Silica-based ceramic core and preparation method thereof

Abstract

The invention discloses a silica-based ceramic core and a preparation method thereof. The silica-based ceramic core is prepared from the following raw materials in parts by weight: 60-67 parts of silica glass powder, 30 parts of zircon sand and 3-10 parts of a SiO2 additive agent, according to a setting proportion, the raw materials are weighed, mixed and dried, and an elasticizer is added and stirred; compression moulding and demoulding of mixed slurry are conducted, a green body is obtained, and a compressed green body sample is embedded into calcination alpha-type aluminium oxide filler; and according to a set heating rate, the temperature rises for sintering, finally, the sintered sample is put into an ethyl silicate strengthening solution, after still standing, natural drying is conducted, and the core is obtained. According to the silica-based ceramic core and the preparation method thereof, sintering shrinkage of the silica-based ceramic core is low, high temperature bending strength is good, size control is good, the surface is smooth, during metal pouring, core-separating is easy, and abreuvage cannot be formed on the interfaces of metal and the core.

Description

technical field

[0001] The invention relates to the field of silicon-based ceramic cores, in particular to a silicon-based ceramic core and a preparation method thereof. Background technique

[0002] Modern aero-engines are developing towards a high propulsion ratio, and the most effective way to increase the thrust-to-weight ratio of the engine is to increase the temperature at the front inlet of the turbine, which puts forward higher requirements for the high-temperature resistance of the turbine blades. From the perspective of the material itself, the use of alloying to improve the temperature bearing capacity of the material is currently approaching the limit, and the difference in thermal expansion coefficient also limits the application of high-temperature protective coating materials on blades.

[0003] With the development of advanced air-cooling technology, the shape of the inner cavity of the blade is becoming more and more complex. It is difficult to implement con...

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