Flexible Ceramic Sheet Core for Turbine Blade Manufacturing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for manufacturing ceramic cores for turbine engine blades face challenges in reducing the trailing edge thickness without increasing fragility, as the cores are prone to cracking during baking and handling due to the viscosity issues of ceramic paste and the fragility of thin areas.
Innovation Solution
A method involving a flexible ceramic sheet is placed in a mold, where a ceramic paste frame is injected to co-sinter with the sheet, maintaining shape and reducing thickness while enhancing flexibility to prevent fissures, and recess patterns can be cut to create a network of cavities, using a combination of silica and alumina for the sheet and zircon for the paste.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Length of moving object
If the thickness of the trailing edge slot is reduced to improve aerodynamic performance, then the thickness of the blade trailing edge is reduced, but the ceramic core becomes more fragile and prone to cracking during manufacturing
Solution Approach 1:
The patent uses a flexible ceramic sheet instead of traditional rigid ceramic paste to form the core. This flexible sheet can be easily shaped and positioned in the mold, and its flexibility prevents cracking during handling and manufacturing processes, even when the core thickness is reduced to achieve thin trailing edges.
Solution Approach 2:
The patent combines a flexible ceramic sheet with a ceramic paste frame to create a composite core structure. The flexible sheet provides the thin, crack-resistant core body, while the ceramic paste frame provides structural support and maintains the desired shape during sintering, resolving the contradiction between thinness and fragility.
2Manufacturing precision
If traditional ceramic paste injection method is used to manufacture thin cores, then the core can be formed, but cracks appear during baking due to paste viscosity and re-attachment issues
Solution Approach 1:
The flexible ceramic sheet replaces the traditional ceramic paste for forming the thin core areas. This sheet can be precisely shaped to the desired thin thickness without the viscosity problems of paste, and it maintains its shape without re-attachment issues during the sintering process.
Solution Approach 2:
The patent changes the physical state and properties of the ceramic material from a viscous paste to a flexible sheet. This parameter change allows for precise thickness control and eliminates the re-attachment problems that occur when paste fronts meet during injection molding of thin sections.
3Ease of operation
If the ceramic sheet is made flexible to prevent fissures, then the sheet can be easily handled and shaped, but additional steps are required to maintain the shape during baking
Solution Approach 1:
The patent creates a composite structure where the flexible ceramic sheet is combined with a ceramic paste frame. The frame acts as a rigid support that maintains the sheet's shape during sintering, eliminating the need for additional shape-maintaining steps while preserving the flexibility benefits of the sheet.
Solution Approach 2:
The patent merges the flexible ceramic sheet with the ceramic paste frame in a single integrated core structure. This combination allows the sheet to provide flexibility and thin-section capability while the frame provides shape stability, eliminating the need for separate shape-maintaining operations.
4Manufacturing precision
If ceramic paste is used to form thin areas, then the core can be manufactured, but the paste has difficulty tolerating very fine thicknesses due to viscosity
Solution Approach 1:
The patent uses a flexible ceramic sheet instead of ceramic paste to form the thin areas of the core. The sheet can be manufactured with precise thin thicknesses and is easy to handle, cut, and shape, completely avoiding the viscosity-related handling difficulties of ceramic paste in thin sections.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This method allows for a thin core with reduced risk of fissures, maintaining shape without additional steps, enabling the production of blades with thin trailing edges while maintaining structural integrity and reducing manufacturing costs.
Implementation Method 1
baking by sintering the core obtained in the previous step
Implementation Method 2
drying the sheet obtained in the preceding step
Implementation Method 3
co-sintering the ceramic sheet and the frame so as to secure the ceramic sheet and the frame together
Data Source
AI summary
A method of manufacturing a core for molding a blade of a turbomachine, including placing a flexible ceramic sheet in a cavity of a mold in such a way as to shape the ceramic sheet, introducing a ceramic paste into the cavity of the mold, the ceramic paste forming at least one frame in contact with the ceramic sheet, and co-sintering the ceramic sheet and the frame in such a way as to rigidly join together the ceramic sheet and the frame, the frame maintaining the shape of the ceramic sheet given by the mold during the preceding co-sintering phases.