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1

Effect of Cooling Rate on the Precipitation Characteristics of Cast Al-Si-Cu Alloy

Okayasu M., Sahara N., Touda M.

Archives of Foundry Engineering

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2021

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Vol. 21, iss. 4

55--60

EN

The influence of the cooling rate on the extent of precipitation hardening of cast aluminum alloy (ADC12) was investigated experimentally. This study explored the cooling rate of the solidification of Cu in the α-Al phase to improve the mechanical properties of ADC12 after an aging process (Cu based precipitation hardening). The solid solution of Cu occurred in the α-Al phases during the casting process at cooling rates exceeding 0.03°C/s. This process was replaced with a solid solution process of T6 treatments. The extent of the solid solution varied depending on the cooling rate; with a higher cooling rate, a more extensive solid solution was formed. For the cast ADC12 alloy made at a high cooling rate, high precipitation hardening occurred after low-temperature heating (at 175°C for 20 h), which improved the mechanical properties of the cast Al alloys. However, the low-temperature heating at the higher temperature for a longer time decreased the hardness due to over aging.

2

Influence of cation order on the dielectric properties of (1 – x)Pb(Sc0.5Nb0.5)O3-xPb(Yb0.5Nb0.5)O3 ceramics

Garbarz-Glos Barbara, Bąk Wojciech, Antonova Maija, Kalvane Anna, Kajtoch Czesław, Dulian Piotr

Materials Science Poland

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2020

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Vol. 38, No. 3

402--406

EN

Ceramic lead niobates and their solid solutions of (1 – x)Pb(Sc0.5Nb0.5)O3-xPb(Yb0.5Nb0.5)O3 were synthesized by solid state reactions from oxides. The structure of investigated samples was characterized by X-ray diffraction (XRD). Dielectric studies of the ceramics were performed by means of broadband dielectric spectroscopy at the temperature ranging from 600 K to 140 K. For all ceramic samples a diffuse phase transition as well as relaxor ferroelectric behavior were observed.

3

Właściwości strukturalne, optyczne i elektryczne TiO2 modyfikowanego Fe2O3

Karoń Iwona, Radecka Marta

Materiały Ceramiczne

|

2019

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T. 71, nr 1

17--24

PL

Celem pracy było określenie własności strukturalnych, elektrycznych i optycznych TiO2 modyfikowanego Fe2O3. Materiały TiO2-Fe2O3 syntezowano metodą zol-żel w zakresie (0-2)% mol. Fe2O3. Badania dyfrakcji promieniowania rentgenowskiego XRD wskazują, że niedomieszkowany TiO2 oraz materiały o zawartości do 0,25% mol. Fe2O3 krystalizują w strukturze rutylu. Przewodnictwo elektryczne mierzono w funkcji składu oraz temperatury (425-700 °C). Położenie i kształt krawędzi absorpcji podstawowej zależy od koncentracji domieszki. Własności strukturalne i elektryczne materiałów potwierdzają zakres tworzenia roztworów stałych.

EN

The aim of this work was to determine the structural, electrical and optical properties of the TiO2 modified with Fe2O3. Fe2O3-TiO2 materials were synthetized by the sol-gel method in the range 0-2 mol% Fe2O3. XRD X-ray diffraction studies indicate that undoped TiO2 and materials with a content of up to 0.25 mol% Fe2O3 crystallize in the rutile structure. Electrical conductivity was measured as a function of composition and temperature (425-700 °C). The location and shape of the primary absorption edge depends on the concentration of the admixture. Structural and electrical properties of materials confirm the range of solid solution formation.

4

Low temperature preparation of stabilized aluminium titanate ultrafine powder assisted by the solvothermal treatment process

Zhang Quan, Liu Jianmin, Jiang Wei-Hui, Feng Guo, Jiang Feng, Wang Tao

Materiały Ceramiczne

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2019

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T. 71, nr 4

362--367

EN

Stabilized aluminium titanate (AT) ultrafine powder with the average particle size of 150 nm was prepared at 1000 °C assisted by the solvothermal process, using aluminium nitrate (Al(NO3)3•9H2O) and titanium tetrachloride (TiCl4) as precursor materials, ethanol as solvent, manganese(II) or iron(III) as stabilizer and PEG1000 as additive. The phase transition process of AT dry gel powder and the influence of technological parameters on the synthesis of stable AT superfine powder were studied by DTA-TG, XRD and TEM. The results showed that the amorphous dry gel formed anatase phase first, and then transformed into Al2(1-x)MgxTi1+xO5 solid solution. Magnesium acetate shows better stabilization effect compared with ferric chloride and ferric sulfate. Optimized dosages of magnesium acetate and PEG1000 are 10 mol% and 3 wt%, respectively.

