Patent ID: 9159477
Filing Date: 2015-10-13
Classification: H01C,Y10T

Abstract:
1. A method for preparing a laminated chip composite resistor combining a thermistor and a varistor, comprising the steps of: (1) generating green sheets of a thermistor and green sheets of a varistor using formulation powders of a thermistor and a varistor respectively via a tape casting method, in which said formulation powder of a varistor is obtained by: adding an oxide of manganese (Mn) and an oxide of cobalt (Co) into a mixture of zinc oxide (ZnO) and bismuth oxide (Bi said formulation powder of a thermistor is obtained by: mixing nano or sub-micron barium titanate (BaTiO (2) mixing said formulation powder of the thermistor with that of the varistor according to a mass ratio of 1:2 to 2:1, ball-milling the mixture so that it is uniformly mixed, performing tape casting on the mixed powder thereby obtaining a green sheet with a thickness of 20 μm to 60 μm which operates as a green sheet of a transition layer; (3) alternately laminating said green sheets of the varistor and nickel (Ni) electrodes, overlying said green sheet of the transition layer thereon, alternately laminating said green sheets of the thermistor and nickel (Ni) electrodes on said green sheet of the transition layer, performing hot isostatic pressing thereon, and cutting an obtained green sheet to a desired size according to electrode patterns thereof; (4) processing said resistor in air at temperature below 500° C. after cutting; (5) sintering said processed resistor in a protective atmosphere at temperature of 850° C. to 1150° C., performing heat treatment thereon in oxygen or air at temperature of 500° C. to 800° C., coating an Ag electrode thereon, and burning said Ag electrode.