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The results of the preliminary hazard analysis on the Laboratory Demonstration Electromagnetic Launcher are described. This analysis was based on system concepts and inherent known hazards. This work has concluded that although serious hazards do exist, a properly designed laboratory and detailed operating plan can ensure personnel safety and minimize the potential for system or component damage.

The main purpose of this work was to develop and employ new metallurgical techniques for determining the microstructural features controlling the critical current of Type II superconductors. Another purpose was to study the critical current in thin films by magnetization measurements. From the data both the critical current density and magnetic flux pinning force as a function of field were calculated. The study in Appendix I identifies dislocation cell boundaries as the prominent microstructural feature of commercial multifilamentary superconductors. This feature is correlated with critical current and guidelines are provided for critical current enhancement in commercial conductors. The report in Appendix II describes a new technique for measuring grain size and thicknesses of the thin layers on the order of .5 micrometer which occur in the fabrication of Nb3Sn by diffusion reactions. The method is rapid and inexpensive compared to competing techniques and will be useful in new conductor development.

Magnetic ordering and superconductivity have been investigated in Mn and Eu doped SnTe. The study shows that Mn(++) spins couple ferromagnetically and e (++) spins antiferromagnetically. Heat capacity results showed anomalies attributable to Mn(++) coupling. The effect of magnetic impurity (x) on the superconducting transition temperature (T) was studied. This study shows a non-linear dependence of T on x. An anomalous effect of particle size on T in SnTe has been observed. (Author)