用固相反应法制备了La0.4Ca0.6Mn1-xCrxO3（x=0.00,0.08）多晶样品,通过XRD谱、M-T曲线、ρ~T曲线、Lnρ-T-14曲线,研究Cr^3＋替代Mn3＋对La0.4Ca0.6MnO3电荷有序相及电输运性质的影响.实验结果表明：Cr^3＋替代Mn3＋对La0.4Ca0.6MnO3电荷有序相影响明显,但对电输运性质影响不明显.原因是Cr^3＋替代Mn3＋破坏了CE型反铁磁的自旋序从而引起电荷序被破坏,由于Cr^3＋与Mn4＋具有相同的电子结构,Cr^3＋替代Mn3＋虽然破坏了体系的电荷序,但是仅形成小的铁磁区,磁结构仍为在反铁磁背景下存在少量铁磁成分,掺杂样品与母体样品的电输运性质都符合Mott的可变程跃迁模型ρ=ρ0exp（T0/T）1/4.
Polycrystalline samples of La0.4Ca0.6Mn1-xCrxO3（x=0.00,0.08） have been prepared by the solid state reaction method.The influence of Cr^3＋ substitution for Mn3＋ on the electrical transport property and charge ordering phase of La0.4Ca0.6MnO3 has been studied through the analysis of X-ray diffraction（XRD） patterns,magnetization-temperature（M～T）,resistivity-temperature（ρ～T）,and lnρ-T-1/4 curves.The results indicate that the Cr^3＋ substitution for Mn3＋ has a strong effect on the charge ordering phase of La0.4Ca0.6MnO3,however,that is weak for the electrical transport property.That is because the Cr^3＋ substitution for Mn3＋ destroys the spin order of CE-type antiferromagnetism,leading to the melting of charge ordering.However,only small ferromagnetism zone has been formed due to the same electronic structure of Cr^3＋ and Mn^4＋,and the magnetic structure possesses still a small amount of ferromagnetic component under antiferromagnetism background,which causes that the electrical transport properties of doped and matrix samples are consistent with the Mott variable range transition model ofρ=ρ0exp（T0/T）1/4.
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