Wyniki wyszukiwania - BazTech

1

Badania wiązania mocznika w procesie otrzymywania nawozów mocznikowo-superfosfatowych

Sadłowski M., Grzmil B., Lubkowski K.

Przemysł Chemiczny

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2016

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T. 95, nr 1

114--117

PL

Badano zdolność mocznika do tworzenia połączeń addycyjnych ze składnikami pulp superfosfatowych, takimi jak CaSO4 nH2O (gdzie n = 0–2) i Ca(H2PO4)2⋅H22O. Reakcje prowadzono ucierając wysuszony nawóz superfosfatowy z mocznikiem w młynie moździerzowym lub dodając mocznik do reaktora rozkładu fosforytu kwasami (H2SO4 lub H3PO4). Skład fazowy produktów badano metodą dyfrakcji rentgenowskiej. Stwierdzono, że najłatwiej przebiega reakcja mocznika z Ca(H2PO4)2⋅H2O, a w dalszej kolejności z CaSO4⋅2H2O i CaSO4⋅0,5H2O. W żadnym z prowadzonych doświadczeń nie zaobserwowano reaktywności mocznika z bezwodnym CaSO4.

EN

Urea additive compds. with superphosphate pulp components (Ca(H2PO4)2⋅H2O and CaSO4⋅nH2O, where n = 0–2), were prepd. The exps. were carried out (i) by milling urea with a dry superphosphate fertilizer in a lab. mortar grinder or (ii) by urea addn. to the reactor after phosphate rock decompn. with H2SO4 or H3PO4. The phase compn. Of products was studied by X-ray powder diffraction method. Ca(H2PO4)2⋅H2O was more reactive than CaSO4⋅2H2O and CaSO4⋅0.5H2O in the urea complexation. The reactivity of anhyd. CaSO4 towards urea was not obsd. in any expt.

2

Zastosowanie nieniszczących dyfrakcyjnych metod rentgenowskich do charakteryzowania stanu struktury materiałów

Skrzypek S. J., Witkowska M., Kowalska M., Chruściel K.

Hutnik, Wiadomości Hutnicze

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2012

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Vol. 79, nr 4

238--246

PL

Artykuł przedstawia niektóre istotne zastosowania metod rentgenowskich do określania wybranych właściwości i charakterystyk materiałowych odnoszących się do struktury i stanu materiałów po różnych etapach procesu wytwarzania i obróbki. Te nieniszczące metody, które wykorzystują dyfrakcję promieni rentgenowskich, dają w pośredni sposób możliwość ujawniania szeregu danych dotyczących struktury wewnętrznej, jak również pomiaru niektórych podstawowych właściwości materiałów. Typowe zastosowania obejmują pomiary mikroi makro-naprężeń własnych, grubości cienkich warstw i powłok, składu fazowego, gęstości defektów struktury, rozmiaru krystalitów oraz ich rozkładu orientacji (tekstury) itp. Prezentowane metody i techniki rentgenowskie wykorzystują szeroki zakres stosowanych długości fali oraz różne warianty geometrii dyfrakcji. W artykule uwzględniono zwłaszcza metody dyfrakcji promieniowania X w geometrii stałego kąta padania (SKP) oraz metodę Bragg-Brentano (BB) stosowane do praktycznego pomiaru grubości powłok i cienkich warstw. Takie nieniszczące pomiary mają aspekt praktyczny, np. w zastosowaniu do kontroli jakości produkcji lub poszczególnych operacji technologicznych, a także do diagnozowania stopnia zużycia eksploatacyjnego elementów maszyn.

EN

The paper presents some important applications of X-ray methods in determination of selected material features and characteristics related to the structure and state of materials after different stages of manufacturing and processing. These non-destructive methods, which base on diffraction of X-rays, give ability to reveal indirectly a number of details of internal structure and to measure some important materials features. Typical applications comprise measurements of micro- and macro- residual stresses, thickness of thin layers and coatings, phase composition, density of lattice defects, size of crystallites and their orientation distribution (texture), etc. The presented X-ray methods and techniques utilize wide range of applicable wavelengths and different variants of diffraction geometry. Especially symmetrical and asym-- metrical Bragg-Brentano method, the methods with grazing incidence angle and reflectivity in different conditions were considered in the paper. In particular the last two methods are destined to thickness measurements of micro- and nano- thin layers and surface coatings. Such X-ray non-destructive methods are recommended for practical applications in quality control of production as well as verification of exploitative and operational wear of machine elements.

3

X-Ray Diffraction Measurements for Riveted Joints. The Application of a Novel Methodology

Gadalińska E., Kaniowski J.

