The solutions to four classical problems in dynamic plasticity—the circular plate under uniform pressure, the reinforced circular cylindrical shell under uniform pressure, the free-free beam with a central concentrated force, and the circular cylindrical shell with a ring load—are examined to determine the effect of pulse shape on final plastic deformation. It is found that there is a strong dependence on pulse shape for pulses which have the same total impulse and maximum load; however, the effect of the pulse shape is virtually eliminated if the pulses have the same total impulse and “effective load.” The “effective load” is defined as the impulse divided by twice the mean time of the pulse, where the mean time is the interval between the onset of plastic deformation and the centroid of the pulse.

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Dense (Bi, Pb), Sr,Ca,Cu,O, bars were fabricated by sinter forging. The bars were highly phase-pure and exhibited strong textures in which t h e c axes of the platelike grains were preferentially aligned parallel to the pressing direction. Transport critical current densities increased with texture, reaching a maximum of 8 x io3 A cm-2 at 77 K in a seif-field. Optimal processing in air occurred at 845-850 "C.