Enhanced mechanical properties of giant magnetostrictive Tb-Dy-Fe alloy via constructing semi-coherent interface between matrix phase and ductile grain boundary phase  

作　　者：Jiheng Li Zhiguang Zhou Zhaopeng Han Zijing Yang Xiaoqian Bao Xuexu Gao 

机构地区：[1]State Key Laboratory for Advanced Metals and Materials,University of Science and Technology Beijing,Beijing 100083,China [2]Beijing Research Institute of Mechanical&Electrical Technolgy Co.,Ltd.CSM,Beijing 100083,China

出　　处：《Journal of Materials Science & Technology》2024年第8期185-193,共9页材料科学技术（英文版）

基　　金：supported by the National Key R&D Program of China(No.2021YFB3501403);the State Key Laboratory for Advanced Metals and Materials(Nos.2017Z-11 and 2018Z-07);the Fundamental Research Funds for the Central Universities(Nos.FRF-GF-17-B2,FRF-GF-19-028B and FRF-GF-20-23B).

摘　　要：Giant magnetostrictive Tb-Dy-Fe alloys in the form of thin sheets or fine wires are required in precision micro-actuators and sensors.However,Tb-Dy-Fe alloys are too brittle to undergo machining and application.In the present work,we investigated the effects of diffusing the Dy_(36 )Cu_(64 )alloy into the grain boundary phases of the<110>-oriented Tb_(0.30) Dy_(0.70 )Fe_(1.95) alloy to modify the microstructural,mechanical,and magnetostrictive properties.Microstructural analysis revealed the introduction of Cu into the grain boundary phase through the diffusion treatment,transforming the brittle rare earth(RE)-rich grain boundary phase into a ductile(Tb,Dy)Cu grain boundary phase and changing the non-coherent interface to a semi-coherent one between the(Tb,Dy)Fe_(2) matrix phase and the grain boundary phase without affecting the microstructure of the matrix phase.The as-diffused Tb_(0.30 )Dy_(0.70) Fe_(1.95) alloy exhibited significantly improved mechanical properties,with its tensile strength,bending strength,and fracture toughness at room temperature increasing to 44.6 MPa,106.8 MPa,and 2.36 MPa m^(1/2),respectively,which were 2,2.4,and 1.5 times those of the non-diffused sample.This was attributed to the formation of ductile(Tb,Dy)Cu grain boundary phase and semi-coherent interfaces.Furthermore,the magnetostrictive strain of the as-diffused Tb_(0.30) Dy_(0.70) Fe_(1.95) alloy reached 1448 ppm,suggesting that there was minimal impact on the magnetostrictive properties,due to the small influence of grain boundary diffusion on the matrix phase.

关 键 词：Tb-Dy-Fe alloys MAGNETOSTRICTION Mechanical performance Grain boundary diffusion Semi-coherent interface 

分 类 号：TG14[一般工业技术—材料科学与工程]