Nondestructive inspection of patterns formed on inner surfaces of small diameter pipes
Inspection of patterns formed on inner surfaces of copper pipes with a small diameter of 2 mm was investigated. At first, space patterns with widths of 20-30 μm were lithographically formed using a handmade laser-scan exposure system. The exposure system was equipped with a monitoring system of a laser beam spot irradiated on the inner surface of pipe for the exposure. Pattern inspection was executed utilizing this monitoring system. In the case of exposure for patterning, the beam monitor was used for confirming the position and size of the laser beam. However, being prevented by the bright beam spot, background views were not clearly observed. For this reason, the pinhole that is initially inserted for reshaping the laser beam and making an appropriately small spot was removed, and the brightness of the beam spot was mitigated. In addition, inspected camera images were stored as video images in a personal computer using a video capture. As samples for the inspection, space patterns in resist films and groove patterns etched in copper pipes were used. As a result, resist space patterns were observed quite clearly, and pattern widths were measurable. In addition, the measured pattern widths almost agreed with the ones measured using a scanning electron microscope after cutting a half of the pipe off. On the other hand, etched groove patterns were not so clear as resist patterns. However, it was clarified that fatal pattern defects such as kinks, shifts, and breaks were detected, if the pattern images stored in the computer were carefully investigated. The new nondestructive inspection method is effective.
On the application of electrochemical machining for inner surface polishing of gun barrel chamber
Inner surface polishing of complex parts with high precision can be easily done by electrochemical polishing method. In this research, cartridge house inner surface electrochemical polishing of a gun pipe, with numerous serial surface angles, is analyzed. So that, according to the various set ups, the optimized polishing parameters are obtained. The comparison between electrochemical polishing and conventional methods from this point of view, shows good advantages of this method, so that, the machining time is more than 30 times less and with very high-surface quality. Besides, the dimensional accuracy of the workpiece repeatability process in this polishing method is noticeable.
Anomalous Annealing Behavior of Arsenic Implanted Silicon as a Function of Dose and Energy
Anomalous annealing behavior of damage in As implanted Si has been investigated by channeling effect measurements. Room temperature As implants with doses from 1014 to 2 × 1016cm-2 at energies ranging from 50 to 250 keV into Si were annealed over the range of 600°C to 1100°C. Anneal temperatures ≥ 950°C reduce the disorder for ion doses of 0.5 to 1 × 1016 cm-2 at energies between 50 and 250 keV. Anomalously high residual disorder was found for the intermediate doses of 2 × 1014 to 2 × 10/cm2 implanted above 100 keV. For this intermediate dose, annealing of implants performed at liquid nitrogen temperatures did not show significant reduction in this damage. However implants at 200° to 300°C indicate a lower amount of damage compared to the room temperature implants.