PL

Stabilizowany, bardzo drobny proszek tytanianu glinu (AT) o średniej wielkości cząstek 150 nm został przygotowany w 1000 ° C przy pomocy procesu solwotermalnego, przy użyciu azotanu glinu (Al(NO3)3•9H2O) i czterochlorku tytanu (TiCl4) jako materiałów prekursorowych, etanolu jako rozpuszczalnika, mangan(II) lub żelazo(III) jako stabilizatorów i PEG1000 jako dodatku. Proces przemiany fazowej suchego proszku żelu AT i wpływ parametrów technologicznych na syntezę stabilnego super drobnego proszku AT zbadano za pomocą DTA-TG, XRD i TEM. Wyniki wykazały, że amorficzny suchy żel najpierw utworzył fazę anatazową, a następnie przekształcił się w stały roztwór Al2(1-x)MgxTi1+xO5. Octan magnezu wykazuje lepszy efekt stabilizujący w porównaniu z chlorkiem żelazowym i siarczanem żelazowym. Zoptymalizowane dawki octanu magnezu i PEG1000 wynoszą odpowiednio 10% mol. i 3% wag.

5

Wady i zalety mieszania „na sucho” zestawu surowcowego niebieskozielonych spinelowych pigmentów ceramicznych z udziałem kobaltu

Dziubak C.

Szkło i Ceramika

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2018

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R. 69, nr 6

6--11

PL

Przedstawiono wyniki badań wybranych właściwości spinelowych pigmentów niebieskich, niebieskozielonych i zielonych o składzie pierwiastkowym Zn-Co-Cr-Al, otrzymanych metodą ceramiczną poprzez mieszanie zestawu surowcowego „na sucho”. Wybór metody podyktowany jest dążeniem do obniżenia kosztów wytwarzania pigmentów celem uatrakcyjnienia ich oferty handlowej. Ponieważ cena surowców w zasadzie nie zależy od producenta pigmentów, zmniejszenia kosztów ich wytwarzania poszukuje się na innych etapach procesu wytwórczego. Jedną z możliwości jest zastąpienie energochłonnego procesu mieszania surowców „na mokro” mieszaniem „na sucho”. Po spełnieniu warunków odpowiedniej wilgotności, uziarnienia i czasu mieszania substratów metoda sprawdziła się w wielu technologiach wytwarzania pigmentów o zróżnicowanych składach surowcowych. W przypadku zestawów z udziałem tlenku kobaltu, który ma specyficzne właściwości fizyczne, warunki mieszania „na sucho” muszą być rozszerzone, co przedstawiono w zamieszczonych wynikach badań.

EN

The report presents the results for selected properties of blue, blue-green and green spinel pigments with the elemental composition Zn-Co-Cr-Al, produced by the ceramic method through dry batch mixing. The choice of the method was dictated by the efforts to reduce the costs of pigment manufacturing, in order to make them commercially more attractive. As the pigment manufacturer has practically no influence on the price of the raw materials, possible cost reductions have to be sought at other stages of the manufacturing process. One of the possibilities is to replace the energy-consuming process of wet mixing of raw materials with dry mixing. Provided that the specific requirements of moisture content, grain size and mixing time are met, the method proves effective in numerous manufacturing technologies of pigments with varied raw material composition. For batches with the addition of cobalt oxide, which displays peculiar physical properties, the requirements for dry mixing conditions must be broadened, as it has been presented in the enclosed study results.

6

Wpływ domieszek kilku metali na właściwości krzemianu trójwapniowego

Jelito E.

