The current-voltage curves I-V for different temperatures and ambient pressure Figure 7 indicated that increasing temperature increased resistance higher slope value which is typical behaviour expected for a PTCR device i.e. they had ohmic behaviour within the measurement range used. The presence of intergranular porosity can be noted from observing the microstructures of the sintered sample using SEM Figure 7 and uniform grain size having spherical morphology; average grain size was ≈ 3.0679 μm. The average was obtained by analysing 50 data, using DMP 1000 ZView software. The porosity of the sintered sample presented may have been mainly generated by the presence of agglomerates in the powder.
Las curvas de corriente-voltaje curvas I-V para diferentes temperaturas y presión ambiental Figura 7, indican que al aumentar la temperatura se incrementa la resistencia mayor valor de su pendiente, el cual es el comportamiento típico esperado para un dispositivo PTCR; ellas presentan comportamiento óhmico dentro del rango de medida utilizado.