  A commercial stainless steel tube was employed to synthesize MgB2. The
specimen was prepared by a stoichiometric mixture of Mg and B. The specimen
that had been enveloped in the commercial stainless steel tube was synthesized
for 2 hours at 1193 K. X-ray spectra showed there were no second phases like
MgO. The transition temperature of the specimen was 37.5 K with a sharp
transition width within 1K. The specimen showed a good connection between
grains and critical current density as calculated with the Bean model is more
than 100,000 A/cm2 at 20 K and in zero field.
