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EN
Purpose: The paper presents corrosion resistance of composite materials Fe73.5Cu1Nb3Si13.5B9 – PEHD type in sulphuric acid and hydrochloric acid environments. Design/methodology/approach: Composite materials Fe73.5Cu1Nb3Si13.5B9 – PEHD type were manufactured by one-sided uniaxal pressing. The amount of polymer matrix was 2.5%, 5.0%, 7.5%, wt. Powder of the Fe73.5Cu1Nb3Si13.5B9 was made by the high-energy grinding in the shaker type 8000SPEX CertiPrep Mixer/Mill for 1 h, 3 h, 5 h. Composite materials were placed in a corrosive environment and two tests were carried out as specified below: test at the temperature of 25°C, 0.1 M solution of hydrochloric acid HCl, time 348 h; test temperature 25°C, 0.1 M solution of sulphuric acid H2SO4, time 348 h, test temperature 25°C. Findings: Obtained results of corrosion resistance allow to evaluate corrosion wear of composite materials FINEMET (Fe73.5Cu1Nb3Si13.5B9) – PEHD in acidic solutions of 0.1M HCl and 0.1M H2SO4. It was found that the composite materials with 7.5% wt. of polyethylene portion show the best corrosion resistance. Research limitations/implications: Composite materials Fe73.5Cu1Nb3Si13.5B9– PEHD type manufacturing greatly expand the application possibilities of soft magnetic materials nanocrystalline powders however further examination to obtain improved properties of magnetic composite materials and investigations of new machines and devices constructions with these materials elements are still needed. Originality/value: Results allow to complete data concerning composite materials nanocrystalline powder – polymer type which are an attractive alternative for traditional materials with specific magnetic properties. Results are the base for further investigations of the impact of corrosion environment on the magnetic properties such composite materials.
2
Content available remote Modern composite materials manufactured by pressure infiltration method
EN
Purpose: The purpose of this paper is to present the technique of manufacturing the composite materials based on porous ceramic preforms infiltrated by liquid aluminium alloy and examination of the structure and corrosion resistance of those materials. Design/methodology/approach: The material for investigations was manufactured by pressure infiltration method of ceramic porous preforms. The eutectic aluminium alloy EN AC-AlSi12 was use as a matrix while as reinforcement were used ceramic preforms manufactured by sintering of Al₂O₃ Alcoa CL 2500 powder with addition of pore forming agents as carbon fibres Sigrafil C10 M250 UNS manufactured by SGL Carbon Group Company. To determine the corrosion resistance, corrosion test by potentiodynamic method were made consisting in registering the anode polarization curves using the measurements system consisting of the potentiostat PGP-201 working with the Radiometer Copenhagen VoltaMaster 4 software. Findings: The received results show the possibility of obtaining the new composite materials with required structure and corrosion resistance depends of the volume fraction of the reinforcing phase. Practical implications: The composite materials manufactured by the developed method can find application among the others in automotive, aircraft or marine industry as the alternative material for elements fabricated from unreinforced aluminium alloys. Originality/value: The obtained results show the possibility of manufacturing the composite materials by the method of porous sintered framework pressure infiltration based on the ceramic particles, characterized with the better corrosion resistance than aluminium alloy used as the matrix.
3
Content available remote Manufacturing of hard magnetic composite materials Nd-Fe-B
EN
Purpose: This paper presents the material and technological solution which makes it possible obtaining of hard magnetic composite materials: nanocrystalline material-polymer. Design/methodology/approach: For fabrication of composite materials the Nd-Fe-B powder obtained by melt quenching technique was used and for matrix: epoxy resin (EP) or high density polyethylene (HDPE) (2.5 % wt.). Composite materials were compacted by the one-sided uniaxial pressing. The complex relationships among the manufacturing technology of these materials, their microstructure, as well as their properties were evaluated. Materialographic examination of powders morphology and the structure of composite materials were made. Findings: Composite materials show regular distribution of magnetic powder in polymer matrix. Examination of mechanical properties show that these materials have satisfactory compression strength. Research limitations/implications: The advantage of the bonded composite materials is their simple technology, possibility of forming their properties, lowering manufacturing costs because of no costly finishing and lowering of material losses resulting from the possibility of forming any shape. The manufacturing of composite materials greatly expand the applicable possibilities of nanocrystalline powders of magnetically hard materials. Originality/value: Manufacturing processes of hard magnetic composite materials obtaining Nd-Fe-B-polymer matrix.