Fatigue of Aircraft Structures

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2012

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Iss. 4

17--28

EN

The X-ray diffraction method is the best, widely available, non-destructive measurement method used to determine the residual and load stresses in crystalline materials. This method can be applied without any limitations to flat specimens. Depending on the equipment geometry, the type of material and geometry of the specimen, there are many limitations, restrictions and recommendations which have to be fulfilled to obtain reliable results. This was the reason for working out a methodology for X-ray diffraction stress measurements for riveted specimens.The first case to analyze is the necessity of choosing an X-ray tube suitable for the specimen material which will give the diffraction peaks in the range of 2Θ angles between 120° and 180°. Afterwards it is crucial to make the best selection of Bragg's angle 2Θ. In the vast majority of cases the best selection is the possibly biggest 2Θ angle because of the best accuracy of the measurement. However, for example for aluminum alloys (for CrKα radiation), this choice is not so obvious. It is much more convenient to perform measurements not for the highest diffraction angle. The best selection in this case is 2Θ=139,3°, and not 156,7°. Other selections which are necessary to be made before measurements are the collimator diameter, time of exposure, ψ tilts and φ oscillations. The proper selection of these parameters is crucial for the fast and efficient performing of measurements and for obtaining reliable results. Before performing the measurement, especially in the case of the specimen with complicated geometry (for example in the case of riveted specimens made of aluminum alloys), it is necessary to analyze the results obtained paying special attention to the possibility of the appearing of the rivet head/driven rivet head shadow during the measurement. The work describes differences between the X-ray stress measurement results obtained without any interference and the results received after eliminating the selected diffraction peaks for which the shadow of rivet head/driven rivet head has appeared.

4

Zmiany poziomu naprężeń własnych w stemplach do wyciskania przeciwbieżnego wyrobów z cynku

Samolczyk J.

Obróbka Plastyczna Metali

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2011

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T. 22, nr 4

255-268

PL

W artykule przedstawiono wyniki badań naprężeń własnych w warstwie powierzchniowej stempli do wyciskania przeciwbieżnego wyrobów z cynku. Pomiarów naprężeń dokonano rentgenowską metodą sin 2, która okazała się przydatną do wyznaczania naprężeń własnych w stemplach do wyciskania przeciwbieżnego metali. W przypadku stempli do wyciskania przeciwbieżnego wyrobów z cynku, czas eksploatacji narzędzi wyraźnie zależy od rodzaju naprężeń panujących w ich warstwie wierzchniej. Naprężenia ściskające przy powierzchni zapewniają bezpieczną eksploatację stempli do wyciskania. Zmiana naprężeń ściskających na naprężenia rozciągające w warstwie wierzchniej powoduje przyspieszenie zużycia narzędzi.

EN

The paper presents the results of investigation of internal stresses in the surface layer of punches for backward extrusion of zinc products. Stress measurements have been effected by the x-ray sin 2 method which proved to be suitable for the determination of internal stresses in punches for backward extrusion of metals. In the case of the punches for backward extrusion of zinc products, the tool exploitation time is clearly dependent on the kind of stresses present in their surface layer. Compressive stresses at the surface result in safe exploitation of extrusion punches. The change of compressive stresses into tensile ones accelerates the tool wear.

5

Influence of heat treatment on changes on structure and magnetic properties of CoSiB alloy

Nowosielski R., Zajdel A., Lesz S., Kostrubiec B., Stokłosa Z.

Journal of Achievements in Materials and Manufacturing Engineering

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2008

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Vol. 27, nr 2

147-150

EN

Purpose: This paper describes influence of heat treatment on changes on structure and magnetic properties of the amorphous Co77Si11.5B11.5 alloy. Design/methodology/approach: The following experimental techniques were used: X-ray diffraction (XRD), static and dynamic measurements of magnetic properties (magnetic balance, fluxmeter, Maxwell-Wien bridge). Findings: The crystallization process involved by heat treatment leads to significant changes of structure and magnetic properties of amorphous Co77Si11.5B11.5 alloy. Research limitations/implications: Practical implications: The attractive properties of Co-Si-B alloy are of special interest for basic research on the materials as well as for their potential applications, like magnetic sensors. According to the results presented in this paper the examined Co77Si11.5B11.5 alloy as a soft magnetic material may be used in noise filters, saturable reactors, miniature inductance elements for abating spike noise, zero-phase current transformers, and magnetic heads etc., i.e. devices which are expected to exhibit high levels of permeability at high frequencies. Originality/value: It has been shown that thermal annealing at temperature close to the crystallization temperature leads to a significant increase of the initial magnetic permeability.

