Research And Development Of Electrical Discharge Surface Hardening Equipment Applied To Aero-engine Turbine Labyrinth Teeth

Conductive electrodes can be deposited on metallic substrates by electrical dischargesurface hardening process and a coating with excellent properties and metallurgical bonedwith substrates can be produced to heighten the hardness and wear resistance of workpieces'surfaces. Aero-engine turbine labyrinth teeth suffer serious abrasion during running. weresearched a special electrical discharge surface hardening equipment (SANSCH100V/50A)by which deposit material (YT-15) on labyrinth teeth to advance its wear resistance. In this paper, by analyzing electrical discharge surface hardening and character ofworkpiece and electrode, a whole project, vibrated electrode and high frequency pulse powerwere designed. This equipment was reconstructed basing on C630M and realizedmechanization and automatization. Choosing intelligentized element, IGBT(Insolated Gate Bipolar Transistor), This paperhas designed a high frequency pulse power supply of volume 5KW, working frequency20KHz, and provided the working theory of half-bridge type invert circuit and DC voltagechopped circuit, and provided the design and type chosen of the main electronic element. Thecontrol circuit of high frequency pulse power consists of two parts: Inverter Control andChopper Control. The control circuit adopted multi-protect strategy which enhanced securityand stability of the power. Comparing with the traditional pulse power, it's provided withexcellent characteristics, such as sensitivity and stability, easy-control electric parameter, highpulse frequency and reducing volume and weight.At present, this electrical discharge surface hardening equipment has been used inLiYang aero-engine manufactory in GuiZhou province and runs well. The hardening coatingobtained by using this equipment is better. It provided reliable guarantee to resolve theabrasion of aero-engine turbine labyrinth teeth.