Cement Wapno Beton

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2018

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R. 21/83, nr 3

182--194

PL

W pracy przedstawiono wyniki badań wpływu dodatków ZnO, MgO, Al2O3, Cr2O3 i 2% MgO + 2% Al2O3, odpowiadający syntetycznemu alitowi. Największą wytrzymałość miał zaczyn z C3S zawierający cynk, po 28 dniach z dodatkiem 2% ZnO; wynoszącą 101 MPa. Znacznie mniejszą wytrzymałość miały próbki z dodatkiem Al2O3, a najmniejszą miał zaczyn z C3S + 1% Cr2O3. Na drugim miejscu po cynku lokuje się "syntetyczny" alit, który zapewnia dużą wytrzymałość po 1 i 2 dniach, a taką samą jak 3% dodatek ZnO po 7 dniach. Dobrą wytrzymałość daje także dodatek 2% MgO, z wyjątkiem krótkich czasów dojrzewana. Mikrokalorymetria wykazała, że występuje dobra korelacja ciepła hydratacji z wytrzymałością, aczkolwiek nie ma korelacji okresu indukcji, który jest długi w przypadku cynku, natomiast zaczyn C3S + ZnO ma po 1 dniu dużą wytrzymałość. Badania mikrostruktury zaczynów wykazały, że cynk nie jest równomiernie rozmieszczony w kryształach krzemianu trójwapniowego, są kryształy, które w ogóle nie zawierają cynku. Spowodowało to podobne zróżnicowanie w fazie C-S-H; faza ta zawierająca cynk ma nietypową morfologię.

EN

In the paper the experimental results of the influence of ZnO, MgO, Al2O3 Cr2O3 and 2% MgO + 2%Al2O3 addition to C3S, the last one corresponding to synthetic alite, on the properties of these solid solutions are presented. The highest compressive strength had the paste of C3S + ZnO, after 28 days equal to 101 MPa. Significantly lower strength had the specimens with Al2O3 and the lowest the paste of C3S+ 1% Cr2O3. On the second place after zinc was the paste of “synthetic” alite which had the high strength after 1 and 2 days and the same as the sample of C3S + 3% ZnO after 7 days. Good strength the specimens of C3S + 2% MgO are also assuring, with exception of the short period of curing. The microcalorimetry had shown the good correlation of the heat of hydration with strength, however, there was no correlation of the induction period time with early strength of the paste from C3S + ZnO. Simultaneously the observation of the pastes microstructure had shown that zinc is not uniformly distributed among the tricalcium silicate crystals; there are particles which do not contains zinc. The similar differentiation of C-S-H phase was observed; this phase containing zinc has the untypical morphology.

7

Crystal structure and Mössbauer effect in multiferroic 0.5BiFeO3-0.5Pb(Fe0.5Ta0.5)O3 solid solution

Stoch A., Maurin J., Stoch P., Kulawik J., Szwagierczak D.

Nukleonika

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2017

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Vol. 62, No. 2

177--181

EN

Multiferroic 0.5BiFeO3-0.5Pb(Fe0.5Ta0.5)O3 solid solution is a material that exhibits ferroelectric and antiferromagnetic orderings in ambient temperature. The solid solution was obtained as a result of a conventional reaction in a solid state. The obtained material is a dense, fine-grained sinter whose surface was observed by scanning electron microscopy (SEM) and stoichiometry was confirmed by energy dispersive X-ray spectroscopic (EDS) analysis. According to the X-ray powder diffraction (XRD) measurements, the main phase is R3c space group with admixture of Pm-3m regular phase. Small contribution of pyrochlore-like phase was also observed. Mössbauer spectroscopy suggested random distribution of Fe3+/Ta5+ cations in the B sites of ABO3 compound. Reduction of the magnetic hyperfine field with an increase in the substitution of Ta5+ in Fe3+ neighbourhood was also observed.

