Wyniki wyszukiwania - Biblioteka Nauki

1

Characterization of the heat treatment MgB2 rods obtained by PIT technique with explosive consolidation method

100%

Orlińska N. , Zaleski A. , Wokulski Z. , Dercz G.

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2008

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tom Vol. 53, iss. 3

927-932

EN

Cu/Fe/MgB2 rods have been prepared by the modified PIT techniąue with expIosive consolidation method. In the next step, so obtained rods were additionally annealed. The heat treatments of the rods were performed at 750°C and 850°C for 1 hour in He atmosphere. The phase compositions, microstructure features were investigated by X-ray diffraction and scanning electron microscopy (SEM) techniques, while the values of lattice parameters were determined by Rietveld method. The contents of all invoIved phases were determined by Rietveld procedurę. The superconducting properties for a core MgB2 rods were also investigated by the AC susceptometry and SQUID magnetometry techniques. It was found that no impurity phases were formed in heat treatment processes of Cu/Fe/MgB2 rods. In addition, it was found that MgB2 powder was well consolidated. There were found some smali voids in the heat treated rods. The high critical temperaturę Tc of 38.7 K and high critical current density Jc ∼ 105 A/cm2 were obtained in both rods.

PL

W pracy omówiono proces otrzymywania wygrzewanych prętów nadprzewodzącego MgB2. W pierwszym etapie otrzymano pręty Cu/Fe/MgB2 zmodyfikowaną techniką PIT z konsolidacją metod wybuchową, które w kolejnym etapie poddano obróbce cieplnej. Proces wygrzewania prętów odbywał się w temperaturze 750°C oraz 850°C w czasie godziny, w atmosferze ochronnej helu. Otrzymane pręty poddawano badaniom metalograficznym i rentgenowskim z wykorzystaniem skaningowego mikroskopu elektronowego (SEM) oraz dyfraktometru rentgenowskiego firmy Philips model 1130/00. W oparciu o uzyskane dyfraktogramy rentgenowskie określono ilościowy udział faz wchodzących w skład badanego materiału oraz stosując metodę Rietvelda określono wartości parametru sieci ao i co. Badania magnetyczne AC podatności \ wykonano przy użyciu susceptometru AC, z kolei pomiary pętli histerezy namagnesowania przeprowadzono przy użyciu magnetometru SQUID. Przeprowadzona analiza fazowa prętów Cu/Fe/MgB2 wygrzewanych w temperaturze 750°C i 850°C nie ujawniła występowania obcych faz. Badania mikrostruktury ujawniły w wygrzewanych prętach MgB2 występowanie małej ilości pustek o małych rozmiarach. Pomiary magnetyczne ujawniły wysoką temperaturę krytyczną Tc = 38.7 K i wysoką krytyczną gęstość prądu Jc ∼ 105 A/cm2 (4.1 K, 0 T)

2

Microstructure investigations of Co-Si-B alloy after milling and annealing

100%

Nowosielski R. , Babilas R. , Dercz G. , Pająk L.

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2007

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tom Vol. 23, nr 1

59-62

EN

Purpose: The work presents the microstructure characterization of Co77Si11,5B11,5 metallic glass after high-energy ball milling and heat treatment processes. Design/methodology/approach: The studies were performed on ribbon prepared by melt spinning and this ground in high-energy vibratory ball mill. The tested ribbon and obtained powders were also annealed in specified heat treatment conditions. The morphology of the powder particles of milled ribbon was analyzed by using the confocal laser scanning microscope. The methods of X-ray diffraction were used for the qualitative phase analysis. The parameters of the individual diffraction line profiles were determined by PRO-FIT Toraya procedure. The average crystallite sizes and lattice distortions for Co phase were estimated using Williamson-Hall method. Findings: The studied Co77Si11,5B11,5 metallic glass in annealed state contains hexagonal Co crystalline phases emerged in amorphous matrix. The crystallite size of Co phase in as-cast sample lies in nanoscale. After annealing process the crystallite size increases to 72 nm and diminishes to 46 nm in the powder sample after 30 hours of milling. The milling causes decrease of the crystallite size and increase of lattice distortions of crystalline phase. The powder particles after 30 hours of milling are of spherical shape. Practical implications: The powder particles obtained after milling process of Co-based metallic glass could be suitable components in production of ferromagnetic nanocomposites. Originality/value: The obtained results confirm the utility of applied investigation methods in the microstructure analysis of powder materials with nanocrystalline phases.

