Formation of High Temperature Compounds in W-C-B System by Reactive Spark Plasma Sintering

The formation of high temperature composites in W-C-B system from fine-grained powders in dependence on the ratio of components by using reactive spark plasma sintering was studied. The mixture of W2C and C nanoparticles was used as tungsten and carbon precursors. The W2C and carbon mixture with different ratio of components was prepared by reduction of WO3 in presence of CH4 in nitrogen inductively coupled plasma. The specific surface area of the mixture was in the range of 36 - 42 m(2)/g in dependence on the content of carbon. The W2C and carbon particles were mixed mechanically with amorphous boron and densified using the spark plasma sintering technique at 1500 - 1700 degrees C and pressure of 30 MPa for 4 minutes. The sintered bodies contained WB2 and B4C phases. The ratio of phase depends on the content of the components in the raw mixture.