Download it once and read it on your kindle device, pc, phones or tablets. Ni 2 mnal, ni 2 mnin, ni 2 mnsn, ni 2 mnsb, ni 2 mnga. Pdf magnetically driven actuator materials, such as the ternary and intermetallic heusler alloys. Thermoelectric performance of a metastable thinfilm.
Half heusler alloys as promising thermoelectric materials by alexander a. Tetragonal superstructure of the antiskyrmion hosting heusler compound mn1. We investigated the magnetic field h dependence of magnetization m at the curie temperature tc, and at t 4. Heusler alloys properties, growth, applications claudia. Density functional theory calculations suggest that.
Nov 14, 2014 the electronic structure and magnetism of the heusler alloys fe2crx x p, as, sb, bi have been investigated by firstprinciples calculations based on density functional theory. Disorder dependent halfmetallicity in mn 2 cosi inverse. Since the prediction of the half heusler halfmetal nimnsb with 100% spin polarization2,many studies have been devoted to searching for and verifying heuslers with halfmetallicity. A typical example of magnetically controlled shape memory alloys msma is ni. Structure of rapidly quenched ga free heusler alloys. Pdf on mar 1, 2020, qiang gao and others published designing rareearth free permanent magnets in heusler alloys via interstitial doping find, read and cite all the research you need on. Some heusler compounds also exhibit properties of materials known as ferromagnetic shapememory alloys. Avik ghoshs group at the university of virginia, provides information on three families of heusler alloys, full heuslers a2bc, half heuslers abc and inverse heuslers abac. Despite hffree halfheusler hh alloys being currently explored as an important class of costeffective thermoelectric materials for power generation, owing to their thermal stability coupled with high cost of hf, their figureofmerit zt still remains far below unity. Mar 16, 2015 an approach to design compensated ferrimagnetic heusler alloys is established. The most prominent example is the combination of magnetism and exceptional transport properties in spintronic devices. Computational investigation of heusler alloys for spintronic. Structure and magnetic properties of heusler alloy fe niz. Properties, growth, applications springer series in materials science on free shipping on qualified orders.
Magnetically induced shape memory effects have been observed in several selected heusler compounds. In this study, we roughly revealed the catalytic properties of heusler alloys by investigating 12 alloys for the hydrogenation of propyne and the oxidation of carbon monoxide. The database, developed by william butlers group at the university of alabama and prof. Ferrimagnetism can be either found in perfect heusler compounds or achieved through the creation of defects in ferromagnetic heusler alloys. Pdf structural properties of magnetic heusler alloys researchgate. Heusler alloys halfmetallic materials and their properties. Structural and magnetic properties of fe2coga heusler. Vanadiumdopinginduced resonant energy levels for the. Heusler alloys consist of approximately two parts of copper, one of manganese, and one of tin. The poscar file can either be constructed using an existing cif file from an online data.
Heusler alloy article about heusler alloy by the free. Therefore, synthesizing and investigating new systems becomes an attractive subject for investigators working in this field. Some new applications of ha in spintronics and micro. This database includes calculations on a wide range of heusler alloys, including magnetic moment, stability and more. Pdf intermetallic heusler alloys are amongst the most attractive. Thin films of the heusler alloys cu2mnal and co2mnsi desy pubdb. Pdf structure of rapidly quenched gafree heusler alloys. Introductionthe heusler alloys, so named in honor of their discoverer, are composed of copper, manganese and aluminum, and are remarkable for the fact that, in certain proportions, they are ferromagnetic, although the component metals are not ferromagnetic. Materials free fulltext the forced magnetostrictions and. Heusler alloy definition is a magnetic alloy composed of the nonmagnetic metals copper, manganese, and tin approximately in the proportions cu2mnsn. Especially heusler compounds as halfmetallic ferromagnetic and topological insulators are important in condensed matter science due to their potential in magnetism and as materials for energy conversion.
Heusler reported that it was possible to make ferromagnetic alloys from nonferromagnetic constituents coppermanganese bronze and group b elements such as aluminium and tin. Heusler alloys properties, growth, applications claudia felser. Pdf fundamentals of halfmetallic fullheusler alloys. The conventional ternary heusler alloys with stoichiometric composition, x 2 yz and xyz, exist in l2 1 full heusler alloys and c1 b crystal structures semi heusler alloys, respectively, with x and y as the two transition metal tm atoms and z as a main group element. These are generally composed of nickel, manganese and gallium and can change their length by up to 10% in a magnetic field. Design of compensated ferrimagnetic heusler alloys for giant. This book gives an overview of the physics of heusler compounds ranging from fundamental properties of these alloys to their applications. Heusler alloys comprise an extensive family with diverse physical properties1. Heusler article about heusler by the free dictionary. Here we report the thermal and electronic properties of thinfilm heusler alloys based on fe2v0. Pdf study of co 2 mnal heusler alloy as half metallic. Heusler alloys have been a significant topic of research due to their unique electronic structure, which exhibits halfmetallicity, and a wide variety of properties such as magnetocalorics. Properties, growth, applications springer series in materials science book 222 kindle edition by felser, claudia, hirohata, atsufumi.
