Preparation method of zirconia hollow sphere heat insulation product for tungsten-molybdenum sintered intermediate frequency furnace

Abstract

The invention belongs to the technical field of fireproof materials, and particularly relates to a preparation method of a zirconium oxide hollow sphere heat-insulating product for a tungsten-molybdenum sintering medium-frequency furnace. The preparation method comprises the following steps of: taking a zirconium oxide hollow sphere as an aggregate, and adding electric melting zirconium oxide powder and zirconium oxide micropowder prepared through a chemical method; taking a water-soluble epoxy resin solution or a water-soluble alkyd resin solution as a bonding agent, and blending, forming and drying to serve as a liner of the tungsten-molybdenum sintering medium-frequency furnace; firstly using for the tungsten-molybdenum sintering medium-frequency furnace. The preparation method disclosed by the invention can be used for improving the thermal shock resistant property of the product and enhancing the compression strength by utilizing the characteristics of a production process of the tungsten-molybdenum sintering medium-frequency furnace, combining with high bonding strength of water-soluble epoxy resin or water-soluble alkyd resin under hydrogen or inert gas at medium and low temperature and keeping the transformation toughening effect of the zirconium oxide micropowder prepared through the chemical method, thereby prolonging the service life of the liner of the tungsten-molybdenum sintering medium-frequency furnace.

Description

technical field [0001] The invention belongs to the technical field of refractory materials, and in particular relates to a preparation method of a zirconia hollow spherical heat insulation product used in a tungsten-molybdenum sintered intermediate frequency furnace. Background technique [0002] Zirconia hollow sphere heat insulation products are usually used as the inner lining of tungsten-molybdenum sintered intermediate frequency furnace. The tungsten-molybdenum sintering intermediate frequency furnace is an intermittent gas-shielded furnace with a complex furnace structure and large lining bricks. The operating temperature is above 2000°C. The production cycle of the tungsten-molybdenum sintering process is short and the temperature rises and falls frequently. It is required that the zirconia hollow sphere heat insulation products have good thermal shock resistance and can withstand severe temperature fluctuations; at the same time, they have high compressive strength ...

AI Technical Summary

Problems solved by technology

[0003] Traditional zirconia hollow sphere insulation products use zirconia hollow spheres as aggregates, fused zirconia powder with a particle size of <0.044 mm as the matrix, and calcium lignosulfonate solution as the binder. It is fired in a shuttle kiln at 1700-1800°C for 6-10 hours, with long production cycle and high energy consumption

Limited by the shuttle kiln, the maximum firing temperature of the shuttle kiln is only 1800 °C. The firing temperature of 1800 °C results in a low room temperature compressive strength of zirconia hollow sphere insulation products, which is only about 20 MPa; Calcium solution is used as a binder, and the low-temperature bonding strength of calcium lignosulfonate in the production process is poor, so it needs to be fired at a slow speed in a shuttle kiln. At the same time, calcium lignosulfonate is brought into calcium oxide, causing zirconia Hollow ball heat insulation products have poor thermal shock resistance, and the number of furnaces used is only about 5 times, which cannot meet the service life of the lining of tungsten-molybdenum sintered intermediate frequency furnace