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1

New method for assessing discontinuities of the surface layer based on the surface roughness measurements

Łętocha A., Putyra P., Podsiadło M., Momot K., Klimczyk P., Toboła D., Jaworska L.

Journal of Achievements in Materials and Manufacturing Engineering

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2024

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Vol. 124, nr 1

17--24

EN

Purpose: There are several methods for examining open porosity: Archimedes, image analysis, porosimetry and computed tomography. The research aimed to develop a new and quick method for determining discontinuities of the surface layer using surface texture measurements. Design/methodology/approach: Investigations were carried out in two stages. The first one, an areal roughness measurement standard, was used. The second one included testing metallic samples prepared by Selective Laser Sintering (SLS). The surface roughness of all samples was determined using the optical confocal profiling method. The Archimedes and image analysis (grid method) were used to analyse open porosity. Selected roughness parameters related to the volume and depth of the dales were calculated. Findings: A new method for testing discontinuities of the surface layer based on surface texture measurements was developed. The new method enables quick analysis of the surface layer of samples obtained by 3D sintering. It can be successfully used alone or as an additional source of information about the tested sample during roughness measurements. The obtained results regarding discontinuities of the surface layer are strongly related to the open porosity of the sample and consistent with those achieved using the Archimedes and image analysis selected as reference methods. Research limitations/implications: The proposed method, presented in the article, concerns testing materials with relatively high porosity. Verifying the method using other materials or different manufacturing techniques will constitute a further research challenge. Practical implications: The main advantage of the proposed method is the shortening of the analysis time of samples. Results from a single device (profilometer) provide information on the surface roughness and discontinuities of the surface layer of the sample. Originality/value: The paper presents a new method for measuring discontinuities of the surface layer related to open porosity. The subject matter should interest researchers involved in the analysis of mechanical and functional properties and surface texture analysis.

2

Właściwości mechaniczne kompozytów narzędziowych z tlenku glinu, wzmacnianych węglikoazotkiem tytanu

Szutkowska M., Boniecki M., Podsiadło M., Kalinka A.

Mechanik

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2018

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R. 91, nr 5-6

438--442

PL

Przedstawiono właściwości mechaniczne kompozytów na osnowie z tlenku glinu, wzmacnianych Ti(C,N) w ilości 30% masy, wytworzonych na bazie proszków komercyjnych, o mikrometrycznych i nanometrycznych rozmiarach cząstek. Zastosowano bezciśnieniowe spiekanie PS w próżni i spiekanie reakcyjne SPS. Wykonano pomiary: twardości Vickersa, gęstości, modułu Younga i odporności na ścieranie. Odporność na pękanie (KIC) wyznaczono w temperaturze pokojowej i podwyższonej do 1073 K – charakterystycznej dla pracy narzędzia. Właściwości fizyczne i mechaniczne kompozytów Al2O3/Ti(C,N)/ZrO2, wytworzonych na bazie mikroproszków, porównano z właściwościami kompozytów zawierających proszki mieszane, mikrometryczne i nanometryczne, z udziałem proszków nanometrycznych od 17% do 36% masy. Kompozyty Al2O3/Ti(C,N)/ZrO2 z udziałem proszków nanometrycznych wykazują w temperaturze otoczenia niższe wartości KIC (o ok. 10÷30%) w porównaniu z kompozytami wytworzonymi na bazie proszków mikrometrycznych. Natomiast w temperaturze podwyższonej do 1073 K ich odporność na pękanie wzrasta nawet o 30%. Obserwacje mikrostruktury badanych kompozytów przeprowadzono za pomocą skaningowej mikroskopii elektronowej.

EN

The present study reports mechanical properties obtained by reinforcing alumina composites with Ti(C,N) in amount 30 wt.% prepared on the basis micro and nanoscale trade powders. The pressureless sintering PS in a vacuum and SPS method of sintering were used. Vickers hardness, density, Young modulus, wear resistance were evaluated. Fracture toughness (KIC) at ambient and elevated temperatures up to 1073 K, characteristic for tool work was measured. Physical and mechanical properties of the composites Al2O3/Ti(C,N)/ZrO2 based on the powders in microscale were compared with composites containing nanoscale powders in a range from 17 to 36 wt.%. Tested composites with nanoscale powders content reveal lower KIC (approx. 10÷30%) at ambient temperature in comparison to composites based on powders in microscale. However, in the elevated temperatures their fracture toughness increases up to 30%. The observation of the microstructure of tested composites was carried out using scanning electron microscopy.

