Composite Panel Crack Resistance via Resin Parameter Changes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Recreational vehicle sidewall panels made from glass fiber-reinforced composite materials are prone to micro-cracking due to thermal fatigue, leading to cracking and increased material costs and weight when thickness is increased to mitigate this issue.
Innovation Solution
A composite sheet manufacturing method involving a crack-resistant reinforcement layer with a filler, such as calcium carbonate or mica, and self-healing micro-capsules, along with a non-conventional resin like vinyl ester or epoxy, and a barrier layer to prevent crack propagation, is applied between the gel coat and the reinforcement panel.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the layer thickness of the fiber reinforced laminate is increased to reduce cracking, then the crack resistance is improved, but the panel weight and cost increase significantly
Solution Approach 1:
The patent changes the chemical composition parameters of the resin by incorporating vinyl ester resin (20-80 parts by weight) and epoxy resin (5-50 parts by weight) in addition to conventional polyester resin. This parameter change creates a more flexible and crack-resistant composite material that prevents cracking without requiring increased layer thickness, thereby avoiding the weight penalty associated with thicker panels.
Solution Approach 2:
The patent uses a composite resin system combining multiple resin types (polyester, vinyl ester, and epoxy) with glass fiber reinforcement. This multi-component composite material leverages the complementary properties of each resin to achieve superior crack resistance and flexibility while maintaining optimal weight characteristics, resolving the contradiction between crack resistance and weight.
2Reliability
If the layer thickness of the fiber reinforced laminate is increased to reduce cracking, then the crack resistance is improved, but the manufacturing cost increases
Solution Approach 1:
The patent modifies the resin composition parameters by incorporating vinyl ester resin (20-80 parts by weight) and epoxy resin (5-50 parts by weight) alongside polyester resin. This parameter change enhances crack resistance through improved material flexibility and adhesion, eliminating the need for thicker layers and reducing material costs while maintaining manufacturing efficiency.
Solution Approach 2:
The patent employs a composite resin system that combines polyester resin with vinyl ester and epoxy resins to create a material with superior crack resistance. This composite approach provides effective crack prevention through enhanced material properties rather than increased thickness, thereby controlling manufacturing costs.
3Ease of manufacture
If conventional polyester resin is used with chopped glass and resin composite reinforcement, then the manufacturing process is simple, but the panels are prone to micro-cracking due to thermal fatigue
Solution Approach 1:
The patent enhances the conventional polyester resin system by incorporating vinyl ester resin (20-80 parts by weight) and epoxy resin (5-50 parts by weight) to create a composite resin system. This composite material maintains the simplicity of the existing manufacturing process while significantly improving crack resistance through the synergistic properties of multiple resins that provide better flexibility and thermal fatigue resistance.
Solution Approach 2:
The patent changes the resin composition parameters by adding vinyl ester and epoxy resins to the conventional polyester resin formulation. This parameter change improves the material's resistance to thermal fatigue and micro-cracking while preserving the ease of manufacture, as the enhanced resin system can be applied using the same vacuum bagging and curing 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 method significantly reduces the susceptibility to cracking by more than 50% and maintains panel strength without increasing weight or cost, allowing for improved durability and reduced energy consumption.
Implementation Method 1
Recreational vehicle sidewall panels are exposed to various weather conditions, including heat, cold and humidity. The sidewall panels have a tendency to crack due to weather changes. The phenomenon is called micro-cracking, or thermal fatigue cracking, or sometimes thermal shock cracking.
Implementation Method 2
A composite sheet manufacturing method involving a crack-resistant reinforcement layer with a filler, such as calcium carbonate or mica, and self-healing micro-capsules
Implementation Method 3
a barrier layer to prevent crack propagation
Implementation Method 4
at least one coat of a resin material, containing a curable resin and optionally a filler, and a fibrous reinforcement material are applied over the outer coat (over the barrier layer if present) to form a composite reinforcement layer
Data Source
AI summary
A durable composite sheet is provided, with a method of manufacturing the composite sheet. The method includes using a crack-resistant reinforcement panel between a gel coat and a reinforcement panel, which may be of lauan or of other materials. At least one outer coat of material is applied onto a mold surface. A barrier layer may be formed on the outer coat, preferably by spraying. At least one coat of a resin material, containing a curable resin and optionally a filler, and a fibrous reinforcement material are applied over the outer coat (over the barrier layer if present) to form a reinforcement layer. The reinforcement panel is applied to the crack-resistant reinforcement layer, and is bonded thereto.