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1

Fabrication and Characterization of Al6061-Nano Al2O3 Composites by Ultrasonic Assisted Stir Casting followed by Heat Treatment and Hot Forging

Purohit Rajesh, Qureshi M.M.U., Kumar Ashish, Mishra Abhishek, Rana R.S.

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 2

791--798

EN

The present work comprises the development of Al6061/nano Al2O3 composites with 0 to 4 weight percent in steps of 0.5 wt. % of nano alumina particles by using ultrasonic assisted stir casting. Casted samples were subjected to heat treatment and hot forging. Further forged and heat-treated gear blanks of nano Al2O3 (0 to 3.0 weight %) reinforced nanocomposites were machined to make spur gears for the wear test. The results have shown that nano Al2O3 reinforcement in the Al6061 matrix with heat treatment and forging improves the hardness and compressive strength up to 3.5 wt. %, after that, it starts decreasing because of the agglomeration of nano alumina particles. SEM results reveal grain refinement of the pure alloy after reinforcement. Removal of porosity and voids observed after forging operation. Wear resistance increasing with incorporation of Al2O3 nanoparticles in base alloy, reinforcement wt. %, precipitation hardening and hot forging also improves wear resistance and mechanical properties. These composites have widespread applications in gear, brake discs, crankshaft, clutch plates, pistons, and other components of automobiles and aircraft structures.

2

The character of the structure formation of model alloys of the Fe-Cr-(Zr, Zr-B) system synthesized by powder metallurgy

Duriagina Z. A., Romanyshyn M. R., Kulyk V. V., Kovbasiuk T. M., Trostianchyn A. M., Lemishka I. A.

Journal of Achievements in Materials and Manufacturing Engineering

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2020

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Vol. 100, nr 2

49--57

EN

Purpose: The purpose of the work is to synthesize and investigate the character of structure formation, phase composition and properties of model alloys Fe75Cr25, Fe70Cr25Zr5, and Fe69Cr25Zr5B1. Design/methodology/approach: Model alloys are created using traditional powder metallurgy approaches. The sintering process was carried out in an electric arc furnace with a tungsten cathode in a purified argon atmosphere under a pressure of 6·104 Pa on a water cooled copper anode. Annealing of sintered alloys was carried out at a temperature of 800°C for 3 h in an electrocorundum tube. The XRD analysis was performed on diffractometers DRON-3.0M and DRON-4.0M. Microstructure study and phase identification were performed on a REMMA-102-02 scanning electron microscope. The microhardness was measured on a PMT-3M microhardness meter. Findings: When alloying a model alloy of the Fe-Cr system with zirconium in an amount of up to 5%, it is possible to obtain a microstructure of a composite type consisting of a mechanical mixture of a basic Fe2(Cr) solid solution, solid solutions based on Laves phases and dispersive precipitates of these phases of Fe2Zr and FeCrZr compositions. In alloys of such systems or in coatings formed based on such systems, an increase in hardness and wear resistance and creep resistance at a temperature about 800°C will be reached. Research limitations/implications: The obtained results were verified during laser doping with powder mixtures of appropriate composition on stainless steels of ferrite and ferrite-martensitic classes. Practical implications: The character of the structure formation of model alloys and the determined phase transformations in the Fe-Cr, Fe-Cr-Zr, and Fe-Cr-B-Zr systems can be used to improve the chemical composition of alloying plasters during the formation of ferrite and ferrite-martensitic stainless steel coatings. Originality/value: The model alloys were synthesized and their phase composition and microstructure were studied; also, their microhardness was measured. The influence of the chemical composition of the studied materials on the character of structure formation and their properties was analysed.

3

Comparison of corrosion resistance in physiological saline solution of two austenitic stainless steels – 316LV and REX734

Romańczuk E., Oksiuta Z.