3

Selected properties of ZrB₂ composites obtained by SPS method for parts of electro-erosion shaping machines

Naughton-Duszova A., Bączek B., Podsiadło M.

Mechanik

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2018

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R. 91, nr 2

155--158

PL

Badano wpływ dodatku proszków węglika krzemu i węglika boru na właściwości kompozytów ceramicznych na bazie ZrB2, stanowiących materiały UHTC (ultra high temperature ceramics). Próbki z polikrystalicznego dwuborku cyrkonu oraz kompozyty na osnowie z tej fazy z dodatkiem 2 i 10% wag. SiC oraz B4C otrzymano na drodze spiekania wspomaganego ciśnieniowo, z użyciem metody SPS/FAST (spark plasma sintering/field assisted sintering technique) w temperaturze w zakresie 1800÷2000°C. Otrzymane kompozyty scharakteryzowano pod kątem składu fazowego, mikrostruktury, właściwości mechanicznych i odporności na pękanie. Materiały cechują się wysoką gęstością względną – w zakresie 97÷98%. Wykazano wyższą twardość oraz odporność na pękanie kompozytów o osnowie z dwuborku cyrkonu z dodatkiem faz ceramicznych, otrzymanych w temperaturze 1900°C.

EN

The effect of the addition of silicon carbide and boron carbide powders on the properties of ZrB2 ceramic composites constituting UHTC materials (ultra high temperature ceramics) was investigated. Polycrystalline zirconium boride samples as well as matrix composites of this phase with addition of 2 and 10 wt.% SiC and B4C were obtained by pressure-assisted sintering using SPS/FAST (spark plasma sintering/field assisted sintering technique) in the temperature range of 1800÷2000°C. Samples were characterized by X-ray diffraction, scanning electron microscopy, hardness and fracture toughness. The obtained materials are characterized by a high relative density in the range of 97÷98%. Higher hardness and fracture toughness were observed for the composite obtained in temperature 1900°C.

4

Ocena odporności na pękanie kompozytów UHTC na bazie ZrB2 otrzymanych metodą SPS oraz HP–HT

Bączek E., Naughton-Duszova A., Podsiadło M., Dubiel A.

Materiały Ceramiczne

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2018

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T. 70, nr 1

20--28

PL

W pracy badano wpływ dodatku proszków węglika krzemu i węglika boru na właściwości kompozytów ceramicznych na bazie ZrB2, stanowiących materiały UHTC (ang. ultra high temperature ceramics). Próbki z polikrystalicznego dwuborku cyrkonu, jak również kompozyty na osnowie tej fazy z dodatkiem 2% i 10% wag. SiC oraz B4C, otrzymano na drodze spiekania wspomaganego ciśnieniowo przy użyciu metody SPS/FAST (ang. spark plasma sintering / field assisted sintering technique) oraz HP–HT (ang. high pressure - high temperature). Otrzymane kompozyty scharakteryzowano pod kątem składu fazowego, mikrostruktury, właściwości mechanicznych i odporności na pękanie. Uzyskane materiały charakteryzują się wysoką gęstością względną w zakresie od 97% do 98%. Wykazano wyższą twardość oraz odporność na pękanie dla kompozytów o osnowie dwuborku cyrkonu z dodatkiem faz ceramicznych otrzymanych metodą HP–HT.

EN

The effect of the addition of silicon carbide and boron carbide powders on the properties of ZrB2 ceramic composites constituting ultra high temperature ceramics (UHTC) was investigated. Polycrystalline zirconium boride samples, as well as composites with the matrix of this phase with the addition of 2 wt.% and 10 wt.% of SiC and B4C were obtained by pressure-assisted sintering using SPS/FAST (spark plasma sintering / field assisted sintering technology) and HP–HT (high pressure -high temperature) methods. The composites were characterized in terms of phase composition, microstructure, hardness and fracture toughness. It has been stated that they had a high relative density in the range of 97% to 98%. Higher hardness and fracture toughness was observed for composites with the addition of ceramic phase obtained by HP–HT method.

