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1

Effect of Fe-Ni substitution in FeNiSiB soft magnetic alloys produced by melt spinning

Kılıçaslan Muhammed Fatih, Yılmaz Yasin, Akgül Bekir, Karataş Hakan, Vurdu Can Doğan

Advances in Materials Science

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2021

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Vol. 21, nr 4(70)

79--89

EN

Alloys of FeNiSiB soft magnetic materials containing variable Fe and Ni contents (wt.%) have been produced by melt spinning method, a kind of rapid solidification technique. The magnetic and structural properties of FeNiSiB alloys with soft magnetic properties were investigated by increasing the Fe ratio. X-ray diffraction analysis and SEM images shows that the produced alloy ribbons generally have an amorphous structure, together with also partially nanocrystalline regions. It was observed that the structure became much more amorphous together with increasing Fe content in the composition. Among the alloy ribbons, the highest saturation magnetization was obtained as 0.6 emu/g in the specimen with 50 wt.% Fe. In addition, the highest Curie temperature was observed in the sample containing 46 wt.% Fe.

2

The Magnetic Entropy Changes in Pb Doped Ni-Mn-Cu-Ga Alloys

Sielicki K., Zygmuntowicz J., Wróblewski R., Leonowicz M.

Archives of Metallurgy and Materials

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2020

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Vol. 65, iss. 2

823--825

EN

Effect of Pb addition on magnetocaloric properties of Ni50 Mn18,75 Cu6,25-aPbaGa25 (a = 1, 2, 3, 4, 5) alloys was investigated experimentally. The magnetic measurements conducted at low field of 4 kA/m showed that addition of Pb led to separation of the both transformation temperatures and significantly shifted the structural transition effect towards lower temperatures as well as increased the Curie temperature. The analysis of isothermal magnetic curves allowed for the calculation of magnetic entropychange (ΔSM). Although the peak values of |ΔSM| for alloys containing 4 and 5 at.% Pb, ~3 J/(kg*K) and ~1.5 J/(kg*K) respectively, are low they stretch over the structural transformation and Curie temperature, and are at least 30 K wide at half maximum height.

3

Approach to ferromagnetic saturation for amorphous Fe-based alloy

Jeż B., Nabiałek M., Jeż K.

Prace Instytutu Metalurgii Żelaza

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2018

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T. 70, nr 3

40--45

EN

The paper presents the results of research on the structure and selected properties of magnetic alloys based on Fe. The alloy with the chemical composition Fe36Co36Y8B20 was produced using two methods: forcing and sucking the liquid alloy into a copper mould. The alloy was cast in the form of 10 mm × 5 mm × 0.5 mm tiles. The structure of the obtained alloys was examined using X-ray diffraction. The measured diffractograms are typical for amorphous materials. Using the Faraday magnetic balance, the magnetic saturation polarisation curves as a function of temperature were recorded. The Curie temperature of the created alloys, which amounted to approximately 750 K, was determined on the basis of numerical analysis. The original magnetisation curves and static magnetic hysteresis loops were measured using a vibration magnetometer. The produced alloys had a saturation magnetisation of about 1.1T and a coercive field value of about 200 A/m. The curves of primary magnetisation were analysed using H. Kronmüller’s theory. It was found that the magnetising process in the area called the ‘approach to ferromagnetic saturation’ is related to the rotation of the magnetisation vector around the linear defects of the structure.

PL

W pracy zamieszczono wyniki badań struktury i wybranych właściwości magnetycznych stopów na bazie Fe. Stop o składzie chemicznym Fe36Co36Y8B20 wytworzono dwiema metodami: wtłaczania oraz zasysania ciekłego stopu do miedzianej formy. Stop odlewano w postaci płytek o wymiarach 10 mm × 5 mm × 0,5 mm. Strukturę otrzymanych stopów badano przy użyciu dyfrakcji rentgenowskiej. Zmierzone dyfraktogramy są typowe jak dla materiałów amorficznych. Przy użyciu wagi magnetycznej Faraday’a zarejestrowano krzywe magnetycznej polaryzacji nasycenia w funkcji temperatury. Na podstawie analizy numerycznej krzywych wyznaczono temperaturę Curie wytworzonych stopów, która wyniosła około 750 K. Przy użyciu magnetometru wibracyjnego zmierzono pierwotne krzywe magnesowania oraz statyczne pętle histerezy magnetycznej. Wytworzone stopy posiadały magnetyzację nasycenia około 1,1T oraz wartość pola koercji około 200 A/m. Wykorzystując teorię H. Kronmüllera, przeprowadzono analizę krzywych pierwotnego magnesowania. Stwierdzono, że proces magnesowania w obszarze zwanym podejściem do ferromagnetycznego nasycenia związany jest z obrotem wektora magnetyzacji wokół liniowych defektów struktury.

