High-Temperature Glass Gasket Compositions for Sealing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current glass compositions for high-temperature gaskets in electrolyzers and fuel cells face challenges such as inadequate mechanical and chemical resistance, high temperature corrosion, and complex heat treatment requirements, making them unsuitable for maintaining seals under varying thermal expansion coefficients and pressure differences.
Innovation Solution
A glass composition comprising 70-76% SiO2, 7-8% B2O3, 5-6% Al2O3, and 10-17% Na2O, or 63-76% SiO2, 5-12% ZrO2, 0-12% B2O3, 0-2% La2O3, and 11-14% Na2O, with a low crystalline phase content, providing a visco-plastic state for flexibility and rigidity, and low interaction with materials, ensuring stability and resistance over time.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional glass compositions are used for high-temperature gaskets, then sealing function is provided, but mechanical and chemical resistance is inadequate and high temperature corrosion occurs
Solution Approach 1:
The patent modifies the chemical composition parameters of the glass by incorporating specific amounts of Al2O3 (5-17 mol%), B2O3 (3-15 mol%), and Na2O (8-20 mol%), along with optional additives like ZrO2, La2O3, and TiO2. These parameter changes enhance the mechanical strength and chemical resistance while maintaining sealing reliability at high temperatures up to 1000°C
Solution Approach 2:
The invention creates a composite glass material combining multiple oxide components (SiO2, Al2O3, B2O3, Na2O) with controlled crystalline phase content (0-50%). This composite structure provides both the sealing properties of glass and the enhanced mechanical/chemical resistance of controlled crystallization, resolving the contradiction between sealing reliability and strength
2Strength
If complex heat treatment is applied to glass gaskets, then mechanical properties are improved, but manufacturing complexity increases
Solution Approach 1:
The desired crystalline phase structure is built into the glass composition during initial manufacturing, with pre-selected oxide ratios and controlled cooling rates that promote spontaneous formation of beneficial crystalline phases (0-50% content) during service. This preliminary design eliminates the need for complex post-manufacturing heat treatment cycles, reducing manufacturing complexity while maintaining mechanical properties
Solution Approach 2:
The glass composition is designed to undergo controlled crystallization automatically during normal service conditions (temperature cycling and aging), with the material self-adjusting its internal structure to develop optimal mechanical properties. This self-service crystallization process eliminates the need for external heat treatment interventions, simplifying manufacturing
3Reliability
If glass gaskets are used in high temperature applications, then sealing is provided, but thermal expansion mismatch causes stress and potential cracking
Solution Approach 1:
The patent adjusts the thermal expansion characteristics by modifying the glass composition, particularly the ratios of network formers (SiO2, B2O3) and modifiers (Na2O, Al2O3). This parameter optimization enables the glass to achieve a thermal expansion coefficient that matches adjacent components (metals, ceramics), reducing thermal stress and preventing cracking while maintaining sealing reliability at temperatures up to 1000°C
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
The glass compositions maintain a glassy state at high temperatures, offering optimal balance between flexibility and rigidity, and exhibit low interaction with materials, ensuring reliable and long-lasting seals in high-temperature applications without complex heat cycles or crystallization, thus addressing the limitations of prior art.
Implementation Method 1
The glass compositions maintain a glassy state at high temperatures, offering optimal balance between flexibility and rigidity
Implementation Method 2
providing a visco-plastic state for flexibility and rigidity
Data Source
AI summary
A glass composition, characterized in that it is selected from the group consisting of: a glass composition (A) with the following molar percentages: 70 to 76% of SiO2, 7 to 8% of B2O3, 5 to 6% of Al2O3, and 10 to 17% of Na2O; and a glass composition (B) with the following molar percentages: 63 to 76% of SiO2, 5 to 12% of ZrO2, 0 to 12% of B2O3, 0 to 2% of La2O3, 11 to 14% of Na2O, and 3 to 5% of K2O. The glass composition can be used in a method for assembling parts, in particular for a method of manufacturing high-temperature electrolyzers (HTEs) or high-temperature fuel cells (SOFCs).