprezentowano podstawowe dane o spoiwach zawierających nanocząstki ceramiczne, modelach woskowych, na które nanoszone są masy lejne oraz o SiC - jednym z perspektywicznych proszków formierskich.
EN
The paper presents the main issues related to materials engineering and technology, ceramics and precision casting process. The history and methodology of the lost-wax casting process of elements and aircraft engine parts is described. The manuscript also contains general information on binders, powders, molding compounds, foundry molds and nickel superalloys. Basic data on binders containing ceramic nanoparticles, wax models and SiC - one of the prospective molding powders are presented.
2
Content available Ocena budowy wielowarstwowych form ceramicznych pod kątem nieciągłości wewnętrznych przy zastosowaniu metody rentgenowskiej tomografii komputerowej
Tchórz Adam, Krzak Izabela, Książek Marzanna
Journal of Applied Materials Engineering
|
2019
|
Vol. 59, no. 3
137--145
PL
W pracy przedstawiono możliwości zastosowania rentgenowskiej tomografii komputerowej (CT) do oceny jakości technologicznej wielowarstwowych form ceramicznych stosowanych w procesie precyzyjnego odlewania. Zaprezentowano koncepcje prowadzenia badań pod kątem ujawnienia i wizualizacji określonych nieciągłości wewnętrznych w strukturze odlewniczych form ceramicznych, a następnie określenia ich charakteru. Rejestracja tomograficzna oparta na analizie obrazów 2D i 3D umożliwiła identyfikację nieciągłości wewnętrznych w formach ceramicznych, pod kątem rozwarstwień czy porowatości wraz z wyznaczeniem jej procentowej ilości, objętości, kształtu porów. Badania wykonano dla dwóch różnych form ceramicznych (molochitowej i kwarcowej), wykonanych metodą wytapianych modeli.
EN
This study presents the possibility of using x-ray computed tomography (CT) for the technological quality assessment of multi-layer ceramic moulds used in the precision casting process. Testing concepts were presented with regard to the detection and visualisation of specific internal discontinuities in the structure of ceramic moulds and the determination of their nature. Tomographic recording based on 2D and 3D images enabled the identification of internal discontinuities in ceramic moulds with regards to delamination or porosity with the determination of the percentage of their count, volume and pore shape. The tests were performed for two different ceramic moulds (molochite and quartz) made with the melted models method.
3
Content available remote Nowoczesne spoiwa ceramiczne w odlewnictwie precyzyjnym
Cygan R.
Szkło i Ceramika
|
2018
|
R. 69, nr 2
25--27
4
Content available Monitoring of Manufacture Stability of Large Turbine Blades Using Infrared Thermography (IRT) in Investment Casting Technology
Herman A., Vrátný O., Kubelková I.
Archives of Foundry Engineering
|
2018
|
Vol. 18, iss. 4
9--14
EN
With increasing technology development, an increasing emphasis is placed on the precision of products, but cannot be guaranteed without a stable production process. To ensure the stability of the production process, it is necessary to monitor it in detail, find its critical locations and eliminate or at least control it. With such a precise manufacturing method as investment casting, such a process is a must. This paper therefore deals with monitoring the production process of wax models of large turbine blades using infrared thermography. The aim was to evaluate the critical locations of this production and to propose recommendations for their elimination or, at the very least, significant mitigation of their impact on the final quality of the large turbine blade casting.
5
Content available Comparison of Dental Prostheses Cast and Sintered by SLM from Co-Cr-Mo-W Alloy
Myszka D., Skrodzki M.
Archives of Foundry Engineering
|
2016
|
Vol. 16, iss. 4
201--207
EN
The article presents the results of a comparative analysis of the metal substructure for dental prosthesis made from a Co-Cr-Mo-W alloy by two techniques, i.e. precision investment casting and selective laser melting (SLM). It was found that the roughness of the raw surface of the SLM sinter is higher than the roughness of the cast surface, which is compensated by the process of blast cleaning during metal preparation for the application of a layer of porcelain. Castings have a dendritic structure, while SLM sinters are characterized by a compact, fine-grain microstructure of the hardness higher by about 100 HV units. High performance and high costs of implementation the SLM technology are the cause to use it for the purpose of many dental manufacturers under outsourcing rules. The result is a reduction in manufacturing costs of the product associated with dental work time necessary to scan, designing and treatment of sinter compared with the time needed to develop a substructure in wax, absorption in the refractory mass, casting, sand blasting and finishing. As a result of market competition and low cost of materials, sinter costs decrease which brings the total costs related to the construction unit making using the traditional method of casting, at far less commitment of time and greater predictability and consistent sinter quality.
