Tungsten Copper Infiltration

Tungsten copper infiltration: Under the action of capillary force, the liquid flows along the particle gap when the metal liquid wetting porous matrix, thus filling the porous W skeleton pores in order to obtain a more dense material. The toughness of tungsten copper alloy can be improved by this method.

Tungsten copper infiltration can be divided into high temperature sintered tungsten skeleton and low temperature sintered partially mixed powder. High temperature sintering of tungsten skeleton after copper infiltration, then sintered in high temperature hydrogen to form the skeleton, sintered tungsten in a vacuum or in a protective atmosphere above the melting point of copper. Under the action of a capillary, molten copper is infiltrated into the tungsten skeleton. Thus, the tungsten copper with relative density of more than 99.2% was developed. The sintered tungsten skeleton is suitable for the preparation of the vacuum tungsten copper with low copper content. This method can obtain higher strength of the skeleton, making the material more resistant to arc burning, the reduction of tungsten powder is more sufficient, and the low melting point impurity can be removed by volatilization and thermal decomposition. At present, this method has been used in the production of large and medium sized high voltage circuit breakers and vacuum switches.

 

In general, the infiltration of the liquid phase of the copper is only in the tungsten skeleton pore capillary infiltration, densification rate is slow and low. There are some difficult problems in this method, for example, it can not be used to produce Cu content of low and complex shape of tungsten copper element. Due to the harsh requirements of sintering conditions, this method has great limitations in the industrial application.

 

WeChat