Powder metallurgy gear molds are one of the necessary conditions for powder metallurgy. Powder metallurgy has unique properties that cannot be obtained by conventional casting methods, such as chemical composition and physical properties. The resulting powder metallurgy parts are produced by the use of a wheeled mechanical part-gear that transmits torque through the engagement of the teeth.
The powder metallurgy gear mold is generally composed of upper punch, lower punch, core rod and middle mold; powder metallurgy gear forming will undergo three processes of filling, pressing and demoulding. Firstly, the powder is filled in the cavity of the powder metallurgy gear mold, and then punched into the middle mold to press the powder into a green embryo, and finally the upper punch is reset, the middle mold is moved down, and the raw embryo is taken out of the mold cavity.
In order to solve the problem that the manufacturing precision of the powder metallurgy gear mold is not high, the disc grinding wheel CNC internal tooth forming grinding technology can be used to improve the mold precision. After the known tooth shape is converted to the calculation plane according to the relative positional relationship, the sand contour shape calculation is carried out by the numerical simulation envelope method, and the software is used for calculation verification and error analysis. As a result, the calculation error of the powder metallurgy gear mold can be controlled within 0.0001 mm to meet the requirements of high-precision gear mold manufacturing.