On the Pin-Bearing Strength of Additively Manufactured Polymer Parts

Area of Science:

• Materials Science
• Mechanical Engineering
• Additive Manufacturing

Background:

• Additive manufacturing (AM) is increasingly used for final products, necessitating robust mechanical properties.
• Evaluating the structural integrity of AM parts is crucial for reliable applications.
• The pin-bearing test assesses the stress response of fasteners, plates, and holes in components.

Purpose of the Study:

• To determine the pin-bearing strength and stiffness of polymer samples fabricated via fused deposition modeling (FDM).
• To investigate the influence of the specimen width to hole diameter ratio on the mechanical performance and failure modes of AM parts.
• To gain insights into the damage mechanisms and failure behavior through microscopic analysis.

Main Methods:

• Fabrication of polymer specimens using fused deposition modeling (FDM) with two distinct materials.
• Preparation of specimens with varying hole diameters to study the width-to-hole ratio effect.
• Conducting tensile tests, scanning electron microscopy (SEM) on damaged areas, and digital image correlation (DIC) for strain field analysis.

Main Results:

• Quantification of stiffness and pin-bearing strength for the additively manufactured specimens.
• Observation of the preferred bearing failure mode in several tested samples.
• Detailed insights into damage mechanisms and failure behavior derived from SEM and DIC analyses.

Conclusions:

• The study provides critical data on the pin-bearing strength of FDM-printed polymer parts.
• Findings highlight the significant impact of the hole diameter ratio on structural integrity.
• The research contributes to the development of stronger and more reliable designs for additive manufactured components.