8

Synthesis and Characterization of Black CoFe2O4 Pigments Using MOOH (M = Fe and Co) Nanorod

Yu R., Yun J., Kim Y.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2B

1231--1234

EN

We studied the coloration and phase transformation of various iron based pigment with cobalt substitution method and heat treatment. First, we synthesized well defined one dimension β-Fe/CoOOH nanorods using the solid solution method. Yellowish β-Fe/CoOOH nanorods were transformed into reddish intermediate states and, finally, black CoFe2 O4 pigments was obtained. Divalent cobalt ions easily occupied tetrahedral sites. The prepared pigments were well characterized in terms of physical properties by using UV-vis, CIE Lab color parameter measurements, SEM (scanning electron microscopy) and XRD (powder X-ray diffraction). In addition, the magnetization property of the prepared CoFe2 O4 pigment was confirmed by VSM (vibrating sample magnetometer).

9

Necessary Thermodynamics Factors to Obtain Simple Solid Solutions in High-Entropy Alloys from the Al-Ti-Co-Ni-Fe System

Górecki K., Bała P., Kozieł T., Cios G.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 4

2141--2145

EN

In this paper findings regarding the design and synthesis of High-Entropy Alloys based on mixing enthalpy, mixing entropy, δ parameter, Ω parameter and valence electron concentration are presented. Four alloys were synthesised with different predicted crystalline structures. Results of the microstructure and crystal structure studies are presented. It was shown that predicted structures as well as complex intermetallic phases exist in the material. The validity of valence electron concentration as well as additional parameters such as mixing enthalpy, mixing entropy and others necessary to obtain only the solid solution in High-Entropy Alloys were examined.

10

Optimization of Selected Parameters of Refractory Solid Solution Formation With Essential Storage and Transport Properties

Śnieżek E., Szczerba J., Prorok R., Jastrzębska I.

Logistyka

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2014

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nr 4

4981--4988, CD6

EN

The work presents (Ca,Sr)ZrO3 solid solution formation which isresistant to hydration and thus having important properties to facilitate storage and transport.The paperraises the issue of effective selection of synthesis parameters. In this case analysis of phase diagrams, also literature data analysis, provide essential information about predicted properties and preparation conditions of matter. On this basis, sampleswere prepared by a solid state reaction. (Ca,Sr)ZrO3 solid solution were obtained during two-step heat treatment at 1200 and 1400°C. X-ray diffraction, Scanning Electron Microscopy and mercury poro-simetry were used to check and examine obtained samples.

PL

Artykuł opisuje proces tworzenia się roztworu stałego, (Ca,Sr)ZrO3 odpornego na hydratację a tym samym posiadającego istotne właściwości ułatwiające magazynowanie i transport. Porusza on zagadnie-nie związane z efektywnym doborem parametrów procesu na bazie analizy diagramów fazowych i danych literaturowych, które pozwalają w pewnym stopniu przewidzieć zastosowanie niezbędnych warunków i potencjalne właściwości otrzymanych substancji. Bazując na tych danych wybrano proces syntezy przebiegającej w fazie stałej. (Ca,Sr)ZrO3otrzymano w wyniku dwustopniowego wypalania w 1200 i 1400°C. Próbki scharakteryzowano metodą XRD, SEM/EDS i porozymetrii rtęciowej.

11

Wpływ obróbki kriogenicznej na procesy wydzieleniowe z przesyconych roztworów stałych na przykładzie martenzytu stali narzędziowej i przesyconego roztworu stałego stopu Al-4,7% Cu

Wierszyłłowski I., Niemczyk W.

Inżynieria Materiałowa

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2010

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Vol. 31, nr 2

137-142

PL

Przedstawiono wyniki badań porównawczych procesów odpuszczania stali narzędziowej po hartowaniu konwencjonalnym oraz po hartowaniu i kriogenicznej obróbce cieplnej. Prezentowano również wyniki badań procesów starzenia stopu Al-4,7% Cu po konwencjonalnej i kriogenicznej obróbce cieplnej. Stwierdzono, że w obu przypadkach obróbka kriogeniczna wpływa na przebieg procesów odpuszczania oraz procesów starzenia. Mechanizmy oddziaływania są w każdym przypadku inne. W stali po obróbce kriogenicznej procesy odpuszczania zaczynają się już podczas dochodzenia od temperatury -196°C do temperatury otoczenia i przyspieszają wzrost twardości spowodowany odpuszczaniem. W stopie Al-Cu po obróbce konwencjonalnej procesy rozpuszczania się wydzieleń i wywołany nimi spadek twardości pojawia się szybciej niż w stopie po obróbce kriogenicznej. Analizowano przyczyny takich zmian na podstawie danych literaturowych.