Acta Mechanica et Automatica

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2017

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Vol. 11, no. 2

91--95

EN

In this work two austenitic stainless steels, REX734 and 316LV were tested in terms of their microstructure and corrosion properties. The REX734 is a newer generation stainless steel, with modified chemical composition, in comparison to the 316LV grade. Potentiodynamic study of corrosion resistance was conducted in physiological saline solution (0.9% NaCl solution). In spite of the similarities of microstructure, grain size and phase structure in both materials, the corrosion tests revealed that the REX734, with lower nickel and higher nitrogen content, had better corrosion resistance than 316LV. Repassivation potential in the REX734 was almost six times higher than for the 316LV steel. Superior corrosion resistance of the REX734 steel was also confirmed by surface observations of both materials, since bigger and more densely distributed pits were detected in 316LV alloy.

4

Chemical weathering of talus slopes: the example of slopes in the Brattegg Valley, Sw Spitbergen

Senderak K., Wąsowski M.

Studia Geomorphologica Carpatho-Balcanica

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2016

|

Vol. 50

105—122

EN

This paper presents the results of hydrogeochemical surveys carried out in the non-glaciated part of the Brattegg Valley near Hornsund Fjord (SW Spitsbergen). The aim of the study was to indicate places in periglacial zone with the greatest intensity of chemical weathering. The valley was divided into five zones where 11 observation sites were selected. The physico-chemical parameters of water were measured in situ. Water chemical composition was defined using ion chromatograph and mineral composition was obtained based on X-ray diffraction analysis. The results of the study show that in the studied valley, talus slopes are the most dynamic environment of the periglacial zone and are typified by the greatest intensity of chemical weathering.

5

Nowe możliwości badawcze Centrum Badań Materiałów i Technologii Spiekania SINTERCER

Putyra P., Jaworska L., Klimczyk P., Cyboroń J., Cygan S., Skrabalak G.

Mechanik

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2016

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R. 89, nr 5-6

430--437

PL

Przedstawiono założenia realizowanego przez Instytut Zaawansowanych Technologii Wytwarzania międzynarodowego projektu pt.: „Rozwój centrum procesów spiekania i wymiana wiedzy dotyczącej metod spiekania specjalnych materiałów kompozytowych o osnowie ceramicznej w warunkach braku równowagi termodynamicznej” – REGPOT-CT-2013-316232-SINTERCER. Scharakteryzowano zakres prac obejmujących modernizację aparatury do spiekania wysokociśnieniowego materiałów supertwardych oraz przedstawiono cel i możliwości aparatury badawczej zakupionej w ramach projektu.

EN

Presented are the requirements for the international cooperation Project entitled: “Development of a SINTERing CEntRe and exchange of know-how on the methods of advanced ceramic composite materials sintering process under non-equilibrium conditions of, REGPOT-2012-2013-1 EU FP7 Research Potential” – REGPOT-CT-2013-316232-SINTERCER. The scope of modernization of equipment used for high-pressure sintering of super-hard materials is specified as well as the purpose and capacities of the research equipment procured under this project.

6

Synthesis and study of structural properties of Sn doped ZnO nanoparticles

Javid M. A., Rafi M., Ali I., Hussain F., Imran M., Nasir A.

Materials Science Poland

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2016

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Vol. 34, No. 4

741--746

EN

Pure and Sn-doped ZnO nanostructures were synthesized by simple chemical solution method. In this method we used zinc nitrate and NaOH as precursors. Sn doping content in ZnO was taken with the ratio 0, 5, 10, 15 and 20 percent by weight. Physical properties of Sn-doped ZnO powder were studied by XRD analysis which revealed that Sn doping had a significant effect on crystalline quality, grain size, intensity, dislocation density and strain. The calculated average grain size of pure ZnO was 21 nm. The best crystalline structure was found for 0 wt.%, 5 wt.% and 10 wt.% Sn doping as observed by FESEM and XRD. However, higher Sn-doping (> 10 wt.%) degraded the crystallinity and the grain size of 27.67 nm to 17.76 nm. The structures observed in FESEM images of the samples surfaces were irregular and non-homogeneous. EDX depicted no extra peak of impurity and confirmed good quality of the samples.

