PROPERTIES OF NEW TiC/TiB_2/Fe-Al CERMET ALLOY

摘要

Effect of TiB_2 substitution on thermal conductivity and hardness in TiC/Fe-Al cermets was investigated. The (70-x)TiC/xTiB_2/26Fe-4Al mass% cermets were fabricated by mechanical milling and subsequent pulsed current sintering method. The high relative density compacts was formed by sintering at 1423 K under 25 MPa for 60 s. The sintered materials were mainly composed of TiC, TiB_2 and Fe-Al intermetallic compound. In addition, small amounts of Fe_2B surrounding TiB_2 were formed. The thermal conductivity of the sintered compact lineally increased with increasing TiB_2 volume fraction. However, the hardness of the sintered compacts of x = 20 - 40 were higher than that of x = 0. Therefore, the substitution of TiC to TiB_2 in the TiC/Fe-Al based cermet is effective to improve the thermal conductivity without the degradation of hardness.