5

Kształtowanie siluminów z dodatkiem fazy węglikowej – analiza temperatury narzędzi podczas skrawania

Putyra P., Jaworska L., Dyzia M., Podsiadło M.

Mechanik

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2017

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R. 90, nr 2

128--132

PL

Określono trwałość narzędzi z PCD w procesie obróbki skrawaniem odlewanych materiałów kompozytowych z zawartością fazy ceramicznej. Próby skrawania przeprowadzono narzędziami z polikrystalicznego diamentu z wykorzystaniem centrum tokarsko-frezarskiego Mori Seiki NL2000SY. Sprawdzano charakter zużycia VBB zgodnie z normą PN-ISO 3685:1996. Ustalono wpływ parametrów skrawania (prędkości obrotowej, posuwu, głębokości skrawania) na temperaturę ostrzy z PCD. Przeanalizowano mechanizm kształtowania wióra w trakcie obróbki z różnymi parametrami skrawania. Badania zrealizowano z zastosowaniem kamery termowizyjnej FLIR A655 oraz szybkiej kamery Phantom MIRO M310.

EN

The stability of PCD inserts in the machining of cast composite materials containing 10 vol.% of ceramic phase is presented. Tests were carried out using a polycrystalline diamond cutting tool and the turning and milling center Mori Seiki NL2000SY. The VBB wear parameters of inserts according to the standard PN-ISO 3685:1996 were determinated. The influence of the cutting parameters (speed, feed rate, depth of the cut) on the temperature of PCD inserts was investigated. The analysis of chip formation mechanism during the processing at different cutting parameters was performed. The study was carried out using the FLIR A655 thermal camera and the high speed camera Phantom MIRO M310.

6

Badania odporności na zużycie ścierne segmentów metaliczno-diamentowych otrzymanych metodą SPS

Bączek E., Putyra P., Podsiadło M., Staniewicz-Brudnik B.

Mechanik

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2017

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R. 90, nr 8-9

793--795

PL

Przedstawiono wyniki badań właściwości tribologicznych materiałów narzędziowych w procesie szlifowania materiałów kamieniarskich. Otrzymane spieki metaliczno-diamentowe homogenizowano w Speed-Mixerze i spiekano metodą SPS (spark plasma sintering). Materiał osnowy stanowiły proszki: brąz cynowy Cu-Sn (NAM-40 80/20 z zawartością 20% mas. Sn) oraz proszek żelaza z dodatkiem 20% mas. brązu Cu-Sn. Otrzymane materiały poddano badaniom: gęstości pozornej metodą hydrostatyczną, twardości sposobem Rockwella z wykorzystaniem skali B oraz odporności na zużycie ścierne.

EN

This paper presents the tribological properties of the diamond-impregnated specimens in the grinding process of sandstone materials. Obtained metallic-diamond composites were homogenized in Speed Mixer and sintered by SPS (spark plasma sintering). The matrix was prepared from: Cu-Sn (NAM-40 80/20 containing 20% wt. Sn) and Fe-Cu-Sn powders. After consolidation the diamond-impregnated specimens were tested for density using the hydrostatic method, Rockwell’s hardness using B scale and for wear rate on abrasive sandstone using a testing rig specially designed to simulate the tool application conditions.

7

Metody kształtowania materiałów ceramicznych

Putyra P., Podsiadło M., Łaszkiewicz-Łukasik J., Krzywda T.

Mechanik

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2015

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R. 88, nr 2

120--122

PL

Przedstawiono wyniki badania właściwości fizycznych i mechanicznych ceramiki o osnowie z Al2O3, SiC, Si3N4 z dodatkami faz o dobrej przewodności elektrycznej oraz ceramiki o osnowie z TiB2. Określono gęstość, moduł Younga, twardość HV1 oraz przewodność elektryczną poszczególnych materiałów. Ceramiczne materiały kompozytowe z fazami przewodzącymi zostały wytworzone z zastosowaniem urządzenia do spiekania metodą SPS (Spark Plasma Sintering). Materiały odznaczające się dobrą przewodnością elektryczną kształtowano za pomocą obróbki elektroerozyjnej (EDM – Electro Discharge Machining). Powierzchnie materiałów po cięciu elektroerozyjnym poddano analizie z wykorzystaniem skaningowej mikroskopii elektronowej.

