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Dislocation emission from the crack tip in copper under mode II loading is simulated with molecular dynamics method. After 26 partial dislocations are emitted and then relaxed to reach the equilibrium under the constant displacement, the double pile-ups (including an inverse pile-up and a pile-up) are formed. i.e., the first dislocation is piled up before the obstruction, and the last dislocation is piled up ahead of the crack tip. These results conform to the TEM observations.

Summary form only given. This paper describes the details of design and construction of the device that is able to produce three high-voltage pulses of 200 kV sequentially. The device consists of four pulse-forming lines connected in series by three switches, and three Marx generators to charge the PFLs. The interval between pulses, determined by triggering pulses, ranges from 0 to 1mus. Two kinds of switches, V/N switch and coaxial switch, have been tested on the device. Although pulses obtained at the matched resistance load remain stable, due to changing of the state of the switches, the quality of second and third pulses are worse than the first one.

A V/N switch for a multi-pulse generator has been designed, constructed and tested. The switch, using a spark gap to isolate triggered pulse and a multi-stage triggered electrode to cause the breakdown more quickly, can work at 600 kV with the time jitter less than 2 ns and the rising time less than 20 ns. Compared to other types of pulsed high-voltage switch, the N/V switch can operated stably by using triggered pulse with a relatively lower voltage and at lower cost. However, under specific circumstance, performance of the switch deteriorates, which is also discussed in this paper.

An investigation was made of the higher-order (up to sixth) spectra of coherent anti-Stokes and Stokes Raman scattering in calcite.