METAL DEFORMATION WITH ULTRASOUND.

An investigation into the formability properties of various metals under the application of ultrasonic (20 kHz) energy was conducted. Compression tests on cylindrical metal slugs (1018 hot rolled steel, 6063 aluminum in both the hardened and annealed conditions, and primary cell magnesium) were performed to determine if ultrasound would be beneficial in deforming these materials and, in particular, whether the ductility could be increased or the deformation stresses reduced with ultrasound. It was found that the forming stresses were reduced as much as 78 percent for the annealed aluminum and 45 percent for steel, with smaller reductions occurring for the unannealed aluminum and magnesium. Also the largest stress reductions occurred at the slowest forming speeds when ultrasound was applied at small strains.