EN

The paper presents results of comparative studies of tempering processes of quenched and conventionally treated tool steel vs. the same steel quenched and cryo-treated. Also ageing processes of Al-4.7% Cu alloy after conventional and cryo-treatments are analyzed and the results presented. It has been observed that in both cases cryogenic treatment has an effect on the development of the tempering and ageing processes. The mechanisms of the influence are different in each case. In the cryo-treated steel, the tempering processes already begin in the process of reaching ambient temperature from -196°C and accelerate the increase in hardness because of tempering. In conventionally treated Al-Cu alloy the processes of dissolving precipitates and the resulting decrease in hardness occur earlier than in the cryo-treated alloy. Reasons of such changes have been analyzed.

12

Przesycanie grzaniem indukcyjnym stopu aluminium 7075

Sawicki J., Kaczmarek Ł., Staszewski W., Zgraja J., Kędzierski P., Kaszewski R.

Tribologia

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2009

|

nr 6

103-110

PL

Niniejszy artykuł dotyczy badań przesycania stopu aluminium 7075 metodą indukcyjną. Badania prowadzono w specjalnie zaprojektowanej komorze wypełnionej argonem. W pierwszej kolejności zbadano wpływ mocy i czasu na głębokość przesycania warstwy wierzchniej. Następnie przeprowadzono zgniot i próbki poddano starzeniu. Zbadano gradient twardości warstwy wierzchniej oraz przeanalizowano morfologie próbek.

EN

The major objective of this study is to solid solution treatment of 7075 aluminium alloy by induction heating. This study was carried out in an argonium atmosphere chamber. The first step was to analyze the influence of generator power and time on the thickness of solid solution layer. The second step involved cold work of the sample and artificial ageing treatment. Additionally, the morphology and hardness profile was measured.

13

Relaxor phase transition of polycrystalline (Ba0.90Sr0.10)(Ti0.75Sn0.25)O3

Kajtoch C.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

|

Vol. 37, nr 1

44-47

EN

Purpose: The purpose of this work was to determinate the influence of the nonferroactive 25% Sn substitutions in (sublattice B) on changes of the character of phase transition (PT) in comparison with pure barium titanate BaTiO3 (BT). Design/methodology/approach: The dielectrometry method was applied in order to measure complex dielectric permittivity and other dielectric functions of ferroelectric (Ba0.90Sr0.10)(Ti0.75Sn0.25)O3 (BSr10TSn25). Findings: It was affirmed, that 25% substitution of Sn ions changed the type of phase transition. The transition was strongly diffused and typical for relaxor materials. The strong dependence of temperature Tm (peak of the electric permittivity ĺ’) on frequency of the applied electric field was observed. It means, that this material belongs to relaxor type. The polar character of this solution was also observed in a broad temperature range (in the paraelectric phase too). This behaviour is connected with the occurrence of polar regions (clusters). Practical implications: The results can be used in order to describe changes of PT in the relaxor solid solutions with nonferroactive substitutions in sublattice B. Originality/value: Value of this work relies on the experimental examination of the dielectric properties of (BSr10TSn25) solid solution. The temperature of the glassy transition Tf and the activation energy was calculated. The low value of the phase angle is connected with the existence of the polar regions. The dielectric phase transition is connected with change of interactions, of average range, in the system of clusters.

14

Dielectric properties of polycrystalline (Ba0.40Sr0.60)O3

Kajtoch C., Bąk W., Gabryś M., Mroczka K., Starzyk F., Żmija J.