6

Structure and mechanical properties of amorphous Fe84Nb7B9 alloy during crystallisation

Szewieczek D., Tyrlik-Held J., Lesz S.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 24, nr 2

87-90

EN

Purpose: The investigation results of crystallization, in temperature range of 300-700 degrees centigrade in time 1 h, of amorphous Fe84Nb7B9 alloy. The alloy was obtained in tape form by planar-flow-casting method. Design/methodology/approach: The structure was characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) method. The measurement of mechanical properties, like: tensile strength Rm, ductility E and cracking energy Ep, were made. Tensile tests were performed on testing machine INSTRON 1195. Plastic properties of investigated tapes were determined in bending test. Unit cracking energy Ep was evaluated by carrying out the tear test by the use of tensile testing machine INSTRON 1195. Findings: The changes of mechanical properties and fracture morphology being connected with the structure changes involved by crystallization process have been stated. Practical implications: The relationship between heat treatment parameters and mechanical properties can be useful for practical application of these alloys. Originality/value: It has been stated that heat treatment leads to crystallization of two-stage character.

7

Residual stresses in the strips from copper-based alloys

Staszewski M., Rdzawski Z. M., Wrona A.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 25, nr 2

35-38

EN

Purpose: The aim of this work was to define the stress state in the strips from copper-based alloys with an account of the parameters of rolling and flattening. Design/methodology/approach: Samples of thin strips from three commercial copper-based alloys, i.e. CuSn6, CuZn33 and CuNi18Zn27, and from copper 99.98% in purity, were examined. The stress analysis was performed using X-ray diffraction method. The macro-stresses were determined by the measurements of the changes in a lattice constant and by the "square sin psi" technique. The micro-stresses were measured by the diffraction line broadening method. Findings: It was found that the residual stresses, measured at both surfaces of the cold rolled strip, depend strongly on the rolling conditions and on rolling gap geometry. Considerable differences between these surfaces have been observed before and after the flattening process. However, they can be significantly reduced by suitably conducted flattening process. Research limitations/implications: Further studies are necessary to assess the possibility of reducing stresses on both surfaces of a strip in the case of non-ideal shape of rolls in a rolling mill. Practical implications: Modification of technological flowchart for rolling strips from hardly-deformable copper-based alloys enables obtaining the required dead flatness of the strips. Originality/value: The results from this work can be used to improve the technology of rolling and flattening thin strips from copper and copper-based alloys.

8

Influence of crystallisation an amorphous Co77Si11.5B11.5 alloy on corrosion behavior

Nowosielski R., Zajdel A., Baron A., Lesz S.

Journal of Achievements in Materials and Manufacturing Engineering

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2007

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Vol. 20, nr 1-2

167-170

EN

Purpose: This paper describes crystallization kinetics and its influence on changes of electrochemical behavior of amorphous, amorphous relaxed and nanocrystalline Co77Si11,5B11,5 alloy. Design/methodology/approach: The following experimental techniques were used: structural research - X-ray diffraction (XRD) and electrochemical investigations were carried out by means of an electrochemical impedance spectroscopy method. Findings: Heat treatment of amorphous Co77Si11,5B11,5 alloy leads to the formation of the hexagonal alpha-Co phase in an amorphous matrix at the temperature T = 798 K and this is the first stage of the crystallization process. At the temperature T = 873 K appearance of boride phase Co2B, Co3B and silicates phase Co2Si was state. It is the second stage of crystallization. The existence of boride phases was confirmed by after annealing in the temperature range from 730 K up to 873 K. The secondary crystallization is known to cause grain coarsening of phases and the electrochemical properties. The analysis leads to the conclusion that in view of data obtained from electrochemical tests in 3% NaCl solution, the crystallization process begins at lower temperatures than resulting from XRD data Co77Si11,5B11,5 alloy. Practical implications: The attractive properties of Co-Si-B alloy are of special interest for basic research on the materials as well as for their potential applications. Due to their numerous potential application nanocrystalline cobalt based alloys could be work in a wet industrial and marine atmosphere containing sulphide and chloride ions. Electrochemical corrosion can changes structure and magnetic properties of Co-based alloys. Originality/value: It has been shown that thermal annealing at temperature lower than the crystallization temperature leads to a significant changes of the initial electrochemical behaviour in 3% NaCl solution.

9

Crystallization of amorphous Co77Si11.5B11.5 alloy

Nowosielski R., Zajdel A., Lesz S., Kostrubiec B., Stokłosa Z.