3

Utlenienie wieloskładnikowego aluminidku żelaza na osnowie fazy FeAl

100%

Kulak K. , Kupka M. , Dercz G.

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tom Vol. 32, nr 4

510-513

PL

Szerokie zainteresowanie stopami na osnowie faz międzymetalicznych, w tym na bazie fazy FeAl, wynika z ich unikalnych właściwości fizykochemicznych, które wzbudziły uzasadnione oczekiwania na opracowanie nowej grupy wysokotemperaturowych materiałów konstrukcyjnych. W literaturze brak jest wyczerpujących informacji na temat wpływu dodatków stopowych na proces utleniania aluminidków żelaza. W pracy przedstawiono właściwości utleniania aluminidku żelaza (FeAl) z makrododatkiem Cr oraz mikrododatkami Zr i B, w zakresie temperatury od 700°C do 1100°C w ciągu do 200 h. Produkty procesu utleniania badano metodą dyfrakcji rentgenowskiej i za pomocą elektronowego mikroskopu skaningowego. Otrzymane wyniki porównano z danymi literaturowymi dla stopów FeAl. Stwierdzono, że dodatek chromu może przyczynić się do zwiększenia odporności na utlenianie aluminidku żelaza. Obserwowano miejscowe łuszczenie się zgorzeliny w temperaturze 1100°C. Pękanie zgorzeliny mogło być spowodowane przez naprężenia cieplne indukowane podczas chłodzenia stopu z temperatury utleniania. Oddziaływanie cyrkonu może poprawić przyczepność zgorzeliny do podłoża FeAl.

EN

Widely interest in alloys based on the matrix of ordered intermetallic phases, including on the FeAl base, due to their unique physicochemical properties, which excited a justified expectations of a development of new high-temperature construction materials. In a literature is not much information about influence of alloy additions on the oxidation process of iron aluminides. The paper presents the oxidation behaviour of iron aluminide (FeAl) with Cr macroaddition and Zr, B microadditions in the temperature range of 700°C to 1100°C, during up to 200 hours. The oxidation products were identified examined by X-ray diffraction (XRD) and using scanning electron microscopy (SEM). The results obtained have been compared with the data, available in the literature, for the FeAl alloys. It has been found that the chromium addition perhaps contributes to increasing the iron aluminide oxidation resistance. Limited scale spallation was obserwed at 1100°C. Scale failure can results from the thermal stresses in the scale induced during cooling of the alloy from the oxidation temperature. The zirconium action can caused of increased adhesion of the scale to the FeA l substrate.

4

Structural and quantitative analysis of die cast AE44 magnesium alloy

100%

Rzychoń T. , Kiełbus A. , Dercz G.