4

Magnetic properties of ZnO:Co layers obtained by pulsed laser deposition method

Stefaniuk I., Cieniek B., Rogalska I., Virt I. S., Kościak A.

Materials Science Poland

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2018

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Vol. 36, No. 3

439--444

EN

We have studied magnetic properties of zinc oxide (ZnO) composite doped with Co ions. The samples were obtained by pulsed laser deposition (PLD) method. Electron magnetic resonance (EMR) measurements were carried out and temperature dependence of EMR spectra was obtained. Analysis of temperature dependence of the integral intensity of EMR spectra was carried out using Curie-Weiss law. Reciprocal of susceptibility of an antiferromagnetic (AFM) material shows a discontinuity at the Néel temperature and extrapolation of the linear portion to negative Curie temperature. The results of temperature dependence of EMR spectra for the ZnO:Co sample and linear extrapolation to the Curie-Weiss law indicated the AFM interaction between Co ions characterized by the Néel temperatures TN = 50 K and TN = 160 K for various samples. The obtained g-factor is similar to g-factors of nanocrystals presented in literature, and the results confirm that in the core of these nanocrystals Co was incorporated as Co2+, occupying Zn2+ sites in wurtzite structure of ZnO.

5

Effect of Selected Alloying Elements on the Soft-Magnetic and Mechanical Properties of Injection-Cast Fe61Co10Y8Me1B20 Alloys (Me = Nb, W or Mo)

Pietrusiewicz P., Nabiałek M.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 1

61--64

EN

Properties of amorphous alloys differ from each other when they are produced at different cooling rates and from different chemical compositions. This paper presents studies of the magnetic and mechanical properties of Fe61Co10 Y8 Nb1 B20, Fe61 Co10 Y8 -W1 B20 and Fe61 Co10 Y8 Mo1 B20 alloys, in the form of plates, produced by the injection of liquid alloy into a copper mould. Based on the performed studies, it was found that the substitution of 1% non-magnetic additive into the alloy composition had little effect, as regards the values of saturation magnetization (Ms ) and Curie temperature (Tc ). However, in the case of the coercive field, the sample with the W addition had a value almost half that of the other two alloys. For all of the studied alloys, the microhardness was about 1180 μHv100, i.e. significantly higher than for the same materials in the crystalline state.

6

Microstructure and Soft Magnetic Properties of Fe-Zr-(Pt)-Nb-Cu-B Amorphous Alloys

Gondro J., Błoch K., Nabiałek M., Walters S.

Archives of Metallurgy and Materials

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2017

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Vol. 62, iss. 2A

707--710

EN

This paper presents the results of investigations into the microstructure and magnetic properties of Fe86Zr7Nb1Cu1B5, Fe82Zr7Nb2Cu1B8 and Fe81Pt5Zr7Nb1Cu1B5 alloys. The alloys were investigated in their as-quenched state, in the form of thin ribbons with approximate dimensions as follows: width 3 mm and thickness 20 μm. The investigations were performed utilizing Mössbauer spectrometry and X-ray diffractometry. Also, an evaluation of the low-field magnetic susceptibility and measurements of the magnetization versus temperature and magnetizing field were performed.

7

Curie Temperature and Microstructural Changes Due to the Heating Treatment of Magnetic Amorphous Materials

Gondro J., Błoch K., Brągiel P., Nabiałek M., Szota M.

Archives of Metallurgy and Materials

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2016

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Vol. 61, iss. 1

451--456

EN

Three distinct alloys: Fe86Zr7Nb1Cu1B5, Fe82Zr7Nb2Cu1B8, and Fe81Pt5Zr7Nb1Cu1B5 were characterized both magnetically and structurally. The samples, obtained with spinning roller method as a ribbons 3 mm in width and 20 μm thick, were investigated as-quenched and after each step of a multi steps heating treatment procedure. Each sample was annealed at four steps, fifteen minutes at every temperature, starting from 573K+600K up to +700K depending on type of alloy. Mössbauer spectroscopy data and transmission electron microscope (HRE M) pictures confirmed that the as-quenched samples are fully amorphous. This is not changed after the first stages of treatment heating leads to a reduction of free volumes. The heating treatment has a great influence on the magnetic susceptibilities. The treatment up to 600K improves soft magnetic properties: an χ increase was observed, from about 400 to almost 1000 for the samples of alloys without Pt, and from about 200 to 450 at maximum, for the Fe81Pt5Zr7Nb1Cu1B5. Further heating, at more elevated temperatures, leads to magnetic hardening of the samples. Curie temperatures, established from the location of Hopkinson’s maxima on the χ(T) curve are in very good agreement with those obtained from the data of specific magnetization, σ(T), measured in a field of 0.75T. As a critical parameter β was chosen to be equal 0.36 for these calculations, it confirmed that the alloys may be considered as ferromagnetic of Heisenberg type. Heating treatment resulted in decreasing of TC. These changes are within a range of several K.