Archives of Materials Science and Engineering

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2009

|

Vol. 40, nr 1

33-36

EN

Purpose: Purpose of this paper is to qualify of the degree and the causes of broadening of the phase transition in the polycrystalline solid solution (Ba0.40Sr0.60)TiO3 (BS60T). Design/methodology/approach: Polycrystalline samples of (Ba0.40Sr0.60)TiO3 (BS60T) were prepared by calcinations method at temperature 1570K. Images of the morphology of the samples were taken by means of electron microscope Philips SEM 525M at room temperature. Dielectric measurements were performed with application of Quatro Cryosystem 4.0 Agilent Precision LRC meter HP4824A equipped with WinDETA 5.62 software Novocontrol. Measurements were taken under cooling with 2K/min speed. Measuring electric field frequency was from the range 20 Hz - 1 MHz. Findings: The dielectrometry was applied to measure complex dielectric permittivity and other dielectric functions of ferroelectric (BS60T). It was affirmed, that 60% substitution of Sr ions changed the type of phase transition. Weak dependence of temperature Tm=208 K (temperature of maximum electric permittivity &epsilon') on frequency of the external electric field testifies about diffused character of the phase transition (DPT). The polar character of this material was also observed in the paraelectric phase (to 360 K). This observation is connected with the occurrence of polar clusters in this phase. Research limitations/implications: Results can be used in order to describe the phase transition modifications in the solid solutions with ferroactive substitutions in sublattice B of the perovskite. Originality/value: Value of this work relies on the experimental examination of the electric properties of BS60T solid solution. The low value of phase angle in the paraelectric phase is connected with the occurrence of the polar regions (clusters).

15

Comparative X-ray investigation of Ni/Cu systems heated in the 250-350 stC temperature range

Gągorowska B., Kucharska B., Duś-Sitek M., Tokarz A.

Materials Science Poland

|

2008

|

Vol. 26, No. 1

149--155

EN

Results of investigation of structural properties of Cu/Ni multilayers have been presented. Samples were obtained by the electrochemical method and after deposition they were heated from 250 oC to 350 oC. The increase of the heating temperature and of the Cu thickness in multilayers caused a decrease of intensities of peaks corresponding to (111) planes. The phenomenon results from the formation of a solid solution in the interfaces. Heating of multilayers in the investigated temperature range resulted in the increase of tensile stresses in external layers and of compressive stresses in substrate adjacent layers.

16

Dielectric properties of polycrystalline (Ba0.60Sr).40)Ti0.8O3

Gabryś M.

Archives of Materials Science and Engineering

|

2008

|

Vol. 34, nr 1

27-30

EN

Purpose: The purpose of the work was to determinate the influence of the ferroactive Sr substitutions in sublattice A and the nonstoichiometry in sublattice B on changes of physical properties and the character of phase transition (PT) in pure barium titanate BaTiO3 (BT). Design/methodology/approach: The polycrystalline samples of (Ba0.60Sr0.40)TiO3 and (Ba0.60Sr0.40)Ti0.8O3 were obtained by the calcinations method in temperature 1620 K. The dielectric measurements were executed by automatic device (QUATRO KRIO 4.0 with LCR Agilent 4824A meter and BDS 1100 cryostat). The materials were investigated under cooling conditions with speed of 2 K/min and within frequency range from 20 Hz to 1 MHz. Findings: The dielectrometry was applied to measure complex dielectric permittivity and other dielectric functions of ferroelectric (Ba0.60Sr0.40)TiO3 (BST-40) and (Ba0.60Sr0.40)Ti0.8O3 (BST-40/0.8). It was affirmed, that 40% substitution of Sr ions as well as 20% deficiency of Ti ions in solid solution reduced temperature and changed the type of phase transformation. The transformation stood strongly diffused. The weak dependence of temperature Tm (peak of electric permittivity ε') from frequency of electric measuring field was observed. It means, that this material should be prescribed to the class of ferroelectrics with diffused phase transformation (DPT). The polar character of this solution was also observed in the paraelectric phase. It is connected with the occurrence of polar clusters in paraelectric phase. Practical implications: Results can be used to construct the model describing changes in the solid solutions with ferroactive and nonferroactive substitutions in sublattice A or B of the perovskite. Originality/value: Value of this work relies on the experimental examination of the electric properties of nonstoichiometric BST-40 solid solution. The low value of phase angle in the paraelectric phase was connected with the occurrence of the polar regions.

17

Structure and properties of precipitation strengthened silver alloys

Gryziecki J., Sobota J.

