Polycarbosilane Barrier Coating for High-Temperature Protection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional barrier coatings for silicon-based ceramic materials are expensive, time-consuming to apply, and unable to withstand temperatures above 1482°C, leading to decomposition when exposed to high-temperature water, despite being used in aerospace and other industries where high heat resistance is required.
Innovation Solution
A barrier coating resin formulation comprising a reaction product of polycarbosilane preceramic polymer and organically modified silicon dioxide preceramic polymer, combined with a filler, which provides increased resistance to heat, moisture, and oxidation, and can be applied using a low-cost, low-complexity spray coating process under ambient conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If conventional barrier coatings (silicates, YSZ) are used, then protection against heat and oxidation is provided, but the cost increases and the temperature resistance is limited to below 1482°C
Solution Approach 1:
The patent changes the chemical composition parameters of the barrier coating by using polycarbosilane preceramic polymers with specific molecular structures and ratios (e.g., vinyl groups, hydride groups) to achieve both high temperature resistance (above 1482°C) and cost-effectiveness. The formulation includes specific ratios of preceramic polymer to filler (e.g., 1:4 to 1:10 by weight) to optimize performance.
Solution Approach 2:
The patent creates a composite barrier coating system combining polycarbosilane preceramic polymer with filler materials (such as alumina, silica, or other ceramic powders) to achieve enhanced temperature resistance and chemical stability. This composite approach allows the coating to withstand temperatures above 1482°C while maintaining cost-effectiveness.
2Reliability
If multi-layer barrier coatings are applied using plasma spray processes, then comprehensive protection is achieved, but the manufacturing time and equipment complexity increase
Solution Approach 1:
The patent merges multiple coating functions (adhesion, oxygen barrier, temperature resistance) into a single-layer barrier coating formulation. The polycarbosilane preceramic polymer provides adhesion to the substrate while simultaneously forming a protective barrier against oxidation and heat, eliminating the need for separate multi-layer applications and reducing manufacturing time.
Solution Approach 2:
The patent replaces the complex plasma spray mechanical system with a simpler spray coating process that applies the preceramic polymer formulation. The coating is applied in a liquid or paste form and then cured, substituting the high-energy plasma spray mechanism with a more straightforward coating and curing process that reduces equipment complexity and manufacturing time.
3Reliability
If conventional plasma spray processes are used, then barrier coating is formed, but specialized equipment and vacuum environment are required
Solution Approach 1:
The patent replaces the specialized plasma spray equipment and vacuum environment with a conventional spray coating system that operates in ambient conditions. The preceramic polymer formulation is applied using standard spray equipment, and the coating is cured through thermal treatment, eliminating the need for complex plasma generation equipment and vacuum chambers.
Solution Approach 2:
The patent uses an inert or controlled atmosphere during the curing process of the barrier coating to prevent oxidation of the preceramic polymer before it fully cures. This allows the coating to be applied in ambient conditions while maintaining coating quality through controlled curing in a low-oxygen environment, eliminating the need for vacuum conditions during application.
4Object-affected harmful factors
If barrier coatings are applied to protect against high-temperature water, then oxidation resistance is improved, but decomposition occurs above 1482°C
Solution Approach 1:
The patent changes the chemical composition and molecular structure of the barrier coating by using polycarbosilane preceramic polymers with specific functional groups (vinyl, hydride) that form stable ceramic networks at high temperatures. This chemical parameter change enables the coating to withstand temperatures above 1482°C while maintaining oxidation resistance and preventing decomposition.
Solution Approach 2:
The patent creates a composite coating system where the polycarbosilane preceramic polymer forms a stable ceramic matrix when cured, combined with filler materials that enhance high-temperature stability. This composite structure provides both oxidation resistance and the ability to withstand temperatures above 1482°C without decomposition, even when exposed to high-temperature water.
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 offers high-temperature capability with low mass loss and reduced costs, as it can be formed without specialized equipment, providing effective protection up to 5000°F (2760°C) and reducing the risk of decomposition from high-temperature water exposure.
Implementation Method 1
a barrier coating is disclosed and comprises a reaction product of at least one polycarbosilane preceramic precursor and at least one organically modified silicon dioxide preceramic polymer
Implementation Method 2
The barrier coating resin formulation is applied to a substrate and cured to form a cured barrier coating over the substrate
Implementation Method 3
The solution offers high-temperature capability with low mass loss and reduced costs, as it can be formed without specialized equipment, providing effective protection up to 5000°F (2760°C)
Implementation Method 4
The EBC prevents the reaction of water and other reactive species with the silicon, which can form reaction products (e.g., silicon hydroxide) that volatilize and cause erosion of the silicon-based ceramic material
Data Source
AI summary
A barrier coating resin formulation comprising at least one polycarbosilane preceramic polymer, at least one organically modified silicon dioxide preceramic polymer, at least one filler, and at least one solvent. A barrier coating comprising a reaction product of the at least one polycarbosilane preceramic polymer and the at least one organically modified silicon dioxide preceramic polymer and the at least one filler is also disclosed, as are articles comprising the barrier coating, rocket motors comprising the barrier coating, and methods of forming the articles.