8

Hyperfine interaction and some thermomagnetic properties of amorphous and partially crystallized Fe70−xMxMo5Cr4Nb6B15 (M = Co or Ni, x = 0 or 10) alloys

Rzącki J., Świerczek J., Hasiak M., Olszewski J., Zbroszczyk J., Ciurzyńska W.

Nukleonika

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2015

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Vol. 60, No. 1

121--126

EN

As revealed by Mössbauer spectroscopy, replacement of 10 at.% of iron in the amorphous Fe70Mo5Cr4Nb6B15 alloy by cobalt or nickel has no effect on the magnetic structure in the vicinity of room temperature, although the Curie point moves from 190 K towards ambient one. In the early stages of crystallization, the paramagnetic crystalline Cr12Fe36Mo10 phase appears before α-Fe or α-FeCo are formed, as is confi rmed by X-ray diffractometry and transmission electron microscopy. Creation of the crystalline Cr12Fe36Mo10 phase is accompanied by the amorphous ferromagnetic phase formation at the expense of amorphous paramagnetic one.

9

Effects of Co, Ni, and Cr addition on microstructure and magnetic properties of amorphous and nanocrystalline Fe86−xMxZr7Nb2Cu1B4 (M = Co, Ni, CoCr, and Cr, x = 0 or 6) alloys

Łukiewska A., Świerczek J., Hasiak M., Olszewski J., Zbroszczyk J., Gębara P., Ciurzyńska W.

Nukleonika

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2015

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Vol. 60, No. 1

103--108

EN

Mössbauer spectra and thermomagnetic curves for the Fe86-xMxZr7Nb2Cu1B4 (M = Co, Ni, CoCr, and Cr, x = 0 or 6) alloys in the as-quenched state and after the accumulative annealing in the temperature range 600–800 K for 10 min are investigated. The parent Fe86Zr7Nb2Cu1B4 amorphous alloy is paramagnetic at room temperature, and substitution of 6 at.% of Fe by Co, Ni, and CoCr changes the magnetic structure – the alloys become ferromagnetic, whereas replacing 6 at.% of Fe with Cr preserves the paramagnetic state. After the heat treatment at 600 K, the decrease of the average hyperfi ne fi eld induction, as compared to the as-quenched state, is observed due to the invar effect. After this annealing, the Curie temperature for all investigated alloys decreases. The accumulative annealing up to 800 K leads to the partial crystallization; α-Fe or α-FeCo grains with diameters in the range of 12–30 nm in the residual amorphous matrix appear.

10

Magnetic properties of bulk amorphous Fe61Co10Ti3Y6B20 alloy near the Curie temperature

Błoch K.

Journal of Achievements in Materials and Manufacturing Engineering

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2015

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Vol. 73, nr 2

80--85

EN

Purpose: The aim of this study was to conduct studies of the magnetic properties for a massive amorphous alloy Fe61Co10Ti3Y6B20. Design/methodology/approach: The investigated samples were prepared in the form of rods by using the suction-casting method. The material structures were investigated using X-ray. The magnetic properties were studied using a completely automated set up for measuring susceptibility and its disaccommodation. The magnetization as a function of magnetizing field was measured using magnetic Faraday's weight as a part of magnetocaloric effect studies. Findings: In the framework of this study, the structure and magnetic properties of the solid amorphous alloy Fe61Co10Ti3Y6B20 was examined. On the basis of the of X-ray diffraction obtained material was found to be amorphous alloy. Magnetic studies were carried out using a fully computerized system for magnetic susceptibility measures and its disaccommodation. It was showed that both susceptibility curve and isochoric disaccommodation curve maximum occurs in the transition from the state of ferromagnetic material into a paramagnetic state. This peak is called the Hopkinson maximum. From the curves of the magnetic susceptibility as a function of the temperature the value of the Curie temperature was established to about 550 K. Using the measurements of magnetisation as a function of magnetic field strength Arrott curves were constructed. The positive slope of the curves demonstrates the fact that the phase transition ferro-para is of the second kind. Using the magnetization curves the change of the magnetic entropy was determined. The biggest change of the magnetic entropy occur near the Curie temperature. Research limitations/implications: Based on studies carried out as part of this work it was found that the magnetic properties of investigated alloy, ie. magnetic susceptibility and its disaccommodation, are showing a clear change near the Curie temperature. Originality/value: The study of magnetic properties and their behavior in the vicinity of the Curie temperature.

