| 摘要 |
A reusable die for cold forging includes a metal casing, a bottom cover which has metal supporters welded on it and keyholes, and a film having desirable shape corresponding to the die cavity. The film is made of PET or PVC and provided at the top of the casing. Several layers of "cloth" of Kevlar fibre are placed into the casing, serving as upper stuffing, and several layers of stainless steel net are placed into the casing, serving as lower stuffing. The casing is inversed and covered by the bottom cover. Liquid mercury following steel balls or iron sand is filled into the casing from the keyholes until the casing is full. The mercury is rapidly cooled and solidified at a temperature lower than -40 DEG C, so that the die which can withstand the force of cold forging is completed. After the processing of the forging, the die can be thawed under the room temperature, and the mercury can be reclaimed. By replacing the film with a new one and repeating the steps mentioned above, a new reusable cold forging die with desirable cavity shape is obtained. |