7

Structural, electrical and magnetic features of Kagomé YBaCo4O7 system

Bhat M. A., Zargar R. A., Modi A., Arora M., Gaur N. K.

Materials Science Poland

|

2016

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Vol. 34, No. 4

786--793

EN

Polycrystalline yttrium barium cobaltite (YBaCo4O7) powdered sample was prepared by conventional solid state reaction route using high purity yttrium oxide, barium carbonate and cobalt oxide. The as-prepared sample was characterized by XRD diffraction, SEM/EDAX, Raman analytical techniques, resistivity and magnetization measurements for structural, morphological, electrical and magnetic properties assessment. XRD pattern confirms the single phase formation of the sample without any impurity. SEM image shows the hexagonal growth of the crystal and EDAX spectrum reveals stoichiometric composition of as prepared sample. The variation in electrical resistivity from 90 K to 300 K follows the variable range hopping conductivity mechanism. The strong broad overlapped Raman peaks of Co–O and Y–O stretching and bending vibrations of tetrahedral CoO4 with included components of YO6 of octahedral symmetry are obtained at 542 cm-1, 486 cm-1 and 636 cm-1, 436 cm-1, respectively. DC magnetic susceptibility exhibits very weak ferromagnetism below 80 K and does not obey Curie-Weiss law.

8

XRD and morphology analyzes of high-nitrogen Fe-Cr-Mn alloy powders synthesized by mechanical alloying

Romańczuk E., Oksiuta Z.

Engineering of Biomaterials

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2016

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Vol. 19, no. 138 spec. iss.

95

9

Korozja zaczynu z żużla wielkopiecowego w wodnym roztworze (NH4)2SO4

Słomka-Słupik B., Podwórny J., Łukowiec D.

Cement Wapno Beton

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2016

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R. 21/83, nr 6

379--388

PL

Badania korozji zaczynu żużlowego, aktywowanego krzemianem sodu, w wodnym roztworze siarczanu amonu wykazały, że proces ten przebiega znacznie szybciej niż w roztworach innych siarczanów. Natomiast przebieg tego procesu jest zbliżony i polega na odwapnieniu fazy C-S-H z równoczesnym powstawaniem gipsu. Występują pewne różnice w przebiegu korozji, a mianowicie zaznacza się bardzo mała trwałość ettringitu, a jony glinu lokują się przejściowo w fazie C-S-H, aby następnie utworzyć bezpostaciowy wodorotlenek. Jony sodu, lokujące się w fazie C-S-H, przechodzą do roztworu w procesie odwapnienia tej fazy i, jako siarczan sodu, ulegają wyługowaniu z zaczynu. Szybki spadek pH powoduje, że jedynymi trwałymi fazami są: gips, kalcyt i wodorotlenek glinu.

EN

The sodium silicate activated slag paste corrosion in ammonium sulphate water solution tests have shown that the process has a much higher rate than in other sulphate solutions. However, the process itself is similar and the decalcifying of C-S-H phase is the main change, caused by Ca(OH)2 lack, with the simultaneous gypsum formation. Some differences in corrosion are occurring, namely the stability of ettringite is very low and aluminium ions are transitory incorporated in C-S-H phase, but during the decalcifying are then released to the solution, with the hydroxide formation. Sodium ions, are also bound in C-S-H phase, but are also released to the solution and in the form of sodium sulphate are lixiviate from the paste. The quick decrease of solution pH the stable phases became: gypsum, calcite and AH3.

10

Colour properties of pigments based on YMnO3

Burkovicova A., Dohnalova Z., Sulcova P.

