【摘要】 研究了MnFeP0.56Si0.44Bx(x=0,0.01,0.02,0.03,0.04)系列合金的物相与磁热效应.室温XRD表明,该系列合金主相均为Fe2P型六角结构,空间群为P62m;B含量为x=0～0.02时,合金存在Fe3Si型第二相,空间群为Fm3m.随着B含量的增加,晶格常数有a增大、c减小的趋势.由M-T曲线可知,随着B含量的增加,合金的居里温度TC线性增加,热滞ΔThys逐渐减小.x=0,0.01,0.02,0.03,0.04时,在外磁场变化为0～1.5T下,由等温M-B曲线得到合金的最大等温磁熵变ΔSM max分别为3.0,4.8,4.3,8.1,10.0J/kg·K.更多还原

【Abstract】 Phase and magnetocaloric effect in MnFeP0.56 Si0.44 Bx(x=0,0.01,0.02,0.03,0.04)alloys have been investigated.X-ray diffraction shows that the alloys mainly crystallize in the Fe2P-type hexagonal structure(space group P62m)with second phase of Fe3 Si(space group Fm3m),when the B content x= 0～0.02.It is found that the lattice parameter aincreases and the lattice parameter cslightly decreases with increasing x,and the unit cell volume does not obviously change.From the M-Tcurves of alloys,it can be found that Curie temperature increases linearly and the thermal hysteresis decreases gradually of the alloys.When x=0,0.01,0.02,0.03,0.04,the maximal MEC is obtained from the curves of isothermal magnetization for magnetic field change from 0to 1.5Tis 3.0,4.8,4.3,8.1,10.0J/kg·K,respectively.更多还原