Electrically assisted 3D printing of nacre-inspired structures with self-sensing capability

Area of Science:

• Materials Science and Engineering
• Bioinspired Materials
• Additive Manufacturing

Background:

• Natural nacre achieves high strength and toughness through its hierarchical brick-and-mortar structure.
• Lightweight yet strong materials are crucial for applications in sports, transportation, aerospace, and biomedicine.
• Replicating nacre's structure and properties in synthetic materials remains a significant challenge.

Purpose of the Study:

• To develop a method for creating nacre-inspired hierarchical structures with complex 3D shapes.
• To integrate mechanical reinforcement and electrical self-sensing capabilities into these bioinspired materials.
• To explore potential applications in advanced armor, aerospace, and biomedical devices.

Main Methods:

• Electrically assisted 3D printing was employed to fabricate nacre-inspired structures.
• Graphene nanoplatelets (GNs) were aligned using an electric field (433 V/cm) during the printing process.
• A polymer matrix served as the mortar, with aligned GNs acting as the bricks.

Main Results:

• The 3D-printed nacre with 2 weight % aligned GNs achieved a lightweight density of 1.06 g/cm³.
• The material exhibited specific toughness and strength comparable to natural nacre.
• The printed structures demonstrated electrical self-sensing capabilities, detecting damage through resistance changes.

Conclusions:

• A novel method for producing bioinspired hierarchical structures with complex 3D geometries was established.
• The developed material offers integrated mechanical reinforcement and electrical self-sensing functionalities.
• This technology presents promising avenues for advanced applications requiring lightweight, strong, and smart materials.