6
Content available Zastosowanie tlenku itru do budowy warstwy przymodelowej ceramicznych form odlewniczych stosowanych w odlewnictwie precyzyjnym
Małek M., Wiśniewski P., Matysiak H., Nawrocki J., Kurzydłowski K. J.
Szkło i Ceramika
|
2013
|
R. 64, nr 6
8--11
PL
W artykule przedstawiono wyniki badań ceramicznej masy lejnej o stężeniu fazy stałej 81% wag. na osnowie proszku tlenku itru o dwóch granulacjach 200 mesh i 325 mesh dodanych w proporcji 35%-65% wagowych. Y2O3 jest nowym materiałem do budowy warstwy przymodelowej ceramicznej formy odlewniczej stosowanej w procesie odlewania precyzyjnego części turbin lotniczych ze stopów niklu i tytanu o dużych reaktywnościach. Oceniano właściwości reologiczne i fizykochemiczne ceramicznej masy odlewniczej, w której spoiwem wzmacniającym był nanokompozyt zawierający koloidalny tlenek glinu, natomiast jako spoiwa modyfikującego użyto dyspersji poli(akrylowej) w ilości 15% wag. w stosunku do proszku. Przeprowadzono badanie wielkości cząstek stosowanych proszków oraz obserwacje ich mikrostruktury. Dodatkowo zostały wykonane badania reologiczne ceramicznej masy odlewniczej, tj. lepkość względna i dynamiczna, wartość pH, gęstość oraz zanurzeniowy test płyty mosiężnej. Pomiary przeprowadzano przez 96 h w warunkach laboratoryjnych w temperaturze 21°C. Po przeprowadzonych badaniach i stwierdzeniu przydatności masy ceramicznej do procesów odlewniczych z powodzeniem wytworzono formy ceramiczne do odlewania łopatek turbin lotniczych techniką Bridgmana.
EN
This work present the rheological properties of ceramic slurries based on yttrium oxide powders with two different granulation (200 mesh and 325 mesh) added in a ratio of 35%-65% by weight. Solid phase was 81 wt.%. To manufacture ceramic shell moulds the Evonik binder with nanoparticles of aluminium oxide was used. In addition the poli(acrylic) binder as a liquefier was also used. Y2O3 it's a new material used to fabricate ceramic shell moulds for investment casting of turbine aircraft parts using nickel and titanium superalloys. Grain size and microstructure observation were researched for yttria. Relative and dynamic viscosities, density, pH and plate weight test of ceramic slurries were studied. The measurements were taken by 96 hours. It were proven that ceramic slurries based on yttrium (III) oxide meet the standard investment casting requirements. After tests, ceramic shell moulds for investment casting aircraft turbine parts were manufactured by Bridgman technique.
7
Content available Nakładanie warstw niklowych na modele do odlewania precyzyjnego
Jesiotr M., Tarnowski M., Kucharska B., Myszka D., Wierzchoń T.
Prace Instytutu Odlewnictwa
|
2013
|
T. 53, z. 3
45--51
PL
W artykule przedstawiono sposób modyfikacji powierzchni form ceramicznych na granicy rozdziału model wytapiany - ceramika poprzez zastosowanie warstwy niklowej na jednorazowym modelu wykonanym z określonego rodzaju polimeru, np. polimetakrylanu metylu (PMMA), a następnie nałożenie na tak przygotowany model warstw formy ceramicznej. Kolejne fazy zakładają usunięcie modelu ze skorupy ceramicznej, tak aby metaliczna warstwa pozostała wewnątrz formy. Do przygotowanej w ten sposób formy, po procesie wyżarzania, możliwe będzie wlanie ciekłego metalu o określonej temperaturze topnienia, np. stopu aluminium. W ten sposób można będzie uzyskać wysokiej jakości powierzchnię odlewu, o określonej chropowatości i braku wad powierzchniowych. Hipotezą badawczą postawioną w artykule jest takie zaprojektowanie metalicznej powłoki w formie ceramicznej, aby uzyskać jej lepszą zwilżalność ciekłym metalem niż przy zastosowaniu konwencjonalnych technik odlewania precyzyjnego.
EN
The article presents a method of modification of ceramic mould surface on the boundary between lost-wax model - ceramics by using a layer of nickel on a disposable model made of a specified type of polymer e.g. polymethyl methacrylate (PMMA) and then applying the layers of a ceramic mould to such a model. Successive phases consist in removing the model from the ceramic shell so that the metallic layer remains in the mould. After annealing it will be possible to pour liquid metal of a specific melting point e.g. aluminium alloy, to a mould prepared in this way. This way it is possible to obtain a high quality casting surface, of certain roughness and lack of surface defects. The research hypothesis stated in the article is to design a metallic coating in a ceramic form to get better wettability with molten metal than when using conventional techniques of precision casting.