11

Struktura elektronowa pasmowa i właściwości ferroelektryczne kryształów grupy TGS

Andriyevskyy B., Patryn A., Kurlyak V., Romanyuk M., Stadnyk V.

Zeszyty Naukowe Wydziału Elektroniki i Informatyki Politechniki Koszalińskiej

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2014

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Nr 6

5--14

PL

Wykonano porównawcze badania struktur elektronowych pasmowych ferroelektrycznych kryształów siarczanu trójglicyny (TriGlycine Sulfate, TGS), (CH2NH2COOH)3⋅H2SO4, selenianu trójglicyny (TriGlycine Selenate, TGSe), (CH2NH2COOH)3⋅H2SeO4, oraz fluoroberylanu trójglicyny (TriGlycine FluoroBeryllate, TGFB), (CH2NH2COOH)3⋅H2BeF4. Odpowiednie obliczenia z pierwszych zasad (ab initio) przeprowadzono w ramach teorii funkcjonału gęstości z uwzględnieniem międzyatomowych oddziaływań dyspersyjnych. Zastosowana metoda pozwoliła na otrzymanie wyników, lepiej pokrywających się z badaniami doświadczalnymi. Po raz pierwszy została zaobserwowana korelacja obliczonej energii całkowitej i temperatury Curie kryształów TGS, TGSe i TGFB.

EN

Comparative studies of the electronic band structures of the ferroelectric crystals triglycine sulfate (TGS) (CH2NH2COOH)3⋅H2SO4, triglycine selenate (TGSe) (CH2NH2COOH)3⋅H2SeO4 and triglycine fluoroberyllate (TGFB) (CH2NH2COOH)3⋅H2BeF4 have been performed. The respective ab initio calculations have been carried out in the framework of the density functional theory (DFT) with taking into account the interatomic dispersion interactions. The method applied has permitted to obtain results which agree better with corresponding experimental studies. The correlation of the calculated total energy and the Curie temperature for TGS, TGSe and TGFB has been detected for the first time.

12

EPR study of ZnO:Co thin films grown by the PLD method

Cieniek B., Stefaniuk I., Virt I.

Nukleonika

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2013

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Vol. 58, No. 3

359--363

EN

We have studied magnetic properties of zinc-oxide composite doped with a relatively high concentration (4%) of Co ions. Samples were obtained by the pulsed laser deposition (PLD) method with different parameters of the laser ablation. For various samples, the power of laser was changed as well as the temperature of sample heating. Electron paramagnetic resonance (EPR) measurements were carried out and temperature dependence of the EPR spectra was obtained. Analysis of the temperature dependences of the integral intensity of EPR spectra was carried out using the Curie-Weiss law. Fitting yields the following values θCW = 150 K and C = 1.6710, where C is the Curie constant, and θCW is the paramagnetic Curie temperature.

13

Preparation, Magnetic Studies and Band Structure Calculation of NiFe2O4 Nanoparticles

Nabiyouni G., Fesharaki M., Zolotovsky A.

TASK Quarterly : scientific bulletin of Academic Computer Centre in Gdansk

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2011

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Vol. 15, No 1

107-119

EN

We have undertaken a comprehensive theoretical study of the band structure, density of states, dependence of the Curie point and saturation magnetization on the size of NiFe2O4 nanoparticles prepared by the conventional ceramic method. Commercially available NiFe2O4 powder was first annealed in an oxygen environment in a furnace at 1100oC for 3h. The X-ray diffraction pattern indicated that the sample was single-phase at this stage. The average grain size estimated by scanning electron microscopy (SEM) was in the range of 300 to 350nm. The magnetic behavior of the sample at room temperature was studied by means of a superconducting quantum interference device (SQUID). The Curie temperature of the nickel ferrite powder was measured using an LCR meter. The measurement of the Curie temperature and saturation magnetization indicated that a decrease in the grain size leads to a decrease in the Curie temperature and in the saturation magnetization. The small value of saturation magnetization was attributed to a spin-glass-like surface layer on the nanocrystalline nickel ferrite with a ferrimagnetically aligned core (H.Nathani and S.Gubbala 2004 J.Mater. Sci. and Engin. B 111 95). Good agreement was obtained between theory and experimental results.

