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Structural changes in the thin film–thick film transition of Ni, electrodeposited onto polycrystalline copper substrates, were observed. Nickel was plated onto electropolished substrates from a Watts bath held at 50 °C at a current density of 1 mA/cm2. The Cu substrates, chemically stripped from the thick Ni deposits, were subsequently electrolytically thinned to prepare transmission electron microscope (TEM) specimens. Scanning electron microscope (SEM) observations were made on the Ni deposits before stripping. Epitaxial growth was observed in deposits of 0.1-μ thickness, with traces of polycrystallinity. Deposits acquired a relatively uniform polycrystalline grain structure at about 5-μ thickness, and only slight increases in grain size were observed with increased thickness above 5 μ.

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Palladium single-crystal films have been prepared by Matthews in ultra-high vacuum by evaporation onto (001) NaCl substrates cleaved in-situ, and maintained at ∼ 350° C. Murr has also produced large-grained and single-crystal Pd films by high-rate evaporation onto (001) NaCl air-cleaved substrates at 350°C. In the present work, very large (∼ 3cm2), continuous single-crystal films of Pd have been prepared by flash evaporation onto air-cleaved (001) NaCl substrates at temperatures at or below 250°C. Evaporation rates estimated to be ≧ 2000 Å/sec, were obtained by effectively short-circuiting 1 mil tungsten evaporation boats in a self-regulating system which maintained an optimum load current of approximately 90 amperes; corresponding to a current density through the boat of ∼ 4 × 104 amperes/cm2.

Uniaxial compression tests and hydrostatic tests at pressures up to 27 kbars have been performed to determine operating slip systems in single crystal and polycrystal1ine beryllium. A recent study has been made of wave propagation in single crystal beryllium by shock loading to selectively activate various slip systems, and this has been followed by a study of wave propagation and spallation in textured, polycrystal1ine beryllium. An alteration in the X-ray diffraction pattern has been noted after shock loading, but this alteration has not yet been correlated with any structural change occurring during shock loading of polycrystal1ine beryllium.This study is being conducted in an effort to characterize the effects of shock loading on textured, polycrystal1ine beryllium. Samples were fabricated from a billet of Kawecki-Berylco hot pressed HP-10 beryllium.