8
Porowatość i wytrzymałość form ceramicznych wykorzystywanych w procesie odlewania precyzyjnego metodą Bridgmana
Matysiak H., Ferenc J., Michalski J., Lipiński Z., Jakubowicz G., Kurzydłowski K. J.
Inżynieria Materiałowa
|
2011
|
Vol. 32, nr 1
17-21
PL
Praca dotyczy badań właściwości wytrzymałościowych i porowatości dwóch rodzajów form ceramicznych stosowanych w procesie odlewania precyzyjnego łopatek turbin silników odlewniczych metodą Bridgmana (opartych na tlenku glinu i mulicie). Wyznaczono objętość względną porów, %, rozkład wielkości porów i średnią średnicę porów, ?m, gęstość materiału formy, g/cm3, wytrzymałość na zginanie, MPa, oraz moduł Younga, MPa, i moduł Weibulla. Badaniom poddano formy ceramiczne w trzech stanach: po usunięciu wosku (w stanie "surowym", T = 25°C) oraz po obróbce cieplnej w temperaturze 700°C i 1500°C.
EN
The study of porosity and strength of two types of ceramic shells: (a) based on alumina and (b) on mullit was carried out. Weibull distribution was used to describe the statistical strength of the ceramic shells for Bridgman investment casting process. The porosity and average pore diameter were measured. Shells were tested: at green state, after burn-out at 700°C and after firing at 1500°C. It has been found that data obtained from the porosity examinations are in good agreement with strength results (average bending strength and Young modulus).
9
Content available Temperature and microstructure characteristics of silumin casting AlSi9 made with investment casting method
Pietrowski S., Rapiejko C.
Archives of Foundry Engineering
|
2011
|
Vol. 11, iss. 3 spec.
177--186
EN
This work presents the research result of the temperature distribution and the microstructure in certain parts of the field-glass body frame casting made from silumin AlSi9 using the investment casting method in the ceramic mould. It was proved that the highest temperature of the silumin appears in the sprue in which the silumin is in the liquid-solid state, though the process of silumin crystallization in the casting is finished. It was stated that in certain elements of the casting the side opposite to the runner crystallizes and cools fastest. The differences in the rate of crystalline growth and cooling of certain casting elements cause different microstructure in them which can also influence the mechanic properties. It is necessary to state that the temperature of the initial heating of the ceramic mold equal to 60ºC guarantees obtaining of the castings without defects and of little porosity. Incomplete modification of the silumin with strontium causes silica precipitation to appear close to the spherical ones.
10
Content available remote The influence of the conditions of gypsum plaster preparation on its technological properties
Pawlak M.
Archives of Foundry Engineering
|
2010
|
Vol. 10, iss. 2
95--98
EN
The results of researches on influence of basic preparation parameters, i.e. time and mixing intensity, start and end time of set, dimensional changes and strength of gypsum plaster, are presented in this paper. Determination of mentioned above parameters has a significant meaning because of their influence on quality of gypsum plaster and its susceptibility to even small disturbances during preparation. Tested plaster was prepared in vacuum mixer St. LOUIS 82. Time of mixing was 60÷360 sec., mixer arm rates 150÷420 rpm. It was demonstrated that mixing time influences strongly the setting time and expansion of gypsum plaster , and this influence growths with growing mixing intensity. The intense, short time mixing is beneficial from the viewpoint of dimensional changes minimizing. Minimizing the setting time is the most beneficial at low mixing intensity but significant dimensional changes appear during setting the plaster.
11
Content available remote Computer aided process of dimensional distortion determination of bounded plaster sandmix Part II
Pawlak M., Niedźwiedzki Z.
Archives of Foundry Engineering
|
2010
|
Vol. 10, iss. 1
105-108
EN
A computer program allowing calculation of dimensional changes of mould made of cristobalite-gypsum composition in process of its heat treatment and preparation for molten metal casting is presented in this paper. The composition of the mixture and casting temperature to obtain cast of predetermined dimensions can be calculated using presented software. The base for program elaboration were the results of dilatometric test of bounded plaster sandmix composed of half hydrate [alpha]-CaSO_4 x 0,5H_2O of various cristobalite ratio. Approximation was carried out in the range of temperatures 100 - 700°C.
12
Content available remote Ability of the CuSn10 and CuSn5Zn5Pb5 brasses fulfillment of plaster mould cavity during underpressure casting
Pawlak M.