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2007

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tom Vol. 22, nr 2

43-46

EN

Purpose: The main objective of this study was development of determination of phase fraction methodology in cast magnesium alloy containing aluminum and rare earth elements. Design/methodology/approach: The study was conducted on magnesium alloy containing 4 % wt. aluminum and 4 % wt. mixture of rare earth elements (mischmetal) in the as-cast condition. The mischmetal includes cerium, lanthanum, neodymium and praseodymium. In this study, several methods were used such as: optical light microscopy, quantitative metallography, scanning electron microscopy and X-ray diffraction. The Rietveld method with Hill and Howard procedure was applied for determination of lattice parameters and phase abundance. Findings: The microstructure of investigated alloy consists of alpha-Mg solid solution, globular, lamellar and acicular precipitations of Al11RE3 and Al2RE phases. The results show that the accurate determination of phase contents in AE44 alloy can not perform using quantitative metallography. In this purpose X-ray investigations should be applied. Research limitations/implications: Developed methodology will be used to quantitative phase analysis of investigated alloy after creep tests and die cast with different parameters. Practical implications: AE44 magnesium alloy is used in automotive industry. Moreover, this alloy has a new potential application and results of investigations may be useful for preparing optimal technology of die casting. Originality/value: Procedure described in this paper may be useful as the best experimental techniques for quantitative phase analysis of the intermetallic phases occuring in the AE series magnesium alloys.

5

Microstructure Evolution of TI/ZRO2 and TI/AL2O3 Composites Prepared by Powder Metallurgy Method

100%

Dercz G. , Matuła I. , Gurdziel W. , Kuczera N.

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6

Technology and Dielectric Properties of the KNLN Doped with Nd3+ and Pr3+ Ions

89%

Bochenek D. , Osińska K. , Mankiewicz M. , Niemiec P. , Dercz G. , Bochenek D. , Osińska K. , Mankiewicz M. , Niemiec P. , Dercz G.

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nr 3

7

Structural and Mössbauer spectroscopy studies of metallic powders Fe-Al-Cr-X (X =Ni, Mo) obtained by the self-decomposition method

88%

Hanc A. , Frąckowiak J. , Binczyk F. , Dercz G. , Pająk L.

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2008

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tom Vol. 29, nr 2

86-88

EN

The Fe-Al-Cr and Fe-Al-Cr-X X=(Ni,Mo) metallic powders produced by the self-decomposition method were examined by X-ray powder diffraction, scanning electron microscopy and Mössbauer spectroscopy. The determined crystal structure parameters and the hyperfine interaction parameters are presented and discussed. The results of solute addition (X = Ni, Mo) in the investigated Fe-Al-Cr metallic powders are presented and discussed. The nickel and molybdenum additions modifies the phase composition of the studied materials and changes hyperfine parameters. The investigated Fe-Al-Cr powders produced by the self-decomposition method contain two phases, both of the B2 type structure: Fe(Cr)AlX and Cr(Fe)AlX enriched in Fe and Cr respectively and as well small amount of FexCr1- x. The Fe-Al-Cr-X (X =Ni, Mo) metallic powders and contain the besides the main Fe2Al5(X) phase and (FeX)Al8Cr5 phase. X-ray diffraction and SEM studies confirm the results of the Mössbauer spectroscopy.

PL

W pracy przedstawiono wyniki badań struktury, mikrostruktury oraz parametrów oddziaływań nadsubtelnych proszków metalicznych Fe-Al-Cr oraz Fe-Al-Cr-X X = (Ni, Mo) o składzie zestawionym w tabeli 1. Badania przeprowadzono stosując metodę dyfrakcji rentgenowskiej, skaningowej mikroskopii elektronowej oraz spektroskopii efektu Mössbauera. Wykazano, że proszki metaliczne Fe-Al-Cr stanowiąmateriał dwufazowy. Zidentyfikowane fazy Fe(Cr)AlX i Cr(Fe)AlX zawierają zmienną koncentrację atomów żelaza oraz chromu, przy czym każdą z faz charakteryzuje uporządkowana struktura typu B2. Wyniki badań analizy dyfraktogramów oraz mikroanalizy rentgenowskiej wykazały także występowanie drobnych wydzieleń fazy FexCr1-x. Wprowadzone atomy domieszek modyfikują strukturę badanych materiałów. Proszki metaliczne Fe-Al-Cr-X (X = Ni, Mo) są materiałem wielofazowym stwierdzono występowanie faz na osnowie międzymetalicznej Fe2Al5. W badanych proszkach metalicznych stwierdzono występowanie fazy Fe2Al5(X) oraz (FeX)Al8Cr5, każda z tych faz zawiera w swoim składzie zastosowane domieszki - nikiel oraz molibden. Metodą spektroskopii efektu Mössbauera izotopu 57Fe określono parametry oddziaływań nadsubtelnych, tj. przesunięcie izomeryczne-(IS) oraz rozszczepienie kwadrupolowe-(QS) (tab. 2), charakteryzujące zidentyfikowane na podstawie badań strukturalnych faz.

