James S. Sovey

Adhesive bonding of ion beam textured metals and fluoropolymers

An electron bombardment argon ion source was used to ion etch various metals and fluoropolymers. The metal and fluoropolymers were exposed to 0.5–1.0‐keV Ar ions at ion current densities of 0.2–1.5 mA/cm2 for various exposure times. The resulting surface texture is in the form of needles or spires whose vertical dimensions may range from tenths to hundreds of micrometers, depending on the selection of beam energy, ion current density, and etch time. The bonding of textured surfaces is accomplished by ion beam texturing mating pieces of either metals or fluoropolymers and applying a bonding agent which wets in and around the microscopic conelike structures. After bonding, both tensile and shear strength measurements were made on the samples. Also tested, for comparison’s sake, were untextured and chemically etched fluoropolymers. The results of these measurements are presented in this paper.

Optical and electrical properties of ion-beam-textured Kapton and Teflon

An electron bombardment argon ion source was used to ion etch polyimide (Kapton) and fluorinated ethylene propylene, FEP (Teflon). Samples of polyimide and FEP were exposed to 0.5–1.0‐keV Ar ions at ion current densities of 1.0–1.8 mA/cm2 for various exposure times. Changes in the optical and electrical properties of the samples were used to characterize the exposure. Spectral reflectance and transmitance measurements were made between 0.33 and 2.6 μm using an integrating sphere after each exposure. From these measurements, values of solar absorptance were obtained. Total emittance measurements were also recorded for some samples. Surface resitivity was used to determine changes in the electrical conductivity of the etched samples. A scanning electron microscope was used to record surface structure after exposure. Presented in the paper are spectral optical data, resistivity measurements, calculated absorptance and emittance measurements, along with photomicrographs of the surface for the various exposures to Ar ions.