Carbon Nanotube Structural Core With Balanced In-Plane Modulus
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for core structures and composite panels with improved mechanical properties such as stiffness, strength, and toughness, particularly for applications in aircraft, trains, and boats, where existing high modulus high strength fiber nonwoven sheets do not adequately meet the required performance standards.
Innovation Solution
A structural core comprising a nonwoven fibrous reinforcement web of carbon nanotubes coated with a thermoset or thermoplastic resin, where the carbon nanotubes are oriented to maintain a modulus ratio of no greater than 2.0 in different directions, and the resin content ranges from 15 to 75 weight percent, enhancing the mechanical properties of the core structure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If high modulus high strength fiber nonwoven sheets are used for core structures, then strength and stiffness are improved, but the mechanical properties do not adequately meet the required performance standards for aircraft, trains, and boats
Solution Approach 1:
The patent applies composite materials by combining carbon nanotubes with thermoset or thermoplastic resin to create a reinforced core structure. The carbon nanotubes provide exceptional strength and stiffness, while the resin matrix binds them together and transfers loads effectively. This composite approach enables the core structure to meet or exceed the required performance standards for aircraft, trains, and boats that conventional fiber nonwoven sheets cannot achieve alone.
Solution Approach 2:
The patent changes the material parameters by using carbon nanotubes with specific orientation (modulus ratio no greater than 2.0) and controlled resin content (15-75 weight percent). These parameter optimizations ensure that the composite achieves balanced mechanical properties in multiple directions while meeting the stringent performance requirements for transportation applications.
2Strength
If carbon nanotubes are oriented to achieve high in-plane Young's modulus of at least 14 GPa, then stiffness is improved, but the modulus ratio between orthogonal directions must be maintained at no greater than 2.0
Solution Approach 1:
The patent applies local quality by creating specific orientation zones within the carbon nanotube reinforcement web. The carbon nanotubes are oriented such that the ratio of modulus in the plane of the web in a first direction to the modulus in a second direction orthogonal to the first direction is no greater than 2.0, while maintaining an in-plane Young's modulus of at least 14 GPa. This controlled orientation distribution achieves both high stiffness and balanced mechanical properties in orthogonal directions.
3Strength
If resin content is increased to enhance mechanical properties, then strength and toughness are improved, but the weight and density of the core structure increase
Solution Approach 1:
The patent optimizes the resin content parameter within the range of 15-75 weight percent of the total composite. This controlled resin content provides sufficient matrix material to bind the carbon nanotubes and transfer loads, enhancing strength and toughness, while avoiding excessive resin that would unnecessarily increase weight and density of the core structure.
Data Source
Figure 1A~1B
Figure 2~3
Figure 4
AI summary
This invention pertains to a structural core comprising a nonwoven fibrous reinforcement web of carbon nanotubes, the web being coated with a thermoset or thermoplastic resin wherein the carbon nanotubes are oriented within the reinforcement web such that, after resin coating, the ratio of modulus in the plane of the web in a first direction to the modulus in a second direction orthogonal to the first direction is no greater than 2.0; the in-plane Young's modulus of the resin coated web is at least 14 GPa and the coating resin comprises from 15 to 75 weight percent of the weight of web plus resin.