GdCoAl系块非晶的磁热性能研究.docx

AbstractAbstract Abstract Abstract Bulk Metallic Glasses(BMGs)were thought to be one of new materials which have extensive applying prospects because of their unique properties．While Gd-based BMGs with Magnetocaloric Effect(MCE)make them have clear advantage，which open up a new applicable field for BMGs．T11is paper study the effects of doped elements to magnetic properties of Gd-Co—A1 alloys by means of mixing Ge，Cu into Gd—Co—AI alloys and get a few results．The main research contents and results are outlined as follows： 1．Ingots with a nominal composition of Gd60C026A114， Gd55ColsAl30， Gd60C026(A112Ge2)， Gd60C026(AlioGe4)， Gd60C026(AlgGe6)， Gd60C026(A16Ges)， Gd60C026(A112Cu2)， Gd60C026(Al_loCuO， Gd60C026(AlsCu6)， Gd60C026(h16Cus)， GdeoNi l sAl25 and GdssNi25A120 were prepared by arc-melting the mixture of high-purity Gd，Co，Ni，A1 and Ge，Cu in Ti—gettered argon atmosphere．Each ingot Was remelted for five times to ensure the homogeneity of composition iIl samples，and then WaS injected into a copper mold to obtain cylindrical rod． 2．Using X·ray diffraction(XRD)and differential scanning calorimeter(DSC) methods，microstmcture of Gd-Co-A1 amorphous alloys were analyzed，and the effects of doped elements Ge，Cu and Ni to microstructure and thermal stability of Gd—Co-AI alloys Were studied．The research results showed that the thermal stability of Gd60C026(All4．xGex)alloy WaS improved with increaSing content of Ge and a small quantity of Ge strengthened the glass forming ability of Gd60C026A1 14，the thermal stability of Gd60C026(All4-xCu0 alloy Was not enhanced when the content of Cu Was increased，while the thermal stability of alloy Was reduced when a small quantity of Ni Was added． 3．Using superconducting quantum magnetometer(SQUID)，the magnetic properties of Gd60C026AIl4 and Gd55ColsAl30 alloys were compared．The magnetic entropy of Gd60C026A114 alloy WaS close to that of metal Gd at 5 T magnetic field． Key word：bulk metallic glaSses，Gd—Co·A1，magnetocaloric effect,magneti