Tungsten Copper Electrode Infiltration Process

Tungsten copper electrode production process as follow:
1. Preparation: Firstly, put tungsten powder, induced copper powder in ball grinding mill, and add 1% of stearate and dried and sieved to thereby obtain mixed powder after a while.

2. Compacting: Hydraulic machine pressing, we should concern the weighing in case of the loss of powder loss during the compacting process,

3. Degreasing: Using H₂ as protective atmosphere when thermal degreasing, adhesive must be removed in order to avoid contamination and clean sintering furnace.

4. Sintering: Sintering in molybdenum wire furnace, H₂ as protective atmosphere.

5. Infiltration: Using H₂ as protective atmosphere and infiltrated copper at 1200-1300℃.

6. After-processing: The infiltrated tungsten copper alloy electrode after annealing treatment to improve the performance of the alloy, and then subjected to a surface treatment to remove excess copper.

In the process of tungsten copper, silver-tungsten, ferro tungsten mechanical parts and metal-ceramic materials, the infiltration method is one of the most major processes. Take tungsten copper electrodes for example, the infiltration process is immerse tungsten skeleton in liquid copper after high temperature sintered, so that the pores are filled with liquid copper, then by annealing and cooling to obtain a dense tungsten copper materials.

Thus, infiltration process is the preparation of tungsten-copper electrode in the most critical a process, which directly affects the overall performance of tungsten copper electrodes. However, the most of present study concentrated on the parameters of infiltration, for infiltration mechanism is quite few, and most of these studies are directed to coarse particles of tungsten powder, and rarely comes to fine particles of tungsten powder. Infiltration is the process relies on an external metal powder wetted porous body (tungsten skeleton), under the action of capillary force, the liquid metal (Cu) along the inter-particle porosity within the particle porosity flow or until completely filled up the pores.