8

Mössbauer and structure studies on metallic powders from Fe-Al-X (X = Ni, Cu, Cr)

88%

Hanc A. , Dercz G. , Pająk L. , Frąckowiak J. , Kansy J.

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2008

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tom Vol. 31, nr 1

20-24

EN

Purpose: The Fe-Al-X and Fe-Al-Ni-X metallic powders produced by the self-decomposition process and then intensive grinding in an electro-magneto-mechanical mill with X = Fe, Ni, Cu, Cr additions was determined by applying the X-ray powder diffraction (XRD) and Mössbauer spectroscopy. Design/methodology/approach: The X-ray diffraction and Mössbauer spectroscopy were applied to identify the phase composition of the studied materials. Ordering process was analyzed by X-ray diffraction methods and Mössbauer spectroscopy. Findings: The effects of solute addition (X = Fe, Ni, Cu, Cr) in the investigated Fe-Al and Fe-Al-Ni metallic powders are presented and discussed. Good correlation between the results of X-ray diffraction and Mössbauer spectroscopy studies was obtained. Research limitations/implications: The Mössbauer spectroscopy appeared to be usefull in the identification of phase composition in studied materials. Application of Rietveld refinement method enabled the verification of this composition. Practical implications: The information on the phase transformation during the self-decomposition process and then intensive grinding in an electro-magneto-mechanical mill with additions are of prime importance for technological processing. Originality/value: All the phases that exist in the milled material contain high concentrations of aluminium (over 50 at. %) and have the ordered B2 structure. Alloying additions (Ni, Fe, Cu, Cr) and intensive high-energy grinding in the EMM mill modified the chemical and phase composition of the Fe-Al-X and Fe-Al-Ni-X samples.

9

Barium ferrite powders prepared by milling and annealing

88%

Nowosielski R. , Babilas R. , Dercz G. , Pająk L. , Wrona J.

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2007

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tom Vol. 22, nr 1

45-48

EN

Purpose: Microstructure and magnetic properties analysis of barium ferrite powder obtained by milling and heat treatment. Design/methodology/approach: the milling process was carried out in a vibratory mill, which generated vibrations of the balls and milled material in side the container during which their collisions occur. After milling process the powders were annealed in electric chamber furnace. The X-ray diffraction methods were used for qualitative phase analysis of studied powder samples. The distribution of powder particles was determined by a laser particle analyser. The magnetic hysteresis loops of examined powder material were measured by resonance vibrating sample magnetometer (R-VSM). Findings: The milling process of iron oxide and barium carbonate mixture causes decrease of the crystallite size of involved phases. The X-ray investigations of tested mixture milled for 30 hours and annealed at 950 degrees centigrade enabled the identification of hard magnetic BaFe12O19 phase and also the presence of Fe2O3 phase in examined material. The Fe2O3 phase is a rest of BaCO3 dissociation in the presence of Fe2O3, which forms a compound of BaFe12O19. The best coercive force (HC) for mixture of powders annealed at 950 degrees centigrade for 10,20 and 30 hours is 349 kA/m, 366 kA/m and 364 kA/m, respectively. The arithmetic mean of diameter of Fe2O3 and BaCO3 mixture powders after 30 hours of milling is about 6.0 micrometres. Practical implications: The barium ferrite powder obtained by milling and annealing can be suitable components to produce sintered and elastic magnets with polymer matrix. Originality/value: The results of tested barium ferrite investigations by different methods confirm their utility in the microstructure and magnetic properties analysis of powder materials.

