A Design Strategy for Removing the Debinding and Sintering Gas in Additive Manufactured Samples of a Bronze/Polylactic Acid Filament

by Tanya Fosdal | Feb 23, 2024 | research papers

“To lower the cost of additive manufacturing of metallic components, the goal of this work is to investigate and optimize a multi-step process by material extrusion (MEX) of a polylactide filament loaded with bronze to remove the gas produced during the debinding and sintering steps. First, by adjusting the infill (10%, 50%, and 100%), and then by designing and constructing internal passages to aid in the expulsion of gases that occur during the debinding, a calibration cube is created. Additionally, the impact of the cooling period during the debinding is examined. To assess how the technique changes shape, sizes, and internal structure, all the samