Investigation of Fiber-Matrix Interface Strength via Single-Fiber Pull-Out Test in 3D-Printed Thermoset Composites: A...

Area of Science:

• Materials Science
• Mechanical Engineering
• Additive Manufacturing

Background:

• Additive manufacturing (AM) of fiber-reinforced thermoset composites is growing, especially in aerospace.
• Existing methods for measuring fiber-matrix interface strength in AM composites are complex and expensive.
• Precise interface strength data is vital for optimizing composite performance.

Purpose of the Study:

• To develop a novel, cost-effective methodology for single-fiber pull-out tests.
• To quantify the interface shear strength in additively manufactured thermoset composites.
• To validate the new method using carbon fiber and epoxy matrix composites.

Main Methods:

• Developed a technique for embedding single fibers within composite test specimens.
• Utilized a conventional mechanical testing system for fiber pull-out experiments.
• Characterized the interfacial shear strength through precise pull-out force measurements.

Main Results:

• Successfully embedded carbon fibers within the thermoset epoxy matrix.
• Achieved precise characterization of fiber pull-out strength.
• Determined an average interfacial strength of 2.4 MPa between carbon fiber and the epoxy matrix.

Conclusions:

• The novel single-fiber pull-out test is a viable and affordable method for assessing interface strength.
• This methodology can be applied to various additively manufactured composite materials.
• The findings contribute to advancing composite material fabrication for enhanced mechanical properties.