▎ 摘　　要

Single filament MgB2/Fe(Nb)/Cu wires with or without graphene doping, using Fe and Nb as sheath, were fabricated by the in-situ PIT method. The heat treatment of sample was at 670 similar to 800 degrees C for 2 h under high purity Ar atmosphere. X-ray diffraction pattern shows the main phase of the wires with heat treatment at 670 degrees C is MgB2 phase, except partial Fe2B impurity phase in Fe sheathed MgB2 wires. Microstructure analysis shows the hole between crystal grains in the wire without doping is bigger than that of Fe or Nb sheathed MgB2 wire doped with graphene. Stress-strain test results show that the tensile strain values for the wire before heat treatment are lower than those of wires after heat treatment obviously. Hardenability of Fe sheathed wires is more sharpness. The strength is the maximum for Fe sheathed wires with or without heat treatment. Four probe transfer measurement properties show that the critical current density J(c) of Nb sheathed wire heat treatment at 670 degrees C is higher than that of Fe sheathed wire at 4.2 K with the field of 2, 4 and 6 T. Nb and Fe sheathed MgB2 wires doped with graphene possess better transfer performance at 2 T. The 4 value at 2 T reaches 4.59x10(5)A/cm(2) for Nb sheathed wires. When the field is higher than 4 T, the J(c) values of Nb and Fe sheathed MgB2 wires doped with graphene are lower than that of undoped wire. The transfer property of Fe sheathed wires reduce faster than those of other samples. This indicates that the dopants incompletely enter the crystal structure, leading to the reduced flux pinning function at high field.