AZO-Gold Multilayer Coating for Aircraft Canopy Durability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Modern aircraft canopies face challenges with existing coatings that lack durability and functionality, particularly in providing effective radar attenuation and anti-static properties while maintaining transparency and resistance to environmental degradation.
Innovation Solution
A coated transparency with an electrically conductive multilayer stack comprising a first metal oxide layer of aluminum doped zinc oxide (AZO), a gold metal layer, and a second AZO layer, which provides low sheet resistance, high transmittance, and improved corrosion resistance, eliminating the need for additional protective organic layers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a silver layer is used to provide high electrical conductivity, then electrical conductivity is improved, but corrosion resistance deteriorates
Solution Approach 1:
The patent uses a composite multilayer structure consisting of AZO (aluminum-doped zinc oxide) and gold layers. The AZO provides corrosion resistance while the gold layer provides electrical conductivity. This composite approach combines the advantages of both materials to achieve both high electrical conductivity and corrosion resistance simultaneously.
Solution Approach 2:
Different layers in the coating serve different local functions: the AZO layer specifically addresses corrosion resistance, while the gold layer specifically addresses electrical conductivity. Each layer is optimized for its particular function, and the combination achieves both requirements.
2Object-affected harmful factors
If anti-reflective metal oxide coatings are applied at reduced temperatures to protect silver, then corrosion resistance is improved, but tensile elongation property deteriorates
Solution Approach 1:
The patent changes the material composition parameter from traditional ITO to AZO (aluminum-doped zinc oxide), which has different physical and chemical properties. AZO maintains corrosion resistance while providing improved flexibility and tensile elongation, allowing the coating to withstand thermal and mechanical stress without cracking.
3Reliability
If ultra thin metal oxide layers are used, then electrical conductivity is improved, but light transmittance deteriorates
Solution Approach 1:
The patent employs a composite structure with multiple thin layers of AZO and gold. By distributing the functional requirements across multiple ultra-thin layers rather than using a single thick layer, the coating achieves both high electrical conductivity (through the gold and AZO layers) and high light transmittance (by keeping each individual layer thin to minimize optical interference).
4Object-affected harmful factors
If organic protective layers are applied to protect silver from environmental exposure, then corrosion resistance is improved, but service life deteriorates due to rapid degradation
Solution Approach 1:
The patent replaces the traditional approach of using organic protective layers over silver with a completely different material system (AZO-gold composite) that inherently provides both protection and functionality without requiring additional organic coating layers, eliminating the degradation issue associated with organic materials.
Solution Approach 2:
The inorganic AZO-gold composite structure provides inherent environmental stability and corrosion resistance without requiring additional organic protective layers. The composite materials work together to provide durable, long-lasting performance in harsh environmental conditions.
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 solution enhances durability and functionality by increasing light transmittance, flexibility, and corrosion resistance, while maintaining anti-reflective properties and radar attenuation, thus addressing the limitations of previous coatings.
Implementation Method 1
a first metal oxide layer including aluminum doped zinc (AZO)... a second metal oxide layer including AZO
Implementation Method 2
a metal layer including gold (Au)... wherein the metal layer is positioned over the first metal oxide layer
Implementation Method 3
electrically conductive multilayer stack having low sheet resistance to provide radar attenuation
Implementation Method 4
an aircraft canopy can drain or dissipate static electricity and thereby prevent or reduce the buildup of static charge on the canopy
Data Source
AI summary
A coated transparency including an electrically conductive multilayer stack is disclosed. The electrically conductive multilayer stack includes a first metal oxide layer including aluminum doped zinc (AZO), a metal layer including gold, and a second metal oxide layer including AZO. The electrically conductive multilayer stack has a low sheet resistance to provide radar attenuation and anti-static or static-dissipative properties, and has greater flexibility and resistance to corrosion than conventional multilayer stacks used to coat aircraft canopies and other substrates.