Optimization on magnetic transitions and magnetostriction in TbxDyyNdz(Fe0.9Co0.1)1.93 compounds

Abstract

The structure, magnetic transitions, and magnetostriction of Tb x Dy y Nd z (Fe 0.9 Co 0.1 ) 1.93 polycrystalline compounds have been investigated, with the ratio of x, y, and z spanning the line of minimum magnetic anisotropy. Anisotropy compensation with lower Tb content was realized in Tb 0.253 Dy 0.657 Nd 0.09 (Fe 0.9 Co 0.1 ) 1.93 compound. The spin configuration diagram accompanied with different crystal structures was constructed to illustrate the arrangement for the easy magnetization direction and crystal structure. An optimized effect on magnetostriction especially at the relatively low field of 1 kOe (197 ppm) was observed in Tb 0.253 Dy 0.657 Nd 0.09 (Fe 0.9 Co 0.1 ) 1.93 compound, which is about two times larger than that of the sample free of Nd (62 ppm). Meanwhile, the polycrystalline saturation magnetostriction (k s ¼ 945 ppm) of Tb 0.253 Dy 0.657 Nd 0.09 (Fe 0.9 Co 0.1 ) 1.93 is even much larger than that of the Ho-doped multicomponent single crystal compound Tb 0.2 Dy 0.22 Ho 0.58 Fe 2 (k s ¼ 530 ppm). Low content of heavy rare earth Tb, high Curie temperature, and large ratio between magnetostriction and the absolute value of the first anisotropy constant k a /jK 1 j were obtained in Tb 0.253 Dy 0.657 Nd 0.09 (Fe 0.9 Co 0.1 ) 1.93 compound, which may make it a potential material for magnetostrictive application. V C 2013 AIP Publishing LLC. [http://dx.

Optimization on magnetic anisotropy and magnetostriction in Tb Ho0.8−Pr0.2(Fe0.8Co0.2)1.93 compounds

“…It is known that spontaneous magnetostriction leads to crystalstructural distortion of Laves phase compound when it is cooled down below its Curie temperature [9,16]. A rhombohedral distortion occurs and the XRD (440) reflection is doubly split when EMD lies along o111 4 axis, while a tetrahedral distortion follows and the XRD (440) reflection keeps a single peak for o 100 4 EMD.…”

“…Recently, new progress was attained by introducing Co as substitutional atoms into RFe 2 , stabilizing the formation of light rare earth-based C15 structure and improving the intrinsic magnetic properties [3,[7][8][9][10]. It was reported that the 20 at% Co substitution for Fe could increase Curie temperature T C and change spin-reorientation temperature, which affects intensively on magnetic anisotropy at room temperature.…”

Recent Advances in Magnetostrictive Tb-Dy-Fe Alloys

“…Similar to Pr, many studies [43][44][45][46][47][48][49][50][51][52] have shown that the appropriate replacement of heavy rare-earth Tb and Dy with light rare-earth Nd is an effective approach to decrease magnetocrystalline anisotropy and improve magnetostriction. For example, the Tb 0.4 Dy 0.5 Nd 0.1 Fe 1.93 compound possessed the large magnetostriction value of 1300 ppm at 5 kOe [47].…”

Enhanced magnetoelastic effect in Laves (Tb,Dy)Fe2 alloys with the joint introduction of Pr and Nd

“…In this way, the well-known Tb x Dy 1-x Fe 2 (Terfenol-D) system is constructed, of which Tb is partly substituted by Dy with the opposite sign of K 1 . Moreover, by introducing a third rare-earth element, such as Ho, Pr and Nd, an additional degree of freedom can be obtained, and subsequently both the first-and the second-order anisotropy constants (K 1 and K 2 ) could be minimized, which allows a better way in applications [5][6][7][8]. It was reported that in the (Tb,Dy)Fe 2 system, the introduction of Ho can lower magnetostrictive hysteresis with only slightly lower magnetostriction, while the introduction of Nd contributes significantly to the relatively low magnetocrystalline anisotropy and leads to the increase of magnetostriction.…”