Alloys with low thermal expansion could overcome thermal stress issues under temperature-fluctuated conditions and possess important application prospects,while they are restricted to finite chemical components and te...Alloys with low thermal expansion could overcome thermal stress issues under temperature-fluctuated conditions and possess important application prospects,while they are restricted to finite chemical components and temperature windows.In this study,we report a novel class of near-zero thermal expansion(near ZTE)alloys,ErFe_(10)V_(2−x)Mo_(x),over a wide temperature range(120–440 K).Neutron diffraction and magnetic measurements demonstrated that the ErFe_(10)V_(2−x)Mo_(x)compounds exhibited complex ferrimagnetic(FIM)structures below Curie temperature(TC).The near-ZTE behaviors were closely related to the itinerant Fe 3d moments in the collinear FIM states,as well as the geometric[−Fe−Fe−]linkages.Further,X-ray absorption near-edge structure(XANES)spectra revealed that the nonmagnetic substitution changed the electronic valence states of Fe atoms,which,in turn,changed Fe 3d moments and TC,hence,regulating the thermal expansion behaviors.Our work provides an insight into chemical modifications of thermal expansion in magnetic intermetallic compounds.展开更多
基金supported by the National Natural Science Foundation of China(21701008,21231001,21590793,and 21731001)National Postdoctoral Program for Innovative Talents(BX201700027)the Fundamental Research Funds for the Central Universities,China(FRF-IDRY-19-018).
文摘Alloys with low thermal expansion could overcome thermal stress issues under temperature-fluctuated conditions and possess important application prospects,while they are restricted to finite chemical components and temperature windows.In this study,we report a novel class of near-zero thermal expansion(near ZTE)alloys,ErFe_(10)V_(2−x)Mo_(x),over a wide temperature range(120–440 K).Neutron diffraction and magnetic measurements demonstrated that the ErFe_(10)V_(2−x)Mo_(x)compounds exhibited complex ferrimagnetic(FIM)structures below Curie temperature(TC).The near-ZTE behaviors were closely related to the itinerant Fe 3d moments in the collinear FIM states,as well as the geometric[−Fe−Fe−]linkages.Further,X-ray absorption near-edge structure(XANES)spectra revealed that the nonmagnetic substitution changed the electronic valence states of Fe atoms,which,in turn,changed Fe 3d moments and TC,hence,regulating the thermal expansion behaviors.Our work provides an insight into chemical modifications of thermal expansion in magnetic intermetallic compounds.
