| 摘要 |
PURPOSE:To make a product superior in dimensional accuracy and appearance without generating burning flaw or slip by making a tool for plastic working with a number of small recesses on its smooth plane and making the diameter and depth of the size of each recess into a specified value respectively. CONSTITUTION:The tool 1 is provided with the recesses 3 of the diameter of 5-50mum and depth of 0.5-50mum on the smooth surface 2. These recesses 3 are provided on the whole of the surface of tool so that the total area of the recesses 3 becomes 5-50% to the surface area of the tool before recessing. When a metal is plastically worked with this tool, it is worked in a such state that a part of the material 4 is entered into these recesses 3. Thus, the coefficient of friction is increased and also lubricating oil in the recesses 3 is pressed out and extended on the smooth surface part 1. In this way, because burning flaw and slip are hard to generate even if it is plastic working at high speed and high working rate, the product is superior in dimensional accuracy and appearance. |