Archives of Foundry Engineering
|
2010
|
Vol. 10, iss. 4
163--168
EN
Results of research on ability of a plaster mould cavity to be filled up on casting with alloy CuSn10 and CuSn5Zn5Pb5 are presented in this paper. The cylindrical plaster mould ø110x290 was casting using underpressure in the Vacuum Pressure Casting Machine VC500D of Indutherm. The size of mould cavity was ø15x200 mm and gauge: 2,0; 1,0; 0,8 and 0,6 mm, the temperature of pouring alloy was 1120, 1140, 1160, 1180 and 1200°C, temperature of plaster mould in the casting moment was 400, 500 and 600°C. The effectiveness of a mould cavity to be filled up on the difference distance from the centre of the mould was assesmented too used to mould cavity 10x200 mm and gauge: 2,0; 1,0; 0,8 and 0,6 mm. On the base of the results of the investigation its possible to reach a conclusion, that the best temperature of casting and temperature of the plaster mould tf=500÷600°C. The distance of mould cavity from the mould centre doesn’t have a practical meaning for its ability to be filled up.
13
Content available remote Quality problems root cause identification and variability reduction in casting processes
Furgał G., Cygan R.
Archives of Foundry Engineering
|
2009
|
Vol. 9, iss. 1
13-16
EN
Increasing customer requirements and production costs force casting manufacturers to adopt a methodological approach to manufacturing processes, in order to deliver increasingly more repeatable, predictable and competitive products. One of the methods of achieving such results is the reduction of variability of manufacturing processes and the optimization of their control. This paper presents the possibilities granted by the Six Sigma methodology in efficient identification of special factors influencing pre-heat of ceramic moulds and casting parameters, in the minimization of the frequency at which they occur, and in the reduction of key process parameters variability. This paper also shows the usability of the method in achieving measurable business advantages for the company using the example of one DMAIC methodology based project realized in the Investment Foundry Department of WSK 'PZL-Rzeszow' S.A.
14
Content available remote Permeability of mould made by lost wax casting process
Sarek D., Trytek A., Nawrocki J.
Archives of Foundry Engineering
|
2009
|
Vol. 9, iss. 1
203-206
EN
Paper present results of permeability of moulds which have been made by lost casting wax process. Measurement and tests have been made using typical sand cast permeability tester. Measurement technique required preparing of special shape samples. All scope of tests have been realized in WSK 'PZL-Rzeszów' S.A. Results showing permeability of ceramic moulds in function of quantity layers.
15
Content available remote Investment casting or powder metallurgy - the ecological aspect
Tomasik J., Haratym R., Biernacki R.
Archives of Foundry Engineering
|
2009
|
Vol. 9, iss. 2
165-168
EN
The paper presents an analysis of manufacturing methods of material-saving products in relation to investment castings and sintered powder technology. Surface microgeometry, shape accuracy, performance parameters, manufacturing costs and energy consumption were taken into account to make the optimal choice. The analysis was conducted by comparing test results for sintered powder products based on Distaloy AB alloy that consists of 0.55% C, 1.5% Cu, 1.75% Ni and 0.5% Mo and investment castings made of high alloy cast steel and nodular cast iron. The analysis made it possible to choose the best technology, considering also the ecological aspect.
16
Content available remote The influence of organic fibre types on technological parameters in process of ceramic moulds making
Karwiński A., Młodnicki S., Meksa W., Woźnicki G.
Archives of Foundry Engineering
|
2007
|
Vol. 7, iss. 2
143-146
EN
The research being presented in this article has been set up with the aim of working out both the technology and starting up manufacturing process ( in which a new generation of ceramic slips is employed ) in "Armatura" precise foundry. There have been used "aqueous" Ekosil silicate binder and quartz ceramic material with addition of organic fibres for making slip in the new technological solution. In the presented research work has been achieved a quantitative and qualitative selection of composition for the ceramic slip. The selection has been based on testing of physico-chemical and technological qualities.
17
Content available remote Investigation of field temperature in moulds of foamed plaster
Pawlak M., Niedźwiedzki Z.
