Liquid phase sintering method of Si3N4-TiZrN2-TiN composite conductive ceramic

Abstract

Provided is Si3N4-TiZrN2-TiN composite conductive ceramic. Raw materials for synthesizing the composite conductive ceramic comprise Si3N4, ZrN, TiN, Y2O3, La2O3 and AlN. The final product of the composite conductive ceramic comprises an Si3N4 phase, a TiN phase and a solid solution TiZrN2 phase of metal nitride. Due to addition of AlN, volatilization caused by adding of Al2O3 in a conventional mode is avoided, and the surface of the final product to which AlN is added can be smoother than that of the product to which Al2O3 is added. The invention further provides a liquid phase sintering method of the Si3N4-TiZrN2-TiN composite conductive ceramic. The Si3N4-TiZrN2-TiN composite conductive ceramic has the advantages that electrical resistance is low, wherein the sample resistance tested by an SX1944 four-probe tester for the composite conductive ceramic is at the 10-2 omega.cm order which is far lower than that of like products; the mechanical strength is high, wherein the load of the composite conductive ceramic is 10 kg, the pressurizing time is 5 s, the measured Vickers hardness of the sample is 14.7 GPa, the sample breaking tenacity calculated through the hardness indentation quadrangle expansion crack length is 7.8 MPa.m 0.5, and the original strength and hardness of silicon nitride ceramic are kept.

Description

Technical field:

[0001] The invention relates to the technical field of conductive ceramics, in particular to a Si 3 N 4 -TiZrN 2 -Liquid phase sintering method of TiN composite conductive ceramics. Background technique:

[0002] Silicon nitride (Si 3 N 4 ) is a structural ceramic material with good performance, which has light weight, high strength, high hardness, high corrosion resistance, etc., and can be used in various industries. There are many ways to prepare silicon nitride ceramic materials, such as hot pressing, normal pressure, reaction and other sintering methods, among which the normal pressure sintering method is simple and easy, and consumes less energy. Since silicon nitride is a covalent bond compound with a low self-diffusion coefficient, it is difficult to sinter directly into porcelain, so some oxides are often added as sintering aids for sintering. Commonly used are Al 2 o 3 , Y 2 o 3 , MgO 2 Wait. These additives form a liquid phase during t...