ELECTRICAL-RESISTIVITY OF TITANIUM DIBORIDE AND ZIRCONIUM DIBORIDE

The electrical resistivities of hot-pressed samples of Ti1-xZrxB2 (x = 0.0, 0.3, 0.5, 0.7, 1.0) were measured by a four-point ac technique over the range 298 to 1573 K in an argon atmosphere, The hot-pressed samples for the intermediate compositions were found to be mixtures of two solid-solution phases, The resistivities for all compositions were found to increase linearly with temperature and can be described by rho(T) = rho(298) + phi(T - 298), The room-temperature resistivity phi(298) (mu Omega.cm) and the temperature coefficient of resistivity phi (n Omega.cm/K) for ZrB2 were determined to be 7.8 and 10, both of which increase with the content of TIB2. These values for TIB2 were determined to be 20.4 and 36, respectively.