Electro-active Variable-Stiffness Corrugated Structure Based on Shape-Memory Polymer Composite

Area of Science:

• Materials Science
• Polymer Science
• Aerospace Engineering

Background:

• Shape-memory polymers (SMPs) offer tunable stiffness and shape recovery capabilities.
• Morphing skins require materials with adaptable mechanical properties for diverse environments.
• Existing materials may lack the necessary anisotropy and rapid response for advanced applications.

Purpose of the Study:

• To develop a variable-stiffness corrugated sheet using a carbon fiber felt (CFF)-reinforced SMP composite.
• To achieve extreme mechanical anisotropy for morphing skin applications.
• To investigate the material's response to electrical Joule heating for stiffness control and shape memory actuation.

Main Methods:

• Fabrication of a corrugated sheet from a CFF-reinforced epoxy-based SMP composite.
• Characterization of mechanical properties, including in-plane and out-of-plane stiffness.
• Evaluation of electrical heating performance and shape-memory effect via experiments.

Main Results:

• The corrugated sheet demonstrated extreme mechanical anisotropy, with low in-plane and high out-of-plane stiffness.
• Variable stiffness was achieved through temperature changes induced by efficient Joule heating.
• The material exhibited considerable deformation ability and a reliable shape-memory effect.

Conclusions:

• The CFF-reinforced SMP composite corrugated sheet is a promising candidate for morphing skins.
• Its tunable stiffness and mechanical anisotropy, activated by electrical heating, meet key application requirements.
• The material offers integrated actuation and variable stiffness without external heating components.