Archives of Metallurgy and Materials

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2007

|

Vol. 52, iss. 4

665-671

EN

The paper presents the results of investigations of designed and manufactured silver alloys with additions, enabling by way of precipitation strengthening to obtain high strength properties and such additions which have high negative oxidation energy. In the manufactured alloys a high strengthening effect has been obtained as a result of the precipitation of Al4Cu9 phase during the decomposition of supersaturated solid solutions. On the other hand, the alloy additions with high negative oxidation energy formed a self-restoring oxide layer, protecting effectively against atmospheric corrosion. The composition of the obtained properties of the examined alloys guarantees good functional properties of the products made from these alloys as well as high aesthetic assets.

PL

Praca przedstawia wyniki badań nad zaprojektowanymi i wytworzonymi stopami srebra z dodatkami umożliwiającymi drogę umocnienia wydzieleniowego uzyskać wysokie właściwości wytrzymałościowe oraz takimi, które mają dużą ujemną energię utleniania. Osiągnięto w wytworzonych stopach silny efekt umocnieniowy w wyniku wydzielania się fazy Al4Cu9 podczas rozpadu przesyconych roztworów stałych. Natomiast dodatki stopowe o dużej ujemnej energii utleniania utworzyły warstwę tlenkową, samoodnawialną, chroniącą skutecznie przed korozją atmosferyczną. Zespół uzyskanych właściwości badanych stopów zapewnia wytworzonym z nich wyrobom dobre właściwości użytkowe oraz wysokie walory estetyczne.

18

Silver alloys resistant to darkening

Gryziecki J., Sobota J., Włoch G.

Archives of Metallurgy and Materials

|

2007

|

Vol. 52, iss. 1

143-146

EN

The study presents the results of investigation of the resistance to sulfur corrosion and of the mechanical properties of silver alloys without copper, of 925 fineness. As the alloy additions there were used elements which are able to create on the alloy surface an oxide layer as a protection against corrosion and which reduces the SFE of the alloy. The obtained silver alloys without copper, of 925 fineness, are characterized by high resistance to the action of sulfur corrosion and good mechanical properties.

PL

W niniejszej pracy przedstawiono wyniki badań odporności na działanie korozji siarkowej oraz właściwości mechanicznych bezmiedziowych stopów srebra próby 925. Jako dodatki stopowe zastosowano pierwiastki, które mają zdolność do tworzenia na powierzchni stopu warstwy tlenkowej, stanowiącej ochronę przed korozją oraz obniżające EBU stopu. Wytworzone bezmiedziowe stopy srebra próby 925 cechują się bardzo dobrą odpornością na działanie korozji oraz dobrymi właściwościami mechanicznymi.

19

Phase Equilibria in the Cu2S-{Sb,Bi}2S3-Ga2S3 and Cu2S-{Sb,Bi}2S3-In2S3 Systems at 673 K

Olekseyuk I., Zhbankov O., Kumanska Y., Tkachuk V.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 5

817-823

EN

Phase equilibria in the Cu2S-{Sb,Bi}2S3-Ga2S3 and Cu2S-{Sb,Bi}2S3-In2S3 systems at 673 K were investigated by X-ray powder diffraction and their isothermal sections were constructed. No quaternary compounds or continuous solid solutions were found. The homogeneity region of the CuIn5S8 phase in quasibinary Cu2S-In2S3 system was determined in the range 7.3-17.2mol.% Cu2S. The Rietveld refinement of the crystal structure CuGa5S8 has been performed, using powder diffraction pattern in the zinc blende model (SG F43m, a = 0.52246(2) nm).

20

Particular Features of Formation of the Anhydrous Solid Solutions of Mg, Mn(II), Co(II) and Zn Diphosphates

Antraptseva N., Tkachova N., Ponomaryeva I.

Polish Journal of Chemistry

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2006

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Vol. 80, nr 10

1623-1631

EN

The sequence of physical and chemical as well as structural transformations accompanying the formation of solid solutions of anhydrous Mg,Mn(II), Co(II) and Zn diphosphates by thermal dehydration of corresponding hydrated salts was investigated. The interconnection between state of water in crystallohydrate, on one side, and mechanism of its removal, on the other side, was considered. The peculiarities controlling the processes of formation of solid solutions of anhydrous divalent metal diphosphateswere established.