Here, we present a case study for nibased heusler compounds of the type. Any of a group of ferromagnetic nonferrous alloys typically composed of 1825% manganese, 1025% aluminum, and the balance copper explanation of heusler. Study of co 2 mnal heusler alloy as half metallic ferromagnet. Topological insulators have been predicted and recently demonstrated experimentally in a series of binary alloys. Designing rareearth free permanent magnets in heusler alloys via interstitial.
Although most heusler alloys are ferromagnets, ferrimagnetic or antiferromagnetic also called fullycompensated ferrimagnetic alloys would be more desirable for applications due to the lower external fields. Jul 28, 2015 halfheusler alloys mgagsb structure are promising thermoelectric materials. Physical properties of heusler alloys in thinfilm form. Halfheusler alloys as promising thermoelectric materials by. Ferromagnetic heusler alloys exhibited magnetic shape memory effect.
The highest dimensionless figure of merit zt obtained is. This database provides information on three families of heusler alloys, full heuslers a 2 bc, half heuslers abc and inverse heuslers abac. Halfheusler ternary compounds as new multifunctional. Heusler alloy definition of heusler alloy by merriamwebster. Ni45co5mn40sn10 heusler alloy was fabricated with elemental powders, using a powder processing route of press and sinter, in place of vacuum induction melting or arc melting route. Review of heusler compounds zhaoqiang bai,1, 2 lei shen,1, guchang han,2 and yuan ping feng1, 1 department of physics, national university of singapore, 2 science drive 3, singapore 117542, singapore 2 data storage institute, agency for science, technology and research, 5 engineering drive 1, singapore 117608, singapore abstract. Half heusler compounds based on xnisn and xcosb x ti, zr or hf have rapidly become important thermoelectric materials for converting waste heat into electricity. The effects of process parameters, such as compaction load, sintering time, and temperature, on the transformation characteristics and microstructures of the alloy were investigated.
Chapter 2 half heusler alloys as thermoelectric materials. Designing rareearth free permanent magnets in heusler alloys via interstitial doping. Tetragonal superstructure of the antiskyrmion hosting heusler. Electronic structure and physical properties of heusler. Intermetallic heusler alloys are amongst the most attractive halfmetallic systems due to the high curie temperatures and the structural similarity to the binary semiconductors. It is now show theoretically that ternary half heusler alloys have electronic.
The alloys are named after fritz heusler, 19thcentury german mining engineer and chemist. The calculations show that all fe2crx alloys are halfmetals with a magnetic moment of 3. Nov, 2019 here we report the thermal and electronic properties of thinfilm heusler alloys based on fe 2 v 0. Heusler alloy is also a typical object for studying the ordered atomic configuration and magnetic coupling for intermetallic compounds2. Heusler alloys ha are a class of materials which may be metals, semiconductors or semimetals, most of them being ferromagnets.
Among the fe 2based heusler alloys, the fe 2crz z is the main group. May 06, 2019 heusler alloys have been a significant topic of research due to their unique electronic structure, which exhibits halfmetallicity, and a wide variety of properties such as magnetocalorics, thermoelectrics, and magnetic shape memory effects. Professor ctirad uher, chair assistant professor emmanouil kioupakis associate professor lu li. Ferrimagnetism and antiferromagnetism in halfmetallic. Page a dissertation submitted in partial fulfillment of the requirements for the degree of doctor of philosophy physics in the university of michigan 2017 doctoral committee. Potential motivation of such research activities are fueled by the discovery of diverse physical and functional properties having important technological applications. As heusler alloys exhibit most of the properties of metals but have the structure of an ordered.
Any of a group of ferromagnetic nonferrous alloys typically composed of 1825% manganese, 1025% aluminum, and the balance copper explanation of heusler alloy. Uncovering high thermoelectric figure of merit in hf,zrnisn. Rnisn halfheusler phases r hf, zr, and ti are the most studied in view of thermal stability. Density functional theory calculations suggest that the.
Thermoelectric performance of a metastable thinfilm heusler. A small lack of compensation produces giant exchange bias and large coercivity. Metamagnetic transition and observation of spinfluctuations. This book gives an overview of the physics of heusler compounds ranging. Structure and magnetic properties of heusler alloy fe niz z. Among them, fe 2coga x 2 compounds appear as a new candidate for ferromagnetic shape memory alloys. Pdf heusler compounds how to tune the magnetocrystalline. Especially heusler compounds as halfmetallic ferromagnetic and topological insulators are important in condensed matter science due to their potential in. Heusler alloys are continuing to be at the forefront of active research 15. Heusler alloy, any of the first magnetic alloys composed of metals that, in their pure state, are not magnetic. Pdf a search for half metallicity in half heusler alloys. Synthesisandcharacterizationof half4metallicheusleralloys. B at their respective equilibrium lattice constants, which is in good agreement with the slaterpauling rule.
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