Archives of Materials Science and Engineering

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2007

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Vol. 28, nr 3

141-148

EN

Purpose: The investigation results of crystallization of amorphous Co77Si11.5B11.5 alloy in tape form, obtained by melt spinning method during annealing in temperature range 373-873 K with step of 50 K in time 1 h, have been presented in the paper. Design/methodology/approach: The following experimental techniques were used: X-ray diffraction (XRD), electrical resistivity in situ measurements (four-point probe) static and dynamic measurements of magnetic properties (magnetic balance, fluxmeter, Maxwell-Wien bridge). Findings: The changes of magnetic properties connected with the structure changes involved by crystallization process have been investigated of amorphous Co77Si11.5B11.5 alloy. Practical implications: Amorphous magnetic materials have been around for some time and their applications can be found in many types of industrial products. They include transformers, motors, and a wide variety of magnetic components in sensors, power electronics, electrical energy control/management systems, telecommunication equipment and pulse power devices. Originality/value: It has been stated that heat treatment leads to crystallization leads to a significant increase of the initial magnetic permeability.

10

Crystallization kinetics of an amorphous Co77Si11.5B11.5 alloy

Nowosielski R., Zajdel A., Lesz S., Kostrubiec B., Stokłosa Z.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 17, nr 1-2

121--124

EN

Purpose: This paper describes crystallization kinetics and changes magnetic properties involved by process of crystallization Co-Si-B amorphous alloy. Design/methodology/approach: The following experimental techniques were used: X-ray diffraction (XRD), electrical resistivity in situ measurements (four-point probe) static and dynamic measurements of magnetic properties (magnetic balance, fluxmeter, Maxwell-Wien bridge). Findings: In this work has been performed influence of thermal annealing on crystallization kinetics and magnetic properties amorphous Co77Si11.5B11.5 alloy. Practical implications: The attractive properties of Co-Si-B alloy are of special interest for basic research on the materials as well as for their potential applications, like magnetic sensors. The Co soft magnetic material is used in noise filters, saturable reactors, miniature inductance elements for abating spike noise, mains transformers, choke coils, zero-phase current transformers, and magnetic heads etc., i.e., devices which are expected to exhibit high levels of permeability at high frequencies. Originality/value: It has been shown that thermal annealing at temperature close to the crystallization temperature leads to a significant increase of the initial magnetic permeability.

11

Crystallisation kinetics and magnetic properties of a Co-based amorphous alloy

Lesz S., Nowosielski R., Kostrubiec B., Stokłosa Z.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 16, nr 1-2

35--39

EN

Purpose: In the present paper, the kinetics of crystallization process and its correlation with magnetic properties of the Co80Si9B11 alloy was carefully examined. Design/methodology/approach: The following experimental techniques were used: X-ray diffraction (XRD), electrical resistivity in situ measurements (four-point probe), saturation magnetization in situ measurements (magnetic balance) and initial relative magnetic permeability measurements (Maxwell-Wien bridge). Findings: The investigations proved that thermal annealing of amorphous Co80Si9B11 alloy leads to a crystallization process and radical changes of magnetic properties. The activation energy of this process was determined as Ec=3.0±0.2 eV. Research limitations/implications: According to the results presented in the present paper the examined alloys can be used as a very good soft magnetic material. Originality/value: The best soft magnetic properties are observed in as quenched state.

12

Naprężenia własne doczołowej spoiny wielościegowej w stali dwufazowej

Skrzypek S. J., Tasak E., Ratuszek W.

Inżynieria Materiałowa

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2003

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R. XXIV, nr 6

761-763

PL

Pomiar mikronaprężeń własnych metodami dyfrakcyjnymi opiera się na obliczaniu rzeczywistych odkształceń sprężystych sieci krystalicznej poszczególnych faz tworzywa krystalicznego. Metody te są jedynymi, które umżliwiają pomiary naprężeń w każdym składniku fazowym materiału. Można nimi mierzyć wszystkie składowe tensora (naprężeń własnych (NW) w dowolnie zorientowanych współrzędnych umiejscowionych na powierzchni przedmiotu. Metody dyfrakcyjne są nieniszczące, a nawet można je określić jako metody bezkontaktowe. Klasyczną metodykę dyfrakcyjną sin kwadrat Psi zastosowano do pomiaru makroskopowych NW w wybranych miejscach spoiny wykonanej na grubych blachach ze stali dwufazowej. Taka wielościegowa spoina czołowa zawiera zróżnicowane NW, które mieszczą sie w szerokim zakresie naprężeń ściskających i rozciągających.

EN

Residual macrostress measurement by X-ray diffraction methods consist in calculating of elastic strain based on measurement of interplanar dhkl distance for particular phases of solids. These methods enable to measure residual stresses (RS) in any phase compound. Whole components of RS tensor can be established by X-ray diffraction methods. They are non-destructive methods. Traditional square sin Psi X-ray diffraction method was used to establish two components of plane stress tensor in chosen points of weld. This kind of welds performs different level of RS and they are placed in tension and compression ranges.