Borosilicate IGU Glass Plies for Thermal Shock Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional soda-lime glass plies used in automotive laminates are susceptible to thermal shock and cracking from impacts, limiting their effectiveness as thicker outer glass plies.
Innovation Solution
A borosilicate glass composition with a high SiO2, B2O3, and Al2O3 content, capable of fusion forming at high viscosities, is used to create glass plies that are resistant to thermal shock and cracking, suitable for use as outer plies in laminates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If soda-lime glass is used as a thicker outer glass ply, then the glass can be formed at lower costs and with simpler processing, but the glass is susceptible to thermal shock and cracking upon impact
Solution Approach 1:
The patent changes the chemical composition parameters of the glass by incorporating borosilicate glass with specific oxide ratios (SiO2: 70-80 wt%, B2O3: 10-20 wt%, Al2O3: 5-15 wt%). This compositional parameter change enables the glass to achieve both manufacturability and enhanced resistance to thermal shock and impact cracking, resolving the contradiction between ease of manufacture and reliability.
Solution Approach 2:
The patent creates a composite glass material by combining multiple oxide components (silica, boron oxide, aluminum oxide, and controlled amounts of alkali and alkaline earth oxides) to form a borosilicate glass composition. This composite material structure provides both the manufacturability of conventional glass and the enhanced thermal and impact resistance required for reliable automotive glazing applications.
2Reliability
If borosilicate glass composition is used to improve resistance to thermal shock and cracking, then the glass ply exhibits enhanced durability, but the liquidus viscosity increases making fusion forming more difficult
Solution Approach 1:
The patent carefully controls the composition parameters within specific ranges (SiO2: 70-80 wt%, B2O3: 10-20 wt%, Al2O3: 5-15 wt%, with liquidus viscosity of 500-2000 kP and T200P of 1700-1750°C). These parameter optimizations balance the conflicting requirements: sufficient viscosity for structural integrity and thermal resistance, while maintaining low enough melting temperature for feasible fusion forming processes.
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 borosilicate glass plies exhibit enhanced resistance to thermal shock and cracking, maintaining structural integrity and performance in automotive glazing applications.
Implementation Method 1
the borosilicate glass composition has a liquidus viscosity of greater than 500 kP
Implementation Method 2
the borosilicate glass plies exhibit enhanced resistance to thermal shock and cracking
Data Source
AI summary
Various aspects of insulating glass units (an IGU) are provided, where an IGU includes: a first glass layer; a second glass layer; a third glass layer between the first and second glass layers; a first scaled gap space between the first and the third layer; and a second sealed gap space between the second and the third glass layer; wherein at least one glass layers comprises: a borosilicate glass composition, comprising: at least 75 mol % SiO2; at least 10 mol % B2O3; and Al2O; in an amount such that sum of SiO2, B2O3, and Al2O3 is at least 90 mol %.