EN

Presented in the paper are physical and mechanical properties of the Al2O3, SiC and Si3N4 matrix ceramics with good electrical conductivity phases added and of TiB2 matrix ceramics. Density, elastic modulus, hardness HV1 and electrical conductivity of each material were determined. Ceramic composite materials with conductive phases have been produced using SPS (Spark Plasma Sintering) method. Materials showing good electrical conductivity were shaped by means of EDM (Electro Discharge Machining) method. Material surfaces as left after EDM cutting were inspected by means of scanning electron microscopy.

8

Krystalografia wysokich ciśnień, czyli jak zobaczyć strukturę materii…głębiej

Olejniczak A., Dziubek K., Paliwoda D., Zieliński W., Podsiadło M., Katrusiak A.

Wiadomości Chemiczne

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2014

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[Z] 68, 5-6

487--505

EN

During recent decades the number of high-pressure crystallographic studies has rapidly increased. This has been possible owing to the diamond-anvil cell, a small, relatively cheap and save apparatus breaking all records of static pressure. The diamond-anvil cell is suitable for diffraction structural studies, optical and IR spectroscopy and many other types of physical measurements; it can be also applied as a microscopic chemical reaction chamber. High pressure is now often used for synthesizing super-hard materials, new polymorphs and solvates with unique properties required in high-tech applications as well as in food processing and pharmaceutical industry.

9

Synteza i spiekanie dwuborku tantalu metodą SPS

Laszkiewicz-Łukasik J., Putyra P., Jaworska L., Podsiadło M.

Materiały Ceramiczne

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2014

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T. 66, nr 4

440--445

PL

Materiały ceramiczne o osnowie borków, węglików i azotków metali przejściowych charakteryzują się silnymi wiązaniami kowalencyjnymi oraz wysoką temperaturą topnienia (powyżej 3000 °C). Ceramikę tę charakteryzuje stabilność właściwości fizyko-mechanicznych w szerokim zakresie temperatur, dlatego materiały te mogą znaleźć zastosowanie m.in. na odpowiedzialne komponenty ochrony termicznej, części maszyn pracujące w wysokich temperaturach oraz inne, od których wymagana jest także odporność na utlenianie. W artykule omówiono metodę spiekania reakcyjnego materiałów o osnowie dwuborku tantalu TaB2. Syntezę proszków tantalu i boru oraz proces spiekania przeprowadzono w jednym etapie technologicznym przy zastosowaniu metody SPS/FAST (ang. spark plasma sintering, field assisted sintering technology). Procesy spiekania przeprowadzono w temperaturze 2200 °C. Czas spiekania wynosił 5 min. Prędkość nagrzewania mieściła się w zakresie od 50 °C/min do 400 °C/min. Badania miały na celu określenie wpływu szybkości nagrzewania na mikrostrukturę i właściwości otrzymanych spieków. W pracy zaprezentowano wyniki analiz składu fazowego i mikrostruktury otrzymanych próbek, które przeprowadzono odpowiednio metodą dyfrakcyjną i skaningowej mikroskopii elektronowej (SEM). Dla pełnej charakterystyki materiałów wykonano również pomiary gęstości metodą hydrostatyczną, modułu Younga metodą ultradźwiękową oraz twardości metodą Vickersa.

EN

Ceramic materials composed of a matrix based on borides, carbides and nitrides of transition metals have strong covalent bonds and high melting points over 3000°C. These materials show stability of physical and mechanical properties over a wide temperature range, and therefore can be used as responsible components of thermal protections, machine parts working at high temperatures or other elements for applications which require a resistance to oxidation. This paper presents reactive sintering as a method of the obtaining tantalum diboride TaB2. The synthesis of tantalum and boron powders and the sintering process were carried out in a single technological stage using the SPS/FAST method (Spark Plasma Sintering, Field Assisted Sintering Technology). Sintering processes were carried out for 5 min at a temperature of 2200 °C. Heating rates ranged from 50 °C/min to 400 °C/min. The study aimed to determine the influence of heating rate on the microstructure and properties of the sintered materials. The results of X-ray phase composition and SEM analyses are presented. The density by hydrostatic method, Young's modulus by ultrasonic method, and hardness by Vickers’ indentation were also determined for a complete characterization of the materials.