Materiały Ceramiczne

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2015

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T. 67, nr 1

9--14

EN

Inorganic pigments of the YMnx(CuSn)1-xO3±δ (CuSn) and YMnx(NiSn)1-xO3±δ (NiSn) type, where x = 0.9, 0.5, 0.1, were prepared by wet mechanical activation. Influence of composition and calcination temperature on the colour properties, particle size distribution and phase purity was examined. The pigments were applied into a ceramic glaze and organic matrix. With the calcination temperature increasing from 1000 °C to 1200 °C and with the decreasing content of Mn, the colour of the pigment powders changed from black to dark green in case of CuSn and from black to dark brown in case of NiSn. Particle size distributions (PSD) of the prepared powders varied in the interval suitable for pigment applications. A complete solid solution (hexagonal YMnO3) was obtained only in the case of YMn0.9(CuSn)0.1O3±δ. The effect of mineralizers (AlF3, Na3AlF6, H3BO3, Na2CO3) on the colour properties and phase composition was also investigated. The prepared powders were compared with the industrially produced pigments.

PL

Wykorzystując aktywację mechaniczną na mokro, przygotowano nieorganiczne pigmenty typu YMnx(CuSn)1-xO3±δ (CuSn) i YMnx(NiSn)1-xO3±δ (NiSn), gdzie x = 0,9, 0,5, 0,1. Zbadano wpływ składu i temperatury kalcynacji na właściwości barwne, rozkład wielkości cząstek i czystość fazową. Pigmenty zastosowano w szkliwie ceramicznym i osnowie organicznej. Wraz ze zwiększaniem temperatury kalcynacji od 1000 °C do 1200 °C i zmniejszaniem zawartości Mn, barwa proszków zmieniała się od czarnej do ciemnozielonej w przypadku pigmentów CuSn i od czarnej do ciemnobrązowej w przypadku pigmentów NiSn. Rozkłady wielkości cząstek (PSD) przygotowanych proszków zmieniały się w zakresie odpowiednim do zastosowania w roli pigmentów. Tylko w przypadku YMn0,9(CuSn)0,1O3±δ otrzymano Wyłącznie roztwór stały (heksagonalny YMnO3). Zbadano również wpływ mineralizatorów (AlF3, Na3AlF6, H3BO3, Na2CO3) na właściwości barwne i skład fazowy. Przygotowane proszki porównano z przemysłowo wytwarzanymi pigmentami.

11

Zastosowanie mezoporowatej krzemionki jako adsorbentu dla teofiliny w układzie dostarczania substancji leczniczej

Moritz M

Przemysł Chemiczny

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2013

|

T. 92, nr 11

2093-2096

PL

Przedstawiono wpływ modyfikacji powierzchni krzemionki SBA-15 3-aminopropylotrietoksysilanem na proces adsorpcji i uwalniania teofiliny. Dokonano charakterystyki próbek z użyciem sorptometrii azotu, analizy dyfraktometrycznej (XRD) oraz spektroskopii odbiciowej. Wykazano, że modyfikacja krzemionki znacznie zwiększa pojemność adsorpcyjną nośnika i powoduje wydłużenie uwalniania leku.

EN

Mesoporous SiO2 was produced by decompn. of Si(OEt)4, modified with NH2(CH2)3Si(OEt)3 and used for adsorption of theophylline from Me2CHOH/CHCl3 soln. at room temp. The adsorbed theophylline was then released to water or aq. HCl soln. (concn. 0.1 mol/L) at 37±2°C. The modification of the SiO2 adsorbent resulted in an increase in its adsorption capacity by 60% and a decrease in the theophylline releasing rate.

12

An application of microscopic analyses in shale gas rock description

Leśniak G.

Nafta-Gaz

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2011

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R. 67, nr 5

321-325

EN

As a standard procedure for shale (reservoir rock for shale gas) in order to determine its mineral composition, XRD analysis is made. It is supplemented with petrographic analyses providing information not only about mineral content but also about distribution of minerals in rock (texture and structure). The information obtained from microscopic analyses considerably broadens our knowledge concerning analyzed rocks and is used in sedimentology, facies analysis, sedimentation basin analysis, assessment of reservoir properties, hydrocarbon migration paths as well as projecting the fracturing treatments.

