Interface Healing Between Adjacent Tracks in Fused Filament Fabrication Using In-Process Laser Heating

Area of Science:

• Materials Science
• Additive Manufacturing
• Polymer Science

Background:

• Fused filament fabrication (FFF) is a popular additive manufacturing technique for creating complex thermoplastic parts.
• A key limitation of FFF is the anisotropic mechanical properties of printed parts due to track-based deposition.
• Poor interface adhesion between adjacent deposited tracks leads to anisotropic behavior and reduced mechanical strength.

Purpose of the Study:

• To introduce and evaluate an in-process laser heating method for improving interface adhesion in FFF parts.
• To enhance the bonding strength between adjacent deposited tracks.
• To mitigate the anisotropic mechanical properties of FFF-fabricated components.

Main Methods:

• An in-process laser heating technique was applied during the FFF process.
• Laser heating increased the interface temperature between adjacent deposited tracks.
• Polymer reptation and bonding at the interface were promoted by the elevated temperature.

Main Results:

• Laser heating significantly improved the flexural strength between adjacent tracks within the same layer.
• The enhanced flexural strength exceeded that of control samples tested along the track direction.
• Load-displacement curves and fractured surface morphology analysis confirmed the effectiveness of laser-induced interface healing.

Conclusions:

• In-process laser heating is an effective method for healing interface adhesion in FFF.
• This technique successfully enhances the bonding strength and mechanical properties of 3D printed parts.
• The study demonstrates a viable approach to overcome FFF's inherent anisotropy.