Manufacturing technology for the high-precision right-angle square body

This study proposed and evaluated a highly precise method employing various diameters and shapes of punch to manufacture right-angled square-bodied products. In this method, a trough is not only engraved on the die but also designed into the punch. Five diameters and shapes of the punch were collocated with a circular trough around the square shape of a die cavity. In the tests, a ram descended to a fixed level, and part of the billet was forced into the trough without touching its bottom. This causes high hydrostatic stress on the cutting edge of the die. The pressure substantially reduces the occurrence of fractures in test products. The punch with a square trough engraved on its face produced a product with favorable shape and precision compared with other punch shapes. The results revealed that the proposed method can produce a product with a long and burnished surface with a roughness of 0.02–0.12 μm. The tolerance band for the width and thickness ranges from IT1 to IT3, and that for the right angle is 0.02–0.06°. The proposed method is a new rapid prototyping technology and has greater levels of precision than conventional manufacturing methods.