Experimental and theoretical study on the resistive properties of LaCo0·4Ni0·6O3 ceramic with Mg-ion substitution

Abstract

To explore an air-fireable and economically functional phase for thick-film resistors, the crystal structure, microstructure, sintering, and resistive properties of LaCo0·4Ni0.6−xMgxO3 (LCNM, x = 0.00–0.08) ceramics are studied in this paper, based on solid-state reaction experiments and theoretical calculations. With Mg-ion increase, the impurity phases of NiO and La3Ni4O10 increased, the maximum shrinkage rate occurred at a higher temperature, and the microstructures became worse. The addition of the Mg ion increased the resistivity and decreased the temperature coefficient of resistivity (TCρ). The calculation results, including the bond population, electron density distribution, and density of states of the system agreed with the change in experimental resistivity. Relatively low resistivity and TCρ with a small absolute value could be achieved for specimens with x ≤ 0.02 sintered at 1200 °C and 1250 °C. Hence, the LCNM (x ≤ 0.02) ceramics are possible functional material for thick-film resistors.