Research And Exploration Of New Fe-based Magnetostrictive Materials

As an important new functional materials, magnetostrictive materials has broadapplication in micro-sensors，micro drive and magnetic field. In this paper, we fabricatedFe1-xCoxalloys with different compositions and Tb1-xPrxFe3alloys by arc-melting. Structure,magnetostriction and magnetic properties of the alloys were investigated by XRD,magnetoelectric measurement system and Vibrating Sample Magnetometer. Then, elasticmodulus and Electronic structure of Fe-Co alloy is calculated via MS package by planewave and pseudopotential based on the density functional theory (DTF) and first principles,and generalized gradient approximation(GGA).Fe1-x-Cox(x=0.4~0.8) alloys were prepared by arc-melting. It is found that there arebcc and fcc phase in the Fe20Co80alloy. But only bcc phase could be find when x<0.7.Magnetostriction of the alloy changes unlinearly with the content of Co increasing. Thesamples of Fe0.3Co0.7alloy and Fe0.55Co0.45alloy have the maximum values ofmagnetostriction, these are92ppm and80ppm, respectively.We used the first principles for analysis the elastic properties of the Fe-Co alloys. Theresults show that when the composition of alloy is Fe1Co15, C11-C12<0. It indicate that thelattice of this alloy cannot keep stable. It was accord to the result of XRD. The remainingcomponents of the calculation results are in line with the mechanical stability conditions.Through the results by compute. We find that the elastic modulus of alloys increased at firstand then decreased.when the composition of Co in the alloy reached31%, the modulus ofelasticity are the largest. The modulus of elasticity of the alloy will decrease with theincreasing of Co. Combined with the experimental results, we consider that the giantmagnetostrictive in Fe0.3Co0.7alloy may caused by the soften of the materials.We also research the Tb1-xPrxFe3(x=0~1) alloys and got some interest outcome. Afterannealed, the samples of x<0.4has two phases in its internal. The main phase in the alloywas1:3phase. Also, there are2:17phase in the alloy. In addition, we found that when thex=0.4，there was a new phase in the alloy. Compared with the PDF cards, it matched to theHf1.2Zr0.8Fe diffraction phase structure. We determinates this new rare earth metalcompounds named R2Fe preliminary. In further analysis, we found that the crafts of quenchwill restrain the grow of new phase. So, we think that more research on the performance of these new rare earth intermetallic compounds was needed.