Tapered embedded locating method for silicon-based ceramic core and aluminium-based ceramic shell

Abstract

The invention relates to a tapered embedded locating method for a silicon-based ceramic core and an aluminium-based ceramic shell. The method comprises requirements as follows: 1) locating grooves are designed on locating surfaces of the ceramic core, wherein when one groove is used, a quadrate-tapered groove is selected, and when two locating grooves are used, the two locating grooves are tapered grooves; 2) a wax member, in a wax mould design, is provided with locating holes corresponding to the locating grooves; and 3) a small-planar locating mode is selected for other assistant locating; a weak area, where blade exhausting slots are located, is provided with a free end; and the thickness of the free end is 0.1 mm-0.5 mm. The locating method provided by the invention is advantageous in that the ceramic core is stably located in the ceramic shell; enough space is provided for expansion and contraction when the ceramic core is subjected to high temperature phase transitions; metallurgical defects, which are caused by locating problems of silicon-based ceramic cores and aluminium-based ceramic shells, such as out-of-tolerance blade sizes, slant blades, leak blades, broken cores, and the like are prevented; operation is simple and reliable; additional cost is very low; and the product qualified rate increases from 20% to 90%.

Description

technical field [0001] The invention relates to the technical field of single-crystal (orientation) hollow turbine blades without margin in the investment casting method, and in particular provides a conical embedded positioning method for a silicon-based ceramic core and an aluminum-based ceramic shell. Background technique [0002] The performance requirements of new aero-engines for their turbine blades are getting higher and higher. As a result, the design and structure of turbine blades, one of the most critical components of engine thermal breaks, are becoming more and more complex, and the requirements for manufacturing processes are getting higher and higher. Hollow cores with complex air-cooling structures , the characteristics of no margin, and the turbine blades using directional and single-crystal placement processes have become the mainstream in the design of new engines, and have been widely used in developed countries. In recent years, extensive and in-depth re...

AI Technical Summary

Problems solved by technology

Its new method of specific silicon-based ceramic core and aluminum-based ceramic shell solves the problem of shrinkage of the two materials due to the long-term work of the silicon-based ceramic core and aluminum-based ceramic shell at a high temperature of 1500 ° C to 1600 ° C. Inconsistency leads to blade size out-of-tolerance and blade deflection, leakage, and broken core problems

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