EN
Purpose: The purpose of the paper is to present corrosion resistance of composite materials Fe73.5Cu1Nb3Si13.5B9 – PEHD type in acid environment. Design/methodology/approach: Composite materials Fe73.5Cu1Nb3Si13.5B9 – PEHD type were manufactured by one-sided uniaxal pressing. Composite materials were placed in a corrosive environment and two tests were carried out as specified below: test at the temperature of 25oC, solution of 0.1 M chloride acid HCl, time of 348h, test at the temperature of 25oC, solution of 0.1 M sulfuric (VI) acid H2SO4, time of 348h. Findings: The main purpose of obtaining this kind of composite materials is broadening possibilities of nanocrystalline magnetic materials application that influence on the miniaturization, simplification and lowering the costs of devices. Practical implications: The manufacturing of composite materials Fe73.5Cu1Nb3Si13.5B9 – PEHD type greatly expand the applicable possibilities of nanocrystalline powders of magnetically soft materials however further examination to obtain improved properties of magnetic composite materials and investigations of constructions of new machines and devices with these materials elements are still needed. Originality/value: Results allow to complete data concerning composite materials nanocrystalline powder – polymer type which are an attractive alternative for traditional materials with specific magnetic properties.
EN
Purpose: The purpose of the paper is to present the material and technological solution which makes it possible obtaining soft and hard magnetic composite materials: nanocrystalline material – polymer. Design/methodology/approach: For fabrication of composite materials the following powders were used: soft magnetic materials (Fe73.5Cu1Nb3Si13.5B9) and hard magnetic material (Nd14.8Fe76Co4.95B4.25) with nanocrystalline structure. Composite materials were bonded by the use of following binder (2.5 % wt.): thermoplastic polyethylene and thermosetting epoxy resin, respectively. Advanced composite materials were compacted by the one-sided uniaxial pressing. Findings: The complex relationships among the manufacturing technology of these materials, their microstructure, as well as their magnetic and mechanical properties were evaluated. The manufacturing of composite materials greatly expand the applicable possibilities of nanocrystalline powders of magnetically hard and soft materials however further examination to obtain improved properties of magnetic composite materials and investigations of constructions of new machines and devices with these materials elements are still needed. Practical implications: Results of investigations of properties and the structure of magnetic composites allow to widen their application possibilities. In manufactured composite materials there is found a good correlation between mechanical and magnetic properties what is very important taking into account the possibility of their application because these composite materials can be used both in stationary devices and in portable ones which are more commonly used. Originality/value: This is an example of simple technology allowing to expand the possibilities of magnetic hard and soft materials.
6
Content available remote Hard magnetic materials Nd-Fe-B/Fe with epoxy resin matrix
EN
Purpose: The purpose of the paper is to present the technological solution of obtaining hard magnetic composite materials based on Nd-Fe-B with addition of iron powder and bounded by epoxy resin. Design/methodology/approach: Composite materials reinforced by Nd-Fe-B particles or Nd-Fe-B with addition of iron powder with polymer matrix were manufactured by one-sided uniaxal pressing. The complex relationships among the manufacturing technology of these materials, their microstructure, as well as their magnetic and mechanical properties were evaluated. Findings: This kind of composite materials can broader the possibilities of application of magnetic materials and reduce the cost of their manufacturing. Practical implications: The manufacturing of hard magnetic composite materials by addition of other powder and bounding them by polymer matrix can greatly extend the applicable possibilities of these materials. There are still made investigations that allow to improve properties of hard magnetic composite materials and influence on the miniaturization of magnets and devices they are used in. Originality/value: The paper shows the technological solution which make it possible obtaining hard magnetic composite materials, their structure and properties.
7
Content available remote Corrosion of Nd-Fe-B permanent magnets
EN
Purpose: purpose of the paper is to presents results of corrosion wear of bonded and sintered hard magnetic materials Nd-Fe-B and magnets covered by protective polymer, lacquer and metal coatings. Design/methodology/approach: Corrosion tests were made in two corrosive environments in water and in 5% NaCl solution. Findings: It was found that the bonded magnets with the polymer matrix demonstrate better corrosion resistance than the sintered magnets. Employment of the protective coatings on the Nd-Fe-B bonded magnets surfaces may feature the effective protection of the substrate material from the corrosive action of the aggressive agent. Practical implications: Magnets covered by protective polymer, lacquer or metal coating are less susceptible to corrosion so employment of these coatings can lower the losses caused by the corrosion of magnets. Corrosion protection of Nd-Fe-B magnets needs further investigations. Originality/value: Analysis of the surface topography of the deposited protective coatings makes it possible to determine coating defects resulting from the action of the aggressive agent. The obtained results can be use in practice to decrease the corrosion wear of these materials.
