Alumina ceramics composite containing novel four-component sintering adjuvant

Abstract

The invention discloses an alumina ceramics composite containing a novel four-component sintering adjuvant, which is characterized in that the four-component adjuvant is MO-CaO-SiO2-L2O3, wherein M is one of Mg, Ba and Be, and L is a rare earth element which is one of Ce, La and Lu. The alumina ceramics composite has the following components in percentage by weight: (1), 75%-90% of alumina powder; (2), 3%-6% of nano MO (M is one of Mg, Ba and Be); (3), 2%-6% of nano SiO2; (4), 2%-6% of nano CaO; and (5), 3%-7% of nano L2O3 (L is the rare earth element which is one of Ce, La and Lu). The particle size of the four-component sintering adjuvant is less than 300 nanometers, and the particle size of main alumina powder is at nanometer scale, namely 1-10 nanometers. By forming liquid phase and gradually forming spinel-like matter (the melting point thereof is more than 2100 DEG C) at later sintering stage to eliminate the liquid phase, sintering is promoted and simultaneously the growth of grain is inhibited, air hole elimination is promoted, density is improved and fine and even alumina ceramics grain and grain boundary air hole are formed, thereby ensuring the alumina ceramics material to have better high-temperature mechanical performance and wear resistance.

Description

technical field [0001] The invention relates to a method for producing alumina ceramics, in particular to an alumina ceramic composition containing a sintering aid. Background technique [0002] Alumina ceramics have many advantages such as stable chemical properties, high mechanical strength, high hardness, high temperature resistance, good wear resistance, high electrical insulation capacity, oxidation resistance, good mechanical properties, rich raw material reserves, and low prices. It is an application field High-performance multi-purpose engineering ceramics with the widest usage, the largest amount, and great application development potential, widely used in various fields such as mechanical chemistry, electronics, aviation, and national defense [E. Medvedovski, Wear-resistant engineering ceramics, Wear, 249, 2001, 821 -828; Boutin P., Arthroplastie Totale de Hance par Prosthes en Alumine Fritte, Rev. Chir. Orthop., 1972, 58: 229-246.], known as the "King of Ceramics"...

AI Technical Summary

Problems solved by technology

However, liquid phase sintering also has many disadvantages. First, the liquid phase remains in the grain boundary as a glass phase, which reduces the high-temperature strength and wear resistance, and cannot meet certain high-temperature applications; secondly, it is easy to cause grain Abnormal growth [Edited by Suzuki Hiroshige, translated by Chen Shixing, Engineering Ceramics, Beijing: Science Press, 1989.] and hindering the further improvement of performance

Therefore, it is not enough to form small and uniform ceramic grains simply by forming a eutectic liquid phase to promote mass transfer and reduce the sintering temperature.