We prepared MgB
2 thin films on non-textured aluminum (Al) tapes using an electron-beam evaporation technique. Single phases of MgB
2 films with a
c-axis and without biaxial crystal orientation were obtained with the critical temperatures (
Tc) of 19-29.8 K, corresponding to the substrate temperature of 200-280°C. The magnetic field dependences of the critical current density (
Jc) were measured at 4.2, 10 and 20 K in the field of 0-12 T applied parallel and perpendicular to the film surface. The
Jc at 10 and 20 K in the self field were 3.1×10
6 A/cm
2 and 1.2×10
6 A/cm
2, respectively.
Jc at 4.2 K exceeded 10
6 A/cm
2 in the parallel and perpendicular fields of between 0 and 10 T. These results suggest that a MgB
2 coated conductor may be one of the most promising candidates for practical MgB
2 superconducting wires.
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