PL

Standardowo dla łupków (skał zbiornikowych dla "shale" gazu) w celu oznaczenia składu mineralnego wykonuje się analizy XRD. Uzupełnieniem analiz XRD są analizy petrograficzne, dające informacje nie tylko o składzie mineralnym, ale również o rozłożeniu minerałów w skale (teksturze i strukturze). Informacje uzyskane z analiz mikroskopowych w znaczący sposób poszerzają naszą wiedzę o analizowanych skałach i są wykorzystywane w sedymentologii, analizie facjalnej, analizie rozwoju basenów sedymentacyjnych, ocenie własności zbiornikowych i dróg migracji węglowodorów oraz przy projektowaniu zabiegów szczelinowania.

13

The identification of carbide phases by XRD analysis as the method of assess the extent of the steel damage after long time in service

Pietryka I., Lisak J.

Archives of Foundry Engineering

|

2010

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Vol. 10, iss. 3 spec.

283--288

EN

After long time in service in contact in a superheated steam mechanical properties of materials decrease. Experiments revealed that the XRD analysis of electrochemically separated carbide phase is a rapid and informative method of evaluation the service condition of steel. Mechanical properties of ferritic and bainitic low-alloy steels are caused by many factors like: chemical composition, quantity and the kind of microstructural constituent, the precipitation hardening, substructure of matrix and index of matrix lattice defects. In this paper the results of investigations 13CrMo4-5 steel was shown. The material for research was taken from thermal power plant elements. Material A was after 150.000 hours of work as the pressure chamber in which was the temperature 530-580oC and the pressure was 12 MPa. Material B was after 250.000 hours of work as the pipeline of superheated steam. The temperature in this case was 530oC but the pressure was 12 MPa as well. The mechanical properties after long time service and changes in fine structure were tested. Parameters of carbide phase electrochemical separation in electrolytes solutions are presented in this work. The most relevant electrolyte and the far better conditions of extraction process were chosen taking into consideration the time needed to get considerable amount of carbide phase constituents. The identification of carbide phases was the special goal of this work. Identification of electrochemically separated carbide phases by means of the XRD analysis was used.

14

The Reciprocal CuInSe2+2CdTe⇔CuInTe2+2CdSe System

Lavrynyuk Z. V., Zmiy O. F., Parasyuk O. V., Olekseyuk I. D., Pekhnyo V. I.

Polish Journal of Chemistry

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2009

|

Vol. 83, nr 1

7-18

EN

Investigation of the reciprocal system CuInSe2+2CdTeUCuInTe2+2CdSe was performed using XRD and differential thermal analysis. The isothermal section at 870 K, the liquidus surface projection, several vertical sections and a spatial diagram were constructed. The existence of a large homogeneity region of the sphalerite modifications of the compounds was established.

15

Zastosowanie dyfrakcji rentgenowskiej do oceny zużycia materiału pobranego z elementów kotła parowego

Lisak J.

Czasopismo Techniczne. Mechanika

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2009

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R. 106, z. 2-M

129-135

PL

Skład fazowy wydzieleń węglikowych obserwowanych w stalach typu 15HM po długotrwałej eksploatacji zależy głównie od czasu i temperatury wygrzewania. Wraz ze zmianami następują zmiany własności użytkowych tych stali. Dlatego badając ten parametr, można wnioskować o stopniu zużycia materiału. Zastosowanie rentgenowskiej analizy dyfrakcyjnej do badań składu fazowego wydzieleń węglikowych w stalach używanych w energetyce na elementy kotła parowego pozwoliło na precyzyjne określenie różnic w składzie fazowym faz węglikowych pojawiających się po kilku wariantach wyżarzania. Warunkiem właściwego przebiegu procesu identyfikacji fazowej jest wyizolowanie faz węglikowych z osnowy metalicznej tak, aby nie doszło do ich rozpadu.

