Titanium metal powder injection molding micro gear, turbine

Titanium metal powder injection molding micro gear, turbine

Method for surface modification of titanium alloy gear

A method for preparing a strong and tough molybdenum gradient modified layer on the surface of a titanium alloy gear. The molybdenum gradient modified layer prepared by the method has a large thickness, high hardness, good wear resistance and strong load-bearing capacity.

The present invention provides a method for preparing a strong and tough molybdenum gradient modified layer on the surface of a titanium alloy gear. The plasma surface alloying method is adopted, with a molybdenum target as the source electrode and a titanium alloy gear as the workpiece electrode. After deposition and diffusion, a strong and tough molybdenum gradient modified layer is formed on the surface of the titanium alloy gear.

The method for preparing a strong and tough molybdenum gradient modified layer on the surface of the titanium alloy gear mentioned above specifically includes the following steps:

(1) Pre-sputtering treatment of the titanium alloy gear surface: Put the gasoline-cleaned titanium alloy gear on the workpiece table in the plasma surface alloying furnace, evacuate to vacuum (0.1 Pa), introduce high-purity argon gas, and control the gas pressure at 30 ~ 40 Pa. Pre-sputter the gear surface by adjusting the workpiece electrode voltage (first adjust to -300 V, then gradually adjust to -900 V) to clean the stains and passivation layer. After cleaning for 40 to 50 minutes, turn off the power supply and gas, and evacuate to 0.1 Pa vacuum state again;

(2) Heating: Continue to introduce argon gas into the plasma surface alloying furnace to 30 ~ 40 Pa; turn on the circulating water and temperature meter in sequence; turn on the source electrode and workpiece electrode power supply, keep the source electrode and workpiece electrode at the same potential, and heat the workpiece to 900 ~ 950 °C; control the source electrode bias voltage at -600 ~ -900 V, the workpiece bias voltage is controlled at -350 ~ -650 V, and the workpiece temperature is adjusted to 800 ~ 900 °C; the duty cycle and frequency of the workpiece power supply are adjusted to the maximum value to facilitate temperature control;

(3) Insulation: While keeping the voltage difference between the source and the workpiece unchanged, the temperature of the workpiece is controlled at 800 ~ 900 °C by adjusting the duty cycle and frequency for 3 ~ 5 hours, so that the argon ions bombard the source and sputter the molybdenum ions, and the atoms and particle clusters are deposited and diffused on the surface of the titanium alloy gear to form a molybdenum gradient modified layer;

(4) Cooling: Turn off the source and workpiece power supplies in turn to slowly cool the workpiece to room temperature.

In the above method, the speed of gradually adjusting the workpiece pole voltage in step (1) is 100 V/min;

In the above method, the purity of the molybdenum target is ≥ 99.97%, and the purity of the argon gas is 99.999%;

In the above method, the gradient modified layer comprises a molybdenum deposition layer and a molybdenum diffusion layer, and the molybdenum deposition layer, the molybdenum diffusion layer and the titanium alloy gear substrate are metallurgically bonded and have no obvious interface.

In the above method, the pressure difference between the source bias and the workpiece pole bias is kept constant, and the obtained modified layer is uniform. Preferably, the pressure difference is controlled at 200 ~ 250 V.

Qinhuangdao Zhongwei Precision Machinery Co., Ltd. is a high-tech enterprise focusing on metal powder injection molding (MIM) and investment casting and forging research and development, production and service, with a complete production system of design-mold opening-batch-sintering-machining-grinding-assembly. Focus on titanium alloy, high temperature alloy, stainless steel, iron-based products

Our company can produce various complex three-dimensional structural parts, functional parts, and appearance parts according to the needs of different customers. Our products are widely used in 3C, lock industry, watch and jewelry industry, medical device industry, home appliance industry, automobile industry, communication product industry, etc. Based on a team of talented people who graduated from the Department of Powder Materials, we provide high-quality products to customers in various industries through rigorous and standardized management and control processes.