Magnetic Properties of Hexagonal Close-Packed Structure Type Co–Ir Binary Alloys

Abstract

The magnetic properties of alloys of the perfect hcp crystal structure type were studied by means of a magnetic balance and a pendulum-type magnetometer, and the following results were obtained;The crystal magnetic anisotropy energies of hcp type Co-Ir alloys rapidly

X-ray magnetic circular dichroism at IrL2,3 edges in Fe100−x Ir x and Co100−x Ir x alloys: Magnetism of 5d electronic states

“…The orbital and spin magnetic moments of Ir in Co-Ir alloys could be extracted from the XAS and XMCD spectra, following the procedure described above for Fe-Ir alloys by assuming a 5d 8 Table 2. Orbital magnetic moment µ orb , spin magnetic moment µ spin , their ratio µ orb /µ spin and the total magnetic moment µ tot of Ir in Co-Ir alloys determined from the XMCD data by applying the sum rules.…”

“…Similarly, taking the total moment of Co as 1.716 µ B [8], and scaling it with the number of Co in the 1NN shell, we obtain the magnetic moment µ Co of Co in the alloys. These are listed in column 5 of table 2.…”

“…The Curie temperature of the alloys with x = 3, 10 and 17 are higher than the room temperature. Co 100−x Ir x also order ferromagnetically in the Ir composition range of x = 0-35 with a Curie temperature much higher than the room temperature [8]. Presently, there is no direct information on the magnetic behavior of Ir as a function of Ir composition in these alloys.…”

A New Highly Anisotropic Rh‐Based Heusler Compound for Magnetic Recording

“…Rh, Ir, Pd and Pt are all possible choices, since they are in the same group as Co or Ni and they may exhibit a significant induced magnetization 37,38,45 . In fact, Pd is already ferromagnetic with Tc = 17 K if lightly doped with 0.5% of Co 46 and when it is alloyed with 50% Co, it has the highest Tc among the binary compounds CoRh (550 K), CoIr (40 K), CoPd (950 K) and CoPt (840 K) 47,48 . Our study outlines the design principles for new rare-earth free hard magnets, but it is unrealistic to imagine that Rh-based alloys will ever be used as bulk functional materials, in view of its high cost.…”

“…[ 37,38,46 ] In fact, Pd is already ferromagnetic with T c = 17 K if lightly doped with 0.5% of Co [ 47 ] and when it is alloyed with 50% Co, it has the highest T c among the binary compounds CoRh (550 K), CoIr (40 K), CoPd (950 K), and CoPt (840 K). [ 48,49 ] Our study outlines the design principles for new rare‐earth‐free hard magnets, but it is unrealistic to imagine that Rh‐based alloys will ever be used as bulk functional materials, in view of its high cost. This is much less important in functional thin films, because the quantities used are tiny.…”