EN

The results of the investigation 15HM steel after 250 000 hours of work as the pressure chamber in thermal power plant was shown. Phase composition of the carbides in 15HM type steels after long-time work is mainly time and temperature-dependent of the soaking. All changes in the phase composition induce the decrease in working properties. The XRD analysis was used to identification of phase carbides. This methods were successful for the differences in phase composition identification. The only one condition is to isolate carbide phases without the destruction.

16

The effect of different starting materials on the synthesis of lithium triborate

Depci T., Ozbayoglu G., Yilmaz A.

Physicochemical Problems of Mineral Processing

|

2007

|

Vol. 41

101-105

EN

Lithium triborate (LiB3O5) was synthesized using different starting materials. The effect of these materials on the phase purity of LiB3O5 was investigated in each case. Identification and characterizations of the products were carried out by powder X-ray diffraction (XRD) and infrared (IR) analyses. The present study showed that the starting materials play an important role in the synthesis of lithium triborate with respect to phase impurity.

PL

Syntezowano trójboran litu (LiB3Os) stosując różne materiały wyjściowe. Badano wpływ tych materiałów na końcową czystość LiB3O5. Identyfikowano i charakteryzowano produkty syntezy za pomocą dyfrakcji rentgenowskiej (XRD) oraz analizy spektroskopowej w podczerwieni (IR). Badania wykazały, że wyjściowe materiały grają ważna rolę w czystości syntezowanego trójboranu litu.

17

Microstructure Transition in Electroplated CU Films at Room Temperature - I. Electrical Resistivity and XRD Analysis

Freundlich P.

Zeszyty Naukowe. Mechanika / Politechnika Opolska

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2003

|

z. 76

75-82

EN

A suite of systematic experimental studies on electroplated copper films was carried out by a systematic change of plating current density and additive concentration in the plating electrolyte. The films were characterized by employing resistivity measurement and x-ray diffraction. In the indicated range, the annealing time decreased with increasing plating current density, and showed a minimum as a function of additive concentration. Electroplated copper films had strong (111) texture which further increased during self-annealing.

18

Materiały kompozytowe o osnowie polimerowej wzmacniane cząstkami magnetycznie twardymi Nd-Fe-B

Dobrzański L.A., Drak M.

Inżynieria Materiałowa

|

2003

|

R. XXIV, nr 6

593-596

PL

W pracy przedstawiono wyniki badań materiału kompozytowego magnetycznie twardego o osnowie polimerowej wzmacnianego cząstkami ze sproszkowanej szybkochłodzonej taśmy Nd-Fe-B. Proszek Nd-Fe-B domieszkowano (10% masowo) proszkami żelaza, aluminium, odlewniczym stopem miedzi z cyną CuSn10, stalą wysokostopową X2CrNiMo17-12-2 oraz tlenkiem aluminium Al2O3. Jako osnowy użyto żywicę epoksydową (2,5% masowo). Kompozyty prasowano jednostronnie jednoosiowo w temperaturze otoczenia pod ciśnieniem 800-900 MPa i utwardzono w temperaturze 180 stopni Celsjusza przez dwie godziny. Zbadano wpływ materiału domieszki na własności magnetyczne i mechaniczne oraz strukturę otrzymanych kompozytów. Przedstawiono wyniki badań rentgenowskiej analizy fazowej. Wyniki badań własności magnetycznych wskazują na ich zróżnicowanie w zależności od zastosowanego materiału domieszki. Materiał magnetycznie miękki, proszek żelaza, zmniejsza w niewielkim stopniu remanencję i wyraźnie obniża koercję HcB. Domieszki materiałów niemagnetycznych zmniejszają zarówno remanencję jak i koercję HcB. Stwierdzono równomierne rozłożenie proszku Nd-Fe-B w osnowie polimerowej, ziarna mają kształt nieregularny, są wydłużone w jednym kierunku i układają się równolegle do siebie większymi płaszczyznami prostopadle do kierunku prasowania. Domieszki rozłożone są w kompozycie w sposób nierównomierny, zaobserwowano skupiska proszków żelaza, aluminium i stopu CuSn10. Wykonano badania wytrzymałości na ściskanie. Stwierdzono, że wszystkie domieszki z wyjątkiem proszku tlenku aluminium podnoszą wytrzymałość na ściskanie. Rentgenowska analiza fazowa umożliwiła identyfikacje fazy magnetycznie twardej Nd2Fe14B.