10

Wykonanie płytek skrawających z monolitycznego spieku diamentowego

Jaworska L, Rozmus M, Laszkiewicz-Łukasik J, Wyżga P, Podsiadło M, Czechowski K

Mechanik

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2012

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R. 85, nr 8-9CD (SOS)

39--46

11

Alumina composites with solid lubricant participations, sintered by SPS-method

Putyra P., Figiel P., Podsiadło M., Klimczyk P.

Kompozyty

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2011

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R. 11, nr 2

107-110

EN

The paper presents the sintering results of Al2O3-Ti(C,N) ceramics with the additions of solid lubricant materials. Al2O3-Ti(C,N) based ceramics with solid lubricating substances were sintered by the SPS-method. In the phase known as lubricants, the following materials were used: MoS2, WS2, CaSO4, SrSO4 and MoO3 and CaO. The Al2O3-Ti(C,N) ceramics were also prepared with the addition of TiB2. The SPS-sintered materials were characterized by values of relative density from 93 to 99%. In the case of the addition of 10 and 30% TiB2, the relative density, Young's modulus and hardness HV1 were close or equal to the values of the base material. For other additions, the Young's modulus ranged from 74 to 83% and hardness from 62 to 76% of the Young's modulus and hardness value for the base material. Regardless of the additive or its volume, the fraction of the friction coefficient was 49 to 86% of the friction coefficient value for the base material. Taking into account the value of the friction coefficient and the physical and mechanical properties, the most promising material is a ceramic with the addition of TiB2 or MoO3 with CaO.

PL

Przedstawiono wyniki badań dotyczących spiekania ceramiki o osnowie Al2O3Ti(C,N) z dodatkami faz poślizgowych. Scharakteryzowano właściwości mechaniczne i tribologiczne wytworzonych materiałów. Spośród faz określanych jako poślizgowe do badań wykorzystano następujące materiały: MoS2, WS2, CaSO4, SrSO4 oraz MoO3 i CaO. Biorąc pod uwagę niski współczynnik tarcia ceramiki o osnowie TiB2, wytworzono również ceramikę Al2O3Ti(C,N) z dodatkiem wysokotopliwej fazy TiB2. Materiały spiekane metodą SPS odznaczały się wartościami gęstości względnej od 93 do 99%. W przypadku materiałów z dodatkiem 10 i 30% TiB2 wartości gęstości względnej, modułu Younga oraz twardości HV1 były zbliżone bądź równe wartościom materiału bazowego. Dla pozostałych dodatków moduł Younga wynosił od 74% do 83%, a twardość od 62 do 76% wartości modułu i twardości materiału Al2O3-Ti(C,N). Niezależnie od rodzaju dodatku i jego udziału objętościowego obniżono współczynnik tarcia od 49 do 86% wartości współczynnika tarcia materiału bazowego. Najniższą wartość współczynnika tarcia zmierzono dla materiału po spiekaniu SPS z dodatkiem WS2. Materiał ten jednak odznaczał się względnie niskim modułem Younga oraz twardością. Biorąc pod uwagę wartość współczynnika tarcia oraz właściwości fizyczne i mechaniczne, najbardziej obiecującym materiałem jest ceramika z dodatkiem TiB2 oraz MoO3 i CaO.

12

The selection of phase composition of silicon nitride ceramics for shaping with the use of EDM machining

Putyra P., Laszkiewicz-Łukasik J., Wyżga P., Podsiadło M., Smuk B.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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Vol. 48, nr 1

