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The method of infiltration is to press tungsten powder into a blank, preburn it at a certain temperature to prepare porous tungsten matrix skeleton with a certain density and strength, and then melt the metal copper with a lower melting point into the tungsten skeleton, so as to obtain a denser tungsten-copper material. The main mechanism is that when the liquid metal moistens the porous matrix, the liquid metal flows along the particle gap under the capillary force to fill the porous tungsten skeleton pores, so as to obtain relatively dense materials. This method can improve the toughness of tungsten copper. The high-density tungsten-copper composite prepared by the method of infiltration has good thermal and electrical conductivity, but it is difficult to achieve full connection and uniform size of the pores of the tungsten skeleton, and it is difficult to guarantee the uniformity of copper distribution of the product after infiltration, which is bound to affect the material performance. With the development of powder plasticizing near net forming technology and the increasing requirement of modern science and technology on the shape complexity of parts, the preparation of tungsten skeleton has developed from traditional powder metallurgy die pressing to extrusion and injection molding. As American RM German preparation tungsten skeleton using injection molding technology, obtained the good effect, they will be in advance of the preparation of tungsten skeleton by 900 ℃ presintering, 9 o ~ 120 min at 1500 ℃ melt infiltration, the alloy obtained good performance. The tungsten - copper composites prepared by this method are widely used because of their excellent properties. However, this method also has a lot of shortcomings, especially in the need for machining to remove the excess copper after melting and seepage, which increases the processing cost of post-processing and reduces the yield rate, and is not conducive to the adoption of parts with complex shapes.
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