Analysis on Fe3CoNiCuCrx medium-entropy damping alloys with excellent comprehensive properties
GENG Ningning
MA Yuqi
ZHOU Yingchun
WANG Hongding
ZHANG Wei
QIU Keqiang
Abstract：[Objective]In recent years,the development and progress of science and technology has brought many conveniences to people's production and lives,whereas potential hazards(such as vibration and noise)have also arisen.The generation of vibration aggravates the damage of parts,and the emergence of noise endangers people's health.To deal with these problems,damping alloys that can absorb vibration energy have gradually garnered people's attention.However,traditional damping alloys have a single damping mechanism and poor mechanical performance,failing to realize a variety of practical applications.Therefore,it is urgent to develop a new material that takes into account both.The emergence of multi-principal-element alloys makes the idea possible.The unique construction makes the alloys have good mechanical properties and damping properties.Therefore,it is of great significance to study the relationship between the microstructure and damping properties of multi-principal-element alloys.[Methods]To realize good damping properties and excellent mechanical properties of alloys,Fe3CoNiCuCrx(x=2.0,2.5,2.75,3.0,3.5)medium-entropy alloys were prepared by an arc melting furnace and a vacuum induction furnace.The phase structures of the alloys were studied by X-ray diffraction(XRD)and transmission electron microscopy(TEM).The microstructure,phase distribution,and phase volume fraction of the alloys were characterized by a scanning electron microscope equipped with an electron backscatter diffraction(EBSD)probe.The tensile properties of the alloys were tested by a universal mechanical testing machine,and the damping properties of the alloys were tested by a dynamic mechanical analyzer.The effects of the variation of the Cr molar ratio on the phase composition and damping properties of the alloys were studied by increasing the molar ratio of the Cr element.[Results]The phase composition of the alloys changes from the face-centered cubic(FCC)phase to the FCC phase and the body-centered cubic(BCC)phase with the increase in the molar ratio of the Cr element.The formation of the two-phase structure makes the phases in the alloys grow competitively,thus reducing the average grain size of the alloys.The tensile strengths of the alloys increase from 329 MPa to 779 MPa.However,the plasticity of the alloys deteriorates,and the plastic strain is reduced from 35.45％to 1.72％.When the Cr molar ratio reaches 3.0,the damping capacity index of the alloy reaches the highest value of 0.052.With an increase in the molar ratio of the Cr element,the volume fractions of the BCC phase in the alloys gradually increase,which improves not only the tensile strengths of the alloys but also their ferromagnetic damping properties.The match of the volume fractions and morphologies of the FCC and BCC phases improves the interface damping properties of the alloys,and the unique mesh structure formed by embedding the soft FCC into the hard BCC matrix improves the damping properties of the alloys to a certain extent.[Conclusion]Under the joint influence of ferromagnetic damping,interface damping,and morphologies of the alloy,the Fe3CoNiCuCr3.0 alloy has not only excellent tensile properties but also high damping properties.
Keywords：medium-entropy alloyphase compositionmicrostructuredamping capacityferromagnetic dampinginterface dampingvolume fraction of body-centered cubic phasetensile property
Publication Date：2025-03-31
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：9( 205-213 )