35--40

EN

Purpose: The purpose of this study is the selection of phase composition of Si3N4 matrix ceramics with the addition of conducting phases so as to make shaping of those materials possible by means of electro discharge machining (EDM). Silicon nitride matrix materials with the addition of oxide phases (Al2O3, MgO, ZrO2) and conducting phases (TiB2, TiN) were sintered by the method of SPS (Spark Plasma Sintering). Additionally the effect of oxide phases on silicon nitride sintering capacity, the value of electric resistance of nitride ceramics depending on the addition of a conducting phase and the effect of sintering parameters on selected features of produced materials were determined. Design/methodology/approach: Materials were sintered with the use of a SPS device marked with FCT-HP D 5. Apparent density Pp was measured by the hydrostatic method. Hardness was determined by the Vicker’s method at the load of 980.7 mN with the use of a Future Tech Corp digital hardness tester FM7. For the purpose of those tests a surface was prepared with the use of a Struers cutting grinder ACUTOM. Measurements of Young’s modulus for sintered samples were carried out using a ultrasonic method of transverse and longitudinal wave speed measurement with the use of a Panametrics Epoch III detector. Resistance measurement was done with the use of Wheatstone and Thomson technical bridges. Findings: The addition of titanium nitride had no effect on the reduction of electric resistance of Si3N4 matrix ceramics. The lack of electric conductivity of those materials is the result of used additions influencing sintering capacity, mainly magnesium oxide. Si3N4 matrix materials with the addition of titanium diboride are characterised by low electrical resistance with high physical and mechanical features maintained. Electric conductivity of those materials and the initial electro discharge cutting attempts prove that it is possible to shape Si3N4 matrix ceramic materials with the addition of a TiB2 phase with the use of EDM process. Practical implications: The use of EDM will enable the production of elements with complicated shapes (impossible to achieve by other shaping methods) from ceramic materials (with Si3N4 matrix). Originality/value: By the appropriate selection of a conducting phase addition it is possible to increase electric conductivity of silicone nitride matrix ceramics, for which it is possible to shape products by means of electro discharge machining.

13

Alumina-Ti(C,N) ceramics with TiB2 additives

Putyra P., Podsiadło M., Smuk B.

Archives of Materials Science and Engineering

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2011

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Vol. 47, nr 1

27-32

EN

Purpose: The aim of the study presented in this article is to determine the effect of TiB2 addition on the selected properties of ceramic tool materials. The effect of titanium diboride additives on the density, porosity, Young’s modulus and Vickers hardness of Al2O3-Ti(C,N) matrix ceramics was determined. Design/methodology/approach: Al2O3-Ti(C,N) ceramics with TiB2 addition were sintered by SPS method. Materials for SPS sintering were pressed in graphite die with pressure of 35 MPa. The max. pressure was obtained after 10 minutes. Sinter process was operated in nitrogen atmosphere. Density, Vickers hardness and Young’s modulus was determined for these materials. The materials were also subjected to tribological analysis. The results were compared with the properties of Al2O3-Ti(C,N) matrix material. Findings: The use of SPS-method in the production of ceramic materials is possible reduce sintering temperature and sintering time. Depending on the TiB2 additives used, the relative density values of individual materials were in the range of 94.4% to 97.7%. Young’s modulus values for these materials were in the range of 392 GPa to 414 GPa, and Vickers hardness in the range of 1966 to 2225 HV1. The results of tribological analysis showed a friction coefficient value for the matrix material of 0.51. For the other materials, the friction coefficient values were in the range 0.31 to 0.49. Practical implications: Ceramic materials with the addition of titanium diboride may be used in cutting tools. Study of the composition and production technology of such tools allows for the minimisation of the use of liquid cooling lubricants in the machining process and the achievement of higher cutting speeds. Originality/value: Titanium diboride additives were added to the structure, resulting in a reduced coefficient of friction, which was measured at between 61% and 96% of the base material coefficient.

14

Analysis of residual stresses using the sin2Ψ method for Al2O3 materials before and after grinding and heat treatment processes

Putyra P., Skrzypek S., Smuk B., Podsiadło M.

Materiały Ceramiczne

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2010

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T. 62, nr 3

301-306

EN

This work presents the results of analysis of residual stresses generated at various stages of production of Al2O3 sinters (sintering, mechanical processing). Residual stresses were determined by the g-sin2Ψ X-ray method. The process of ceramic sintering of Al2O3 was carried out at varying parameters: temperature and heating time, heating rate, cooling rate. After mechanical processing (grinding), the materials were subjected to heat treatment, consisting of heating to temperatures in the range of 600 - 1200 °. In order to determine the mechanical properties of the materials, HV30, HV0.3 and HV0.1 hardness measurements were made. K(Ic) and HVG stress intensity index values were also determined.

PL

W pracy zaprezentowano wyniki analizy naprężeń resztkowych powstających na różnych etapach produkcji spieków Al2O3 (spiekanie, obróbka mechaniczna). Naprężenia resztkowe oznaczono rentgenowską metodą g-sin2Ψ. Spiekanie ceramiki Al2O3 przeprowadzono przy zróżnicowanych parametrach procesu - temperatura i czas ogrzewania, szybkość ogrzewania i studzenia. Po obróbce mechanicznej (szlifowanie) materiały poddano obróbce cieplnej polegającej na ogrzewaniu do temperatury z zakresu 600 - 1200 stopni C. Aby określić właściwości mechaniczne zmierzono twardość HV30, HV0.3 i HV0.1 materiałów. Oznaczono też wartości współczynników intensywności naprężeń K(Ic) i HVG.

