Low temperature magnetic and magnetostrictive properties in cubic Laves alloys**Project supported by the National Natural Science Foundation of China (Grant No. U1232210), the Science Foundation of Guangxi Zhuang Autonomous Region, China (Grant No. 2015GXNSFBA139020), and the Project of the Enhancement of the Basic Ability of Teachers of Guangxi Zhuang Autonomous Region, China (Grant No. KY2016YB068).

Abstract

The structures, spin reorientations, magnetic, and magnetostrictive properties of the polycrystalline Pr(Fe1−xCox)1.9 (x = 0–1.0) cubic laves phase alloys between 5 K and 300 K are investigated. Large low-field magnetostrictions are observed at 5 K in the alloys with x = 0.2 and 0.4 due to the low magnetic anisotropies of these two alloys. A large negative magnetostriction of about −1130 ppm is found in PrCo1.9 alloy at 5 K. The magnetizations of the alloys with decrease abnormally at the spin reorientation temperature , and an abnormity is detected in the alloy with x = 1.0 at its Curie temperature (45 K). The substitution of Fe by Co increases the value of in the alloy with x value increasing from 0.0 to 0.4, and then reduces the value of with x value further increasing to 0.6.