EN

Investigation results of the polymer matrix hard magnetic composite materials with particles of the powered rapid quenched Nd-Fe-B strip are presented in this paper. The Nd-Fe-B powder was doped (10% wt.) with powders of iron, aluminium, CuSn10 casting cooper alloy with tin, high alloy steel X2CrNiMo17-12-2 and aluminium oxide. Epoxy resin has been used as a matrix (2,5% wt.). The composites were unilaterally and uniaxially pressed at room temperature under the pressure of 800-900 MPa and curved afterwards for 2 hours at 180 degrees centigrade. The influence of dopes' materials kind on magnetic and mechanical properties of composite materials was estimated. Metallographic examination of the composite materials' structure and XRD analysis has been made. Investigations of magnetic properties of composite materials show the influence of the addition material. It was estimated that dopes of soft magnetic material decrease coercive force HcB and slightly reduce remance Br of composite. The addition of non-magnetic material decreases coercive force HcB and reduces remanence Br. Metallographic examination of the structure shows uniform distribution of Nd-Fe-B powder in the polymer matrix, grains are irregular elongated in one direction. Dopes' distribution in a polymer matrix is irregular, agglomerations of powders of aluminium, iron and cooper casting alloy with tin have been noticed. Ultimate compressive strength of composite materials is improved for all the addition material, except powder of aluminium oxide. XRD analysis has identified the hard magnetic phase Nd2Fe14B.

19

Application of XRF and XRD methods for fast analysis of fused iron catalyst for ammonia synthesis

Szczuko D., Arabczyk W.

Chemia Analityczna

|

2000

|

Vol. 45, No. 2

273-280

EN

A fast method for the determination of chemical composition of fused iron catalyst for ammonia synthesis was developed. The catalysts with different amount of promoters and with different oxidation state of iron were examined. The chemical composition of catalysts was determined using XRF, XRD, ICP spectroscopy, flame photometry and man-ganometric titration. Calibration curves for CaO, Al(2)O(3) and K(2)O were plotted. Using XRD method the dependence of the relative Fe(200) and Fe(3)O(4)(400) peak intensity ratio on iron oxidation state was plotted. This dependence, however was different for magnetite and for wustite catalysts. Using this method for catalysts containing cobalt the total amount of cobalt and iron with second oxidation state was determined.

PL

Opracowano szybką metodę określania składu chemicznego stopowego katalizatora żelazowego do syntezy amoniaku. Zbadano katalizatory o różnym składzie i stopniu utlenienia. Przy użyciu metod takich jak XRF, XRD, spektroskopia ICP, fotometria płomieniowa i manganometria określono ich skład chemiczny. Wykreślono krzywe kalibracji dla CaO, Al(2)O(3) i K(2)O. Stosując dyfrakcję promieni rentgenowskich wykreślono zależność stosunku intensywności pików Fe(200) i Fe(3)O(4)(400) od stopnia utlenienia żelaza. Stwierdzono, że ta sama zależność nie może być zastosowana jednocześnie dla katalizatorów konwencjonalnych i wustytowych. Stosując tą metodę dla katalizatorów zawierających kobalt określono ilość kobaltu i żelaza na drugim stopniu utlenienia.