15

Alumina composites with solid lubricant content

Putyra P., Podsiadło M., Smuk B.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 41, nr 1-2

34-39

EN

Purpose: The aim of the study presented in this article is to determine the effect of the addition of solid lubricating substances on the selected properties of ceramic tool materials. The effect of tested lubricant additives on the density, porosity, Young’s modulus and Vickers hardness of Al2O3-based ceramics with Ti(C,N) was determined. Design/methodology/approach: Ceramic materials based on aluminium oxide with the addition of solid lubricating substances. Materials were obtained by uniaxial compression with the addition of sliding substances, then isostatically pressed, and dried. The sintering process was carried out at a temperature of 1750°C under high vacuum conditions. Density, Vickers hardness and Young’s modulus was determined for these materials. The materials were also subjected to tribological analysis. The results obtained were compared with the properties of ceramic material based on Al2O3 + 30 mass.% Ti(C,N), from which tool materials were made. Findings: The use of solid lubricating substances in the production of ceramic materials allowed a reduction in the coefficient of friction. Depending on the sliding additives used, the relative density values of individual materials were in the range of 85.3% to 92.3%. Young’s modulus values for these materials were in the range of 273 GPa to 343 GPa, and Vickers hardness in the range of 966 to 1373 HV1. The results of tribological analysis showed a coefficient of friction value for the base material of 0.51. For the other materials, the coefficient of friction values were in the range 0.28 to 0.41, the lowest value being for the material with the addition of BaZrO3. Practical implications: Ceramic materials with the addition of solid lubricating substances may be used in cutting tools. Study of the composition and production technology of such tools allows for the minimisation of the use of liquid cooling lubricants in the machining process and the achievement of higher cutting speeds. Originality/value: Ceramic materials intended for cutting tool blades were produced with the addition of materials of a layered structure or of high cleavage by free sintering. These materials were added to the structure, resulting in a reduced coefficient of friction, which was measured at between 55% and 75% of the coefficient of friction of the base material. The coefficient of friction was determined for friction pairs: ceramic material - high hardness steel ball.

16

The analysis of strength properties of ceramic preforms for infiltration process

Putyra P., Kurtyka P., Jaworska L., Podsiadło M., Smuk B.

Archives of Materials Science and Engineering

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2008

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Vol. 33, nr 2

97-100

EN

Purpose: The goal of this work is the optimization of sintering process of the ceramic preforms based on Si3N4 and Al2O3-Ti(C,N) materials. The influence of pore forming additives on porosity, microstructures and compressive strength are investigated. The aim of this study is to obtain the nitrides and carbides base preforms material for the infiltration process of molten aluminium alloys. Design/methodology/approach: The method of obtaining the silicon nitride and oxide-carbonitride porous preform for the infitration process is the free sintering process. The preforms were produced by the mixing of ceramic powders with organic binders, drying and sintering. Porosity, density were measured for the materials. Microstructure observation was carried out using scanning microscope. The compressive strength of Si3N4 and Al2O3-Ti(C,N) porous preforms were investigated. Findings: For sintered porous Si3N4 preforms, influence of the porous forming additives on material porosity is observed. Compressive strengths of Si3N4 were in the range of 2.9-4.8 MPa. The highest value of the compressive strength was obtained for Al2O3-Ti(C,N) preform with 8 wt.% of tylose and 25 wt.% of glykol. For these materials compressive strength were in the range of 13.2 up to 14.3 MPa. In spite of lower value of the compressive strength for Si3N4 preforms, this material exhibits high shock thermal resistance. Practical implications: Pressureless infiltration of molten metals into ceramics is the most cost-effective approach to liquid-metal processing of MMCs. Metal matrix composites are applied widely in aircraft production technologies and defence technology. Originality/value: Infiltration of molten metals into porous ceramic preforms is the only technique suitable for the fabrication of high volume fraction of ceramic materials in MMCs. Infiltration process generates thermal stresses in the ceramics preforms. The thermal shock resistance of Al2O3 is lower than Si3N4 or Al2O3-Ti(C,N) materials. New kinds of porous materials were obtained.

