Aluminium-doped perovskite phase negative temperature coefficient thermal sensitive ceramic material

Abstract

The invention relates to an aluminium-doped perovskite phase negative temperature coefficient thermal sensitive ceramic material. The aluminium-doped perovskite phase negative temperature coefficient thermal sensitive ceramic material is prepared from La2O3, MnO2 and Al2O3 by steps of preparing a perovskite phase LaMn1-xAlxO3 powder material by adopting an oxide solid-phase method, then doping Al2O3, forming and sintering at a high temperature. The electrical parameter range of the aluminium-doped perovskite phase negative temperature coefficient thermal sensitive ceramic material is B25 / 501817-3920K+ / 2%, rho25 DEG C 4.7-6.13*10<6>omega.cm+ / -3%. The aluminium-doped perovskite phase negative temperature coefficient thermal sensitive ceramic material has the advantages of wide adjustment range of electrical parameter and high repeatability. The aluminium-doped perovskite phase negative temperature coefficient thermal sensitive ceramic material is simple in a preparation technology and convenient to operate. The material formulation can be flexibly selected in a wide range according to the need. The aluminium-doped perovskite phase negative temperature coefficient thermal sensitive ceramic material is applied to thermistor elements for temperature measurement, control compensation and the like under different conditions.

Description

technical field

[0001] The invention relates to an aluminum-doped perovskite phase negative temperature coefficient thermosensitive ceramic material. Background technique

[0002] Negative temperature coefficient (NTC) thermistors are widely used in temperature measurement, control, compensation, and suppression of inrush current due to their high measurement sensitivity, good interchangeability, and high reliability. Traditional thermistors are made of spinel-structured MMn 2 o 4 Oxide composition, where M is transition metal elements such as Ni, Co, Fe, Cu, Zn. In general, such ceramic materials with a single spinel structure exhibit certain limitations. On the one hand, the aging phenomenon is obvious, so that its application is limited to a temperature of 300 ° C; on the other hand, its resistivity and thermal constant B The value is positively correlated, that is, when the resistivity is high, B value is also higher, and vice versa. The development of modern scien...