Archives of Foundry Engineering
|
2007
|
Vol. 7, iss. 4
141-146
EN
Plaster moulds used in precision foundry are characterized by a very low permeability which, in the case of classic plaster moulds, equals to about 0,01- 0,02 m2/(MPaxEs). One of the most effective methods for increasing the permeability is a foaming treatment. Another characteristic feature of plaster is its very good insulating power which has influence on the process of solidification and cooling of a cast and also on a knock-out property. This insulating power is a function of thermophysical properties of plaster which, in turn, depend mainly on the mineralogical composition of the mould material, its bulk density as well as on the temperature of the pouring alloy. In the case of a foamed plaster mould an increase of the degree of foaming increases its porosity which causes a change in its thermophysical properties, thereby increasing susceptibility of the mass to overheating. The susceptibility of the plaster layer surrounding the cast to overheating is favorable because it makes it easier to knock-out of the cast by immersing the hot mould in cold water. Thermal and phase tensions that are created during this process cause fast destruction of plaster. This paper describes our investigations aimed at the determination of the dependence of the mould temperature field on the time of the cast stay in the mould, as recorded in a process of an unsteady heat flow. The determined data were planned to be used for estimation of the technological properties of the plaster mould. The tests were carried out using the plaster [alpha]-Supraduro and Alkanol XC (foaming agent). The test mould had a diameter of [...] 120 mm with centrally situated mould cavity of [...] 30 mm. Plaster moulds with a degree of foaming 20; 32,5 and 45% and comparatively from non-foaming plaster were tested and their temperatures were measured at the distance x=2; 9; 21; 25; 27; 30 mm from the mould cavity within 25 min. Analysis of the results leads to the conclusion, that the highest effectiveness of heating and overheating of a mould made of a foamed plaster occurs at the degree of the plaster foaming equal to S_S=45%. The results obtained can provide the basis for the elaboration of the best plaster mould properties, and thus to increase the technology effectiveness.
18
Content available remote Influence of conditions of preparing the foamed plaster on its degree of foaming
Pawlak M.
Archives of Foundry Engineering
|
2007
|
Vol. 7, iss. 3
105-110
EN
Foamed plaster moulds are used in precision casting process of non-ferrous alloys. Casting from those moulds are characterizedby high dimensional accuracy, very good shape pattering and small surface roughness. However, a drawback of the plaster mould is very low permeability. A substational improvement of this parametr may be achived through physical or phisico-chemical treatment of the plaster slurry or prepared mould. The most advantageous results can be obtained by foaming the slurry. The investigatious comprised evaluation of the influence of mixing parametrs (mixer type, rotation and mixing time, settings the mixer in mixing device) and the content of a foaming agent on the degree of foaming of the plaster. The tests were carried out using the [alpha]-plaster Hartform-H1 and Alkanol XC as a foaming agent. The structure of a slurry produced after foaming is non-homogeous. Therefore, the investigations were completed by making appropriate of this process. Analysis of the results leads to the conclusion, that the foamed plaster Hartform-H1 reaches the top degree of foaming at the following parameters: the water/plaster ratio W/G=0.55, the content of Alkanol XC a=0.07%, stirring with a perforate disc mixer at the rotation speed nm=4000 rpm during ôm=30 s. In turn the top homogeneity of the foamed plaster slurry can be achieved at the rotation speed nu=1400 rpm during ôu=30 s., while other parameters are the same as in the foaming process. The obtained results can provide the basis for the elaboration of the industry procedures useful in the production of the plaster moulds for precision casting.
19
Content available remote Wpływ składu masy gipsowej na termiczne zmiany wymiarowe formy stosowanej w odlewnictwie precyzyjnym
Wiktorski M., Pawlak M., Niedźwiedzki Z.
Archiwum Odlewnictwa
|
2005
|
R. 5, nr 17
365--374
PL
W pracy przedstawiono wyniki badań dylatometrycznych związanych mas gipsowych o różnym udziale tlenku glinu, węglika krzemu, krzemionki oraz talku. Omówiono rolę, jaką spełniają kompozycje dodatków stosowanych jako materiał na formy w odlewnictwie precyzyjnym.
EN
In this work dilatation of set gypsum mix with alumina, silicon carbide, silica and talc are presented. The influence of the additives on the properties of material used for moulds in precision casting are disciussed.
20
Content available remote Stanowisko do badania współczynnika przewodzenia ciepła materiałów stosowanych na formy gipsowe w odlewnictwie precyzyjnym
Wiktorski M., Pawlak M., Niedźwiedzki Z.
Archiwum Odlewnictwa
|
2004
|
R. 4, nr 13
233--240
PL
W pracy przedstawiono stanowisko do wyznaczania współczynnika przewodzenia ciepła oraz omówiono metodę jego obliczania.
EN
The stand for thermal conductivity coefficient determination as well as its calculation method have been presented. Results of plaster moulding composition for precision casting have been published. The stand reproduces casting mould under real conditions well. Moreover, it can be used for all types of moulding sands.
first rewind previous Strona / 2 next fast forward last
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.