Future Prospects and Fields of Application

The poor corrosion resistance of borides may be partially overcome in composites with SiC if the microstructure allows passive oxidation kinetics. In combination with SiC the borides retain their high electrical and thermal conductivity and thus suitable thermal shock resistance. SiC-TiB2 composites have been extensively developed for wear parts in machinery such as sliding rings, valves, valve seats, roller and ball bearings, plungers, and rocker arm pads. 

Besides the well-known cemented carbides and cermet cutting tools, boron carbide- and titanium diboride-containing cermets have been proven suitable for 

Although mechanical applications are currently by far the most important aims for the development of materials and parts based on carbides and borides, this may easily change to the benefit of thermal and electrical applications if there is an improvement in the understanding and control of the semiconductivity of B4C and a breakthrough in the manufacture of suitable parts. Moreover, thermal applications may increase considerably in importance as more efficient energy conversion or recovery becomes a significant requirement. 

Functional applications of borides are also related to the high cross-section of boron for the absorption or retardation of thermal neutrons. B4C sintered products have been used as moderating elements and radiation-protecting components in nuclear reactors of several designs. Of course, this market is declining with the decreasing political support for nuclear power and nuclear research. 

In conclusion, boride ceramics are materials of high potential for use in mechanical and electric fields. Due to the stagnating materials markets, however, most research on borides is focused on the basic questions of atomic bonding and physical transport properties rather than on application-related problems. Only a few highly specialized research groups are active worldwide and promote the science rather than the technology of borides. Depending upon the economic situation and the 

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