10

Crystallization of Fe72B20Si4Nb4 metallic glasses ribbons

88%

Nowosielski R. , Babilas R. , Griner S. , Dercz G. , Hanc A.

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2009

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tom Vol. 34, nr 1

15-22

EN

Purpose: The paper presents a crystallization process of Fe-based amorphous materials. The aim of work is presentation of the influence of annealing temperature on structural changes and magnetic properties of Fe72B20Si4Nb4 metallic glasses. Design/methodology/approach: The studies were performed on metallic glasses as ribbons. Crystallization behaviour of the studied alloy was examined by differential thermal analysis (DTA), X-ray diffraction (XRD), transmission electron microscopy (TEM) and Mössbauer spectroscopy methods. The soft magnetic properties examination of tested material contained magnetic permeability, coercive field, saturation induction and magnetic after-effects measurements. Findings: The XRD, TEM and Mössbauer spectroscopy investigations revealed that the studied alloy in as-cast state was amorphous. A two stage crystallization process was observed for studied material. The first stage of crystallization corresponding to the partial crystallization of .-Fe phase was followed by the formation of iron borides. It has shown that appropriate increasing of annealing temperature, significantly improved soft magnetic properties of examined alloy. The maximum of initial magnetic permeability is correlated with a minimum of coercive field. Practical implications: The soft magnetic properties of metallic glasses can be optimized by applying the appropriate conditions of heat treatment. Originality/value: The applied investigation methods are suitable to determine the changes of structure and the improvement of soft magnetic properties of examined Fe-based alloy in comparison with as-cast state.

11

Microstructure and magnetic properties of BaFe12O19 powder

88%

Nowosielski R. , Babilas R. , Dercz G. , Pająk L. , Skowroński W.

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2008

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tom Vol. 27, nr 1

51-54

EN

Purpose: Analysis of microstructure and magnetic properties of BaFe12O19 powder obtained by milling and annealing of Fe2O3 and BaCO3 precursors. Design/methodology/approach: The mixture of iron oxide (Fe2O3) and barium carbonate (BaCO3) powders was used to obtain BaFe12O19 powder by using high-energy ball milling and heat treatment processes. The X-ray diffraction methods were used for qualitative, quantitative phase analyses and for crystallite size and lattice distortion determination. The thermal properties of the studied powders were analyzed using the differential thermal analysis (DTA). The magnetic properties of examined powder material were studied by resonance vibrating sample magnetometer (R-VSM). The size of powder particles was determined by a laser particle analyzer. Findings: The milling process of iron oxide and barium carbonate mixture causes decrease of the crystallite size of involved phases. The X-ray diffraction investigations of Fe2O3 and BaCO3 mixture milled for 50 hours and annealed at 850, 900, 950 and 1000*C enabled the identification of hard magnetic BaFe12O19 phase and also small amount of Fe2O3 phase. The magnetic properties of studied powders are dependent on temperature of their annealing. The sample annealed at 1000*C has the best hard magnetic properties from all studied samples. The content changes of hard magnetic phase (BaFe12O19) with the increase of annealing temperature results in the improvement of hard magnetic properties. Practical implications: The BaFe12O19 powder can be suitable component to produce sintered hard magnetic materials. Originality/value: The study results of BaFe12O19 powders confirm the utility of applied investigation methods in the microstructure and magnetic properties analysis of powder materials.

12

Structure and properties of barium ferrite powders prepared by milling and annealing

88%

Nowosielski R. , Babilas R. , Dercz G. , Pająk L. , Wrona J.