17

Nitride and carbide preforms for infiltration process

Sobczak N., Jaworska L., Podsiadło M., Smuk B., Nowak R., Kurtyka P., Twardowska A.

Archives of Materials Science and Engineering

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2007

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Vol. 28, nr 11

653-656

EN

Purpose: Infiltration of molten metals into porous ceramic preforms is the only technique suitable for the fabrication of high volume fraction of ceramic materials in MMCs. The most popular material for porous preforms is Al2O3 because of its low cost. Infiltration process generates thermal stresses in the Al2O3 preforms. The thermal shock resistance of Al2O3 is lower than for Si3N4 or Al2O3/TiC+TiN materials. The aim of this study is to obtain the nitride and carbide base preforms material for the infiltration process of molten aluminium alloys. Design/methodology/approach: The method of obtaining the silicon nitride and oxide-carbonitride porous preform for the infiltration process is the free sintering process. Some of selected properties of this material are presented. The preforms were produced by the mixing of ceramic powders with organic binders, followed by forming, drying and firing. Ceramic preforms of 65% porosity were produced. Microscopic investigations revealed good joints between the ceramic particles. Findings: The material consist of the base component (90 wt.% of α-Si3N4, 5 wt.% of Al2O3, 5 wt.% of Y2O3), which were mixed with 40 wt.% of polyethylene glycol 6000 (mixed in Turbula) porosity is 25.7 %. The higher value of porosity 66.6% was obtained for material with 20 wt.% tylose. The grain size of Si3N4 and method of the mixtures preparing (mixing with or without milling) have the significant influence on compacts' porosity. For 68 wt.% Al2O3, 2 wt.% ZrO2 and 30 wt.% Ti(C,N) with addition of glycol 6000, the value of porosity is 67%.-Si3N4 material produced shows strong bonding with aluminium and AlSi11 aluminium alloy. Practical implications: Pressureless infiltration of molten metals into ceramics is the most cost-effective approach to liquid-metal processing of MMCs. Metal matrix composites are applied widely in aircraft production technologies and defence technology. Originality/value: Compared to widely used alumina performs, those made from non-oxide ceramics demonstrate better physicochemical compatibility with aluminium alloys. New kinds of porous materials were obtained.

18

Środowisko farmer-Worker dla klastra komputerów PC : pracę wykonano w ramach projektu badawczego Nr 8T110a1117 finansowanego przez Komitet Badań Naukowych w latach 1999-2001

Podsiadło M.

Archiwum Informatyki Teoretycznej i Stosowanej

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2002

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T. 14, z. 3

245-260

PL

Niniejszy artykuł prezentuje oprogramowanie do tworzenia aplikacji rozproszonych działających w lokalnej sieci komputerów osobistych. Oprogramowanie przeznaczone jest do zastosowań wspomagających transmisje dużych ilości danych ze stosunkowo małymi opóźnieniami. Szczególnie dobrze nadaje się do tworzenia aplikacji opartych na strukturze farmer-worker, choć inne struktury są również możliwe. Artykuł opisuje strukturę oprogramowania, sposób jego wykorzystania oraz eksperymentalne oszacowania wydajności transmisji dla przykładowej sieci pięciu komputerów osobistych.

EN

The paper presents software tools for the creation of distributed applications working in a local area network of personal computers. The tools are intended for applications that require large amounts of data to be transmitted with relatively short delays. It is particularly suitable for the creation of applications based on the farmer-worker structure, although other structures can also be used. The structure of the software and its use are discussed. Data throughput is estimated based on experimental results for a network of five PC computers.

19

Zastosowania algorytmów genetycznych do generacji trajektorii robotów

Podsiadło M.

Studia z Automatyki i Informatyki

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1999

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T. 24

137-150

PL

W pracy dokonano przeglądu metod generowania trajektorii robotów opartych na algorytmach genetycznych. Omówiono krótko zagadnienie generowania trajektorii. Następnie przedstawiono przykłady ilustrujące metodę sieciową, metodę komórkową oraz metodę analizy geometrycznej.

EN

The paper contains a review of trajectory generation methods based on genetic algorithms. The task of trajectory generation has been briefly outlined. Then, several examples illustrating network method, cell method, and geometrical analysis method have been presented.