Study On Preparation And Properties Of FeSiBP(Cu) Amorphous Alloy

In this paper,a new amorphous alloy composition of Fe₇₆Si_xB_yP_24-x-yis obtained by designing the composition triangle of the three element contents of Si,B,and P.The influence of the change of the content of the metal-like elements Si,B,and P on the amorphous structure and the amorphous forming ability of the Fe Si BP amorphous alloy system was explored.Meanwhile,a region with strong amorphous forming ability was choose to study the effect of the change of metal-like element content in this region on the mechanical and magnetic properties of amorphous alloys.On the basis of this research,Cu element was added,and a new Fe Si BPCu amorphous alloy system was designed.The influence of Cu element addition on the amorphous forming ability,mechanical properties and magnetic properties of Fe Si BP amorphous alloy system was explored.The main conclusions are as follows:（1）When the contents of Si,B,and P are 19.2%,the prepared strips show a coexisting structure of amorphous and crystalline states.In the alloys with a content of less than 19.2%,the prepared alloy strips are all amorphous strips.When the element content is 4.8%≤Si≤12%,2.4%≤B≤12%,4.8%≤P≤14.4%,the amorphous alloy has a significant glass transition temperature.The four components of Fe76Si9.6B7.2P7.2,Fe76Si9.6B9.6P4.8,Fe76Si7.2B12P4.8 and Fe76Si7.2B9.6P7.2 have the largest subcooled liquid phase interval,which are 38K,45K,47K and 40K respectively.The quadrilateral composed of these four components has strong amorphous forming ability,and the element content in this region is 7.2%≤Si≤9.6%,7.2%≤B≤12%,4.8%≤P≤7.2%.（2）The new alloy composition is designed and prepared in the region with strong amorphous forming ability as Fe76Si8.4B10.8P4.8,Fe76Si8.9B9.4P5.7 and Fe76Si8.4B9.6P6.After the thermodynamic analysis of the three amorphous alloy bars by differential scanning calorimeter,the DSC curve shows that the ferromagnetic transition temperature T_c,the glass transition temperature T_g,and the crystallization initiation temperature T_x change little,the supercooled liquid phase interval is 45K above,and the ability of amorphous forming is strong.After the compression test of the three amorphous alloys,the overall The elastic limit and the breaking strength have a small change range,all above 3200MPa.After the end of the elastic stage,they all break through the plastic deformation stage.After the magnetic properties of the three amorphous alloys are analyzed by the vibrating sample magnetometer and AC and DC B-H instrument,the saturation magnetic induction is 169.1emu/g、168.1emu/g、165emu/g,and the coercivity is 2.51A/m,2.5A/m,2.52A/m.（3）The addition of Cu element to Fe₇₆Si_8.4B_10.8P_4.8,Fe₇₆Si_8.9B_9.4P_5.7 and Fe₇₆Si_8.4B_9.6P₆ amorphous alloy composition will change the internal crystallization process of the alloy,reduce the subcritical nucleation energy of the first crystalline phase promote the precipitation of the first crystalline phase,and reduce the ability to form amorphous;the saturation magnetic induction of the amorphous alloy will decrease and the coercivity will increase;the fracture strength of the alloy will increase,generally reaching 3300MPa,and the maximum plastic strain is 0.9%.