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2007

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tom Vol. 28, nr 12

735-742

EN

Purpose: Microstructure and magnetic properties analysis of barium ferrite powder obtained by milling and heat treatment Design/methodology/approach: The milling process was carried out in a vibratory mill, which generated vibrations of the balls and milled material inside the container. After milling process the powders were annealed in electric chamber furnace. The X-ray diffraction methods were used for qualitative phase analysis of studied powder samples. The morphology of Fe2O3 and BaCO3 powders after milling was analyzed using the scanning electron microscopy (SEM) method. The distribution of powder particles was determined by a laser particle analyzer. The magnetic hysteresis loops of examined powder material were measured by resonance vibrating sample magnetometer (R-VSM). Findings: The milling process of iron oxide and barium carbonate mixture causes decrease of the crystallite size of involved phases and leads to increase the content of Fe2O3 phase and decrease of BaCO3 content. Milling process causes enriching of surface layer of powder particles by Fe2O3. The X-ray investigations of tested mixture milled for 30 hours and annealed at 950*C enabled the identification of hard magnetic BaFe12O19 phase and also the presence of Fe2O3 phase in examined material. The Fe2O3 phase is a rest of BaCO3 dissociation in the presence of Fe2O3, which forms a compound of BaFe12O19. The best coercive force for the mixture of powders annealed at 950oC for 10, 20 and 30 hours is 349 kA/m, 366 kA/m and 364 kA/m, respectively. From morphology images and distribution of powder particle size it can be concluded, that the size of tested powder particles increases with increasing time of milling process. The increase of milling time up to 20 hours leads to joining of smaller particles in bigger ones; agglomerates are formed. Practical implications: The barium ferrite powder obtained by milling and annealing can be suitable component to produce sintered and elastic magnets with polymer matrix. Originality/value: The results of tested barium ferrite investigations by different methods confirm their utility in the microstructure and magnetic properties analysis of powder materials.

13

Otrzymywanie powłok konwersyjnych na cynku metodą pasywacji anodowej

88%

Maciej A. , Simka W. , Dercz G. , Nawrat G. , Piotrowski J.

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2011

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tom nr 7

477-481

PL

W pracy przedstawiono wyniki badań dotyczących elektrochemicznego otrzymywania powłok konwersyjnych na podłożu cynkowym. Proces prowadzono w roztworze wodorotlenku sodu w zakresie stężenia od 10 do 200 g/dm3 oraz przy różnych warunkach prądowych. W zależności od stosowanych warunków procesu otrzymano białe lub czarne powłoki konwersyjne. W przypadku wykorzystania do obróbki anodowej najbardziej stężonego roztworu elektrolitu zaobserwowano efekt wybłyszczenia powierzchni. Określono mikrostrukturę otrzymanych powłok, ich skład chemiczny, chropowatość oraz odporność korozyjną.

EN

Results of investigations applying to formation of conversion coatings on zinc substrate have been showed in this work. The process was performed in sodium hydroxide solution in the range of concentration from 10 to 200 g/dm3 and in different electric current conditions. Depending on the applying parameters the black and white conversion coatings were obtained. The brightening effect was observed in the case of usage for the anodic treatment the most concentrated electrolyte solution. The mictrostructure of received coatings, their phase composition, roughness and corrosion resistance have been determined.

14

The Influence of Passivation Type on Corrosion Resistance of Ti15Mo Alloy in Simulated Body Fluids / Wpływ Rodzaju Pasywacji Powierzchni Stopu Ti15Mo Na Jego Odporność Korozyjną W Środowisku Płynów Ustrojowych

88%

Dercz G. , Łosiewicz B. , Szklarska M. , Rak J. , Simka W.

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15

Microstructure and Properties of YSZ Coatings Prepared by Plasma Spray Physical Vapor Deposition for Biomedical Application

76%

Barczyk J. , Dercz G. , Matuła I. , Góral M. , Maszybrocka J. , Bochenek D. , Gurdziel W.

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16

Microstructure Analysis of Equiatomic Multi-Component NI20TI20TA20CO20CU20 Alloy

76%

Glowka K. , Zubko M. , Świec P. , Prusik K. , Dercz G. , Stróż D.