14

Magnetyczne właściwości oraz struktura czteroskładnikowych amorficznych stopów Fe73Co5Y3B19 i Fe73Ti5Y3B19 odlewanych w postaci taśm

Nabiałek M. G.

Informatyka, Automatyka, Pomiary w Gospodarce i Ochronie Środowiska

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2011

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nr 1

21-23

PL

W pracy przedstawiono wyniki badań mikrostruktury oraz właściwości magnetycznych stopów Fe73Me5Y3B19 (gdzie Me = Co lub Ti) w postaci taśm o grubości 30 ?m. Materiał do badań uzyskano stosując technikę ciągłego odlewania płynnego stopu na miedzianym wirującym walcu. Celem badań było określenie wpływu zamiany magnetycznego kobaltu na niemagnetyczny tytan. Wytworzone stopy, jak wskazują wykonane badania są ferromagnetykami wykazującymi tak zwane miękkie właściwości magnetyczne. Stop z dodatkiem tytanu posiadał strukturę amorficzną, natomiast drugi z badanych stopów jest częściowo skrystalizowany. Magnetyzacja nasycenia taśm była względnie wysoka i wynosiła około 1.25 T. Lepszą temperaturową stabilność stanu ferromagnetycznego wykazywał stop częściowo skrystalizowany z dodatkiem magnetycznego kobaltu.

EN

These paper presents the results of investigation of the microstructure and magnetic properties of Fe73Me5Y3B19 (where Me = Co or Ti) alloys in the form of ribbon with a thickness of 30 ?m. The samples were obtained using the technique of continuous casting of a liquid alloy on the rotating copper cylinder. The aim of this study was to determine the effect of 5% substitution in atomic composition of magnetic cobalt for non-magnetic titanium. It was found that, the investigation alloys are ferromagnetic showing the so-called soft magnetic properties. Alloys with the addition of titanium had an amorphous structure, while the second investigated alloys was partially crystallized. Saturation of the magnetization for obtained ribbons was relatively high and equal about to 1.25 T. A better thermal stability of the ferromagnetic state displayed a partially crystallized alloy with the addition of magnetic cobalt.

15

Remarks on the thermal conductivity and heat flow density of the Indian Craton

Maj S.

Acta Geophysica

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2008

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Vol. 56, no. 4

994-999

EN

The virtual or effective thermal conductivity (ETC) of the Indian subcontinental crust model is calculated from geochemical/geothermal data on the mean radiogenic heat production and on the real thermal conductivity (TC) of crystalline rocks of India. This ETC, amounting to about 3.45 W/mźK, is 1.4 time greater than the mean real TC value (about 2.5 W/mźK). This is in good agreement with the empirical relation between the surface heat flow density and the Curie depth for the Indian Craton.

16

The influence of substrate and cap layer on magnetic characteristics of some multilayers

Staniucha I., Urbaniak-Kucharczyk A.

Materials Science Poland

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2007

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Vol. 25, No. 2

371--375

EN

The influence of non-symmetrical boundary conditions, caused by different materials of the substrate and covering, on some properties of the systems consisting of magnetic layers separated by nonmagnetic spacer have been considered. Magnetic properties like spin wave patterns, FMR spectra, Curie temperature, magnetization and spin wave parameter B have been investigated for symmetrical and nonsymmetrical structures like: Cu(111)/(Fe/Cu)n/Fe/Cu/Si(111), vacuum/(Fe/Cu(111))n/Fe/vacuum, vacuum/( Fe/Cu)n/Si(111) and Cu/(Fe/Cu)n/Fe/GaAs, vacuum/(Fe/Cu)n/Fe/GaAs, where n is equal 1 or 2. Influence of roughness on selected characteristics of magnetic systems with non-symmetrical conditions on external surfaces has been also investigated.

17

The influence of the roughness on the Curie temperature and magnetisation in the multilayers

Staniucha A, Urbaniak-Kucharczyk A.

Materials Science Poland

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2006

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Vol. 24, No. 3

701--705

EN

A system of three magnetic (M) layers divided by nonmagnetic (N) spacers is considered. The existence of roughness on the interfaces, described by the model proposed by Bruno and Chappert, leads to a modification of interlayer exchange coupling (IEC). The Curie temperature and magnetisation are calculated using the Green function formalism for the system of layers with Fe standing for M and Cu or Au standing for N. The parameters characterising this system are taken into account for the GaAs substrate. The results obtained show a decreasing Curie temperature with the increasing roughness parameter as compared to the Curie temperature of the sample with an ideal interface. The magnetisation curves are shifted as a result of roughness in the interface region.