Silicon carbide-calcium hexaluminate-aluminum composite refractory material

Abstract

The invention belongs to the field of refractory materials, and relates to a silicon carbide-calcium hexaluminate-aluminum composite refractory material. According to the silicon carbide-calcium hexaluminate-aluminum composite refractory material, silicon carbide particles with the adding amount being 60%-75% of the total mass of raw materials serve as aggregate; a matrix is also added into the composite refractory material, wherein the matrix contains compact calcium hexaluminate fine powder or micro powder; and metal aluminum powder subjected to coating treatment is further added into the matrix, the particle size range is 10-45 microns, and the adding amount is 2%-8% of the total mass of the raw materials. By uniformly mixing the aggregate, the matrix and the binding agent, carrying outmechanical pressing molding, drying, and sintering at the highest temperature of 1500-1600 DEG C in a carbon-buried atmosphere, the silicon carbide-calcium hexaluminate-aluminum composite material isobtained. According to the invention, the phase composition of the matrix is improved, the high-temperature mechanical property and the high-temperature breaking strength of the material are improved, and meanwhile, the material has the characteristics of excellent erosion resistance, low price, excellent thermal shock resistance and the like.

Description

technical field [0001] The invention belongs to the field of refractory materials, and mainly relates to a silicon carbide-calcium hexaaluminate-aluminum composite refractory material. Background technique [0002] In the field of contemporary coal gasification, the most widely used gasification technology is coal water slurry gasification technology, which utilizes the combustion of coal water slurry under high temperature and high pressure environment to prepare H 2 , CO, CO 2 Wait for gas. The operating conditions of the coal-water slurry gasification furnace designed based on the coal-water slurry gasification technology are: 1300℃~1500℃ high temperature, 2.0~8.5MPa high pressure and strong reducing atmosphere. During the operation of the gasifier, it is also accompanied by high-speed airflow, Scouring and impact of slag and solid matter on the lining material. The pressure in the furnace and the continuous erosion of gas, liquid and solid substances in the high tempe...

AI Technical Summary

Problems solved by technology

This silicon carbide-calcium hexaaluminate-aluminum composite refractory material has excellent slag resistance, but poor high-temperature mechanical properties (high-temperature flexural strength is about 2-4MPa, buried carbon for 30min at 1400°C), facing coal-water slurry gas The high temperature and high pressure of the chemical furnace and the continuous erosion of gas, liquid and solid are very prone to material wear and peeling.

The main reason for its low high-temperature mechanical strength is that although a buried carbon atmosphere or a protective atmosphere is used, SiC will still be oxidized during the firing process to form SiO 2 Into the matrix, forming a low-melting point glass phase, the glass phase changes from a solid phase to a liquid phase at high temperature, destroying the stability of the matrix structure, resulting in low high-temperature strength

Images