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nr 2

17

Microstructure of Multi-Component NI35TI35TA10CO10CU10 Alloy

76%

Glowka K. , Zubko M. , Świec P. , Prusik K. , Dercz G. , Matyja E. , Stróż D.

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18

Opracowanie metod charakteryzowania struktury i właściwości materiałów gradientowych

63%

Łągiewka E. , Budniok A. , Lelątko J. , Goryczka T. , Karolus M. , Gigla M. , Popczyk M. , Wykpis K. , Bierska-Piech B. , Dercz G.

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2008

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tom Vol. 29, nr 2

57-70

PL

Praca dotyczy możliwości charakteryzowania struktury, otrzymywania oraz właściwości elektrochemicznych materiałów gradientowych. Wyniki były uzyskane w trakcie realizacji zadania 5 projektu zamawianego PBZ/100/5/2004. Problemy badań struktury obejmowały niektóre metody rentgenowskiej analizy dyfrakcyjnej (SKP, reflektometria) i metody mikroskopii elektronowej. Do otrzymywania materiałów gradientowych zastosowano metodę elektrolitycznego osadzania. Właściwości materiałów, efektywność wydzielania wodoru analizowano metodami klasycznymi i elektrochemiczną spektroskopią impedancyjną. Stwierdzono, że w badaniach struktury materiałów gradientowych należy łączyć metody SKP i reflektometrię, szczególnie dla materiałów o liniowym gradiencie. W wyznaczeniu parametrów sieciowych faz i wielkości ich krystalitów należy w metodzie SKP stosować poprawki na zmianę położenia i szerokość refleksu dyfrakcyjnego. W analizie materiałów gradientowych techniką mikroskopii elektronowej należy posługiwać się opracowanym programem komputerowym ElDif i HOLZAK. Programy te znacznie ułatwiają analizę fazową oraz wyznaczenie stałej sieciowej. Za pomocą techniki CBED i techniki obrazów fazowych istnieje możliwość wyznaczania naprężeń w materiałach gradientowych. W badaniach elektrochemicznych wykazano, że metodą elektrolitycznego osadzania istnieje możliwość, dla pewnych układów metali, otrzymać powłoki charakteryzujące się liniowym lub skokowym gradientem zmiany składu chemicznego. Efektywność wydzielania wodoru na powłokach gradientowych jest znacznie lepsza niż na powłokach otrzymanych z oddzielonych ich składników. W pracy wykazano pełną przydatność elektrochemicznej spektroskopii impe-dancyjnej, zarówno w badaniach procesu otrzymywania materiałów gradientowych, jak i w badaniach ich właściwości.

EN

The work presents results, which were focused on studies of possibility in: structure characterization, method of production and electrochemical properties of gradient materials. Results were obtained during realization of the grant PBZ/100//5/2004. The problems of structure investigations included some methods of X-ray diffraction analysis (SKP, reflectometry) and methods of electron microscopy. The gradient materials were obtained by electrochemical deposition method. The properties of these materials like the efficiency of hydrogen evolution reaction were analyzed using classical methods and the electrochemical impedance spectroscopy. It was ascertained that for investigation of structure of gradient materials, the SKP and reflectometry methods should be connected, particularly in the case of materials with linear gradient. In order to determined the phase lattice parameters and the size of crystallites, the correction of position and width of diffraction reflexes in the SKP method should be applied. The elaborated EIDif and HOLZAK computer programs should be used for analysis of gradient materials by the electron microscope technique. These programs considerably facilitate the phase analysis and lattice constant determination. Determination of stresses in gradient materials is possible by applying CBED and phase picture techniques. On the base of the electrochemical research it was ascertained, that the layers with linear and alternate gradient of chemical composition for some metals system, may be obtained by electrochemical deposition. The efficiency of the hydrogen evolution process and of gradient materials is considerable better in comparison with individual component layers. The suitability of electrochemical impedance spectroscopy in investigations of production process and the properties of gradient materials, were stated in this work.