Relationship between electrical resistance and thermal expansion coefficient in YBCO and Ti67Al33

Abstract

Abstract Experimental study of thermal coefficients of both electrical resistance and volume expansion in nanostructured superconducting ceramics YBa2Cu3O7-8 and intermetallic Ti67Al33 alloy was performed. In both compounds we found a correlation between the temperature dependences of these coefficients. Formation and relaxation of charge excitations in conductors with a nonmetallic type of interatomic bonds are discussed. We point that, to explain temperature dependence of the conductivity, one should take into account an anharmonicity of atomic vibrations.