8
Content available remote Wpływ warunków środowiskowych na starzenie magnesów trwałych Nd-Fe-B
EN
The paper presents results of corrosion wear of bonded and sintered hard magnetic materials Nd-Fe-B and magnets covered by protective polymer, lacquer and metal coatings. Corrosion tests were made in the water and in 5% NaCl solution environment. It was found that the bonded magnets with the polymer matrix demonstrate better corrosion resistance than the sintered magnets. Employment of the protective coatings on the Nd-Fe-B bonded magnets surfaces may feature the effective protection of the substrate material from the corrosive action of the aggressive agent. Analysis of the surface topography of the deposited protective coatings makes it possible to determine coating defects resulting from the action of the aggressive agent. The best protection from the corrosive environment is provided by the polymer coatings. Lower corrosion protection by protective coating was found in the case of sintered magnets. The corrosion damage process of magnets covered with the protective coatings starts in the coating failure location and is connected with the further damage proceeding both into the material and on its surface.
9
Content available remote Materials with specific magnetic properties
EN
Purpose: The purpose of the paper is characterization of properties and application possibilities of modern, soft and hard magnetic materials. Another aspect involved in the paper is to compare these materials with classical magnetic materials and to show their influence on the development of modern technology connected with miniaturization of devices in different branches of techniques. Design/methodology/approach: The main base of the paper is to compare the properties and possibilities of application of soft and hard magnetic materials with taking into consideration the development of manufacturing technology of these materials which by obtaining the maximum possible values of properties allows for simplification of machines and devices construction with use of magnetic elements. Findings: In comparison to classical magnets modern magnetic materials have optimum technology of production with properties that allow for miniaturizing, simplification and lowering the costs of devices. Practical implications: Further examination to obtain improved properties of magnetic materials and investigations of constructions of new machines and devices with these materials elements are still needed. Originality/value: The paper is the review of modern magnetic materials development.
10
Content available remote Kompozytowe materiały magnetycznie twarde Nd-Fe-B o osnowie polimerowej
PL
W pracy przedstawiono charakterystyk magnesów trwałych Nd-Fe-B. Zamieszczono wyniki badań struktury, własności magnetycznych i mechanicznych materiałów kompozytowych magnetycznie twardych oraz omówiono możliwości modyfikacji technologii wytwarzania tych materiałów.
EN
The paper presents characteristic of permanent magnets Nd-Fe-B. Results of examination of the structure, magnetic and mechanical properties of hard magnetic composite materials are shown. The possibilities of manufacturing technology modification are discussed.
PL
W artykule przedstawiono charakterystykę ochronnych powłok polimerowych, lakierowych i metalowych, naniesionych na podłoże z materiału kompozytowego magnetycznie twardego o osnowie polimerowej , wzmacnianego cząstkami Nd-Fe-B z dodatkami proszków metalowych. Strukturę powłok zbadano metodą skaningowej mikroskopii elektronowej. Wykonano także badania twardości, grubości i przyczepności naniesionych powłok.
EN
The paper presents the characterization of protective polymer, varnish and metallic coating deposited onto polymer matrix hard magnetic composite materials reinfoced with Nd-Fe-B particles with metal additions. Structure of coatings was observed in scanning electron microscopy. Thickness, hardness and adhesive of deposited coatings was evaluated.
PL
Zaprezentowano wyniki badań materiałów kompozytowych magnetycznie twardych Nd-Fe-B o osnowie polimerowej wzmacnianych cząstkami Nd-Fe-B z dodatkami proszku aluminium lub odlewniczego stopu miedzi z cyną CuSn1O. Stwierdzono równomierne rozłożenie proszków Nd-Fe-B oraz proszku odlewniczego stopu miedzi z cyną CuSnO w osnowie, natomiast ziarna proszku aluminium tworzą skupiska. Materiały kompozytowe bez dodatków charakteryzują się dobrymi własnościami magnetycznymi. Wprowadzenie dodatków proszków metalowych powoduje wprawdzie obniżenie własności magnetycznych, jednak poprawia własności mechaniczne magnesów oraz podnosi odporność korozyjną materiałów kompozytowych. W pracy przedstawiono także charakterystykę ochronnych powłok polimerowych, lakierowych i metalowych naniesionych na podłoże z materiału kompozytowego magnetycznie twardego z dodatkami proszków aluminium lub CuSnO. Powłoki ochronne na bazie żywic polimerowych są równomiernie nałożone, charakteryzują się zwartą budową bez rozwarstwień i defektów, szczelnie przylegają do podłoża oraz cechują się dobrymi własnościami mechanicznymi, tj. twardością w zakresie 292÷350s (wartość dla szkła - 450s) oraz dobrą przyczepnością do podłoża - 6,4÷8,4 MPa. Powłoki lakierowe wykazują mniejszą szczelność, niższą twardość (]68÷300s) oraz przyczepność do podłoża (5,0÷7,3 MPa). Powłoki metalowe charakteryzują się przyczepnością w zakresie 5,2÷8,4 MPa oraz zwartą budową.
EN
Investigation results of the polymer matrix hard magnetic composite materials with nanostructured particles of the powdered rapid quenched Nd-Fe-B strip with addition of powder of aluminum or CuSn1O casting alloy of cooper with tin are presented at this paper. Metallographic examination of the structure reveals uniform distribution of Nd-Fe-B and CuSnO casting alloy of cooper with tin, however some agglomeration of aluminum powder are observed. The composite material without addition is characteristic of good magnetic properties. Addition of metallic powders decreases magnetic properties of magnets but improves mechanical properties and corrosion resistance of composite materials. The paper presents also the characteristic of the protective polymer, lacquer and metal coatings put down onto the hard magnetic composite materials with addition of powder of aluminum or CuSn1O casting alloy of copper with tin. Protective polymer coating are characteristic of uniform deposition on the entire surface with no visible delamination and defects. Polymer coatings have good mechanical properties: hardness in the range 292÷350s (value for glass 450s) and adhesion 6,4÷8,4 MPa. Lacquer coating are characteristic of lower tightness, lower hardness (168÷300s) and adhesion to the substrate (5,0÷7,3 MPa). Metallic coatings show adhesion of about 5,2÷8,4 MPa and compacted structure.
PL
Przedstawiono wyniki badań odporności korozyjnej materiałów kompozytowych magnetycznie twardych o osnowie polimerowej wzmacnianych cząstkami Nd-Fe-B z szybko chłodzonej taśmy, z dodatkami proszków metalowych: żelaza, aluminium, odlewniczego stopu miedzi z cyną CuSn10 i stali wysokostopowej X2CrNiMo17-12-2, magnesów spiekanych Nd-Fe-B oraz materiałów kompozytowych pokrytych powłokami ochronnymi polimerowymi, lakierowymi i metalowymi. Badania wykonano w środowisku wodnym oraz w 5% roztworze NaCl. Stwierdzono, że większą odpornością na korozję charakteryzują się materiały kompozytowe niż magnesy spiekane. Najlepszą odporność na korozję zapewniają magnesom kompozytowym powłoki polimerowe.
EN
The paper presents the results of corrosion resistance tests of hard magnetic composite materials with polymer matrices reinforced with Nd-Fe-B particles obtained from rapidly cooled tape, with the additions of metal powders of iron, aluminum, CuSn10 casting copper alloy with tin, high-alloy X2CrNiMo17-12-2 steel, sintered Nd-Fe-B magnets and composite materials covered by protective polymer and metal coatings. The corrosion tests were performed in water and in a 5% NaCl solution. It was found that the composite magnets with the polymer matrix demonstrated better corrosion resistance properties than the sintered magnets, whereas the polymer coatings provided the best corrosion protection of composite magnets.
EN
The paper presents a neural network model for evaluation of the rate of corrosive wear of the polymer matrix hard magnetic composite materials with particles of the powdered rapid quenched Nd-Fe-B strip with addition of metallic powder: iron, aluminium, CuSn10 type cast copper-tin alloy and X2CrNiMo17-12-2 high-alloy steel. A neural network model was established based on the research results from the investigations carried out in two corrosive environments. Three types of input data were used in the investigation: the contribution of the added powder, the nominal variable that defined the corrosive environment and the time duration of the test. The percentage corrosive wear of the surface was the output produced from such input data.
PL
W pracy przedstawiono model sieci neuronowej wyznaczania stopnia zużycia korozyjnego materiałów kompozytowych magnetycznie twardych o osnowie polimerowej wzmacnianych cząstkami magnetycznie twardymi Nd-Fe-B z dodatkiem proszku metalowego: żelaza, aluminium, odlewniczego stopu miedzi z cyną CuSn10, stali wysokostopowej X2CrNiMo17-12-2. Na podstawie wyników badań wykonanych w 2 ośrodkach korozyjnych ustalono model sieci neuronowej. Na wejściu przyjęto udział proszku dodatku, zmienną nominalną określającą rodzaj środowiska korozyjnego i czas trwania testu, natomiast na wyjściu wyrażony w procentach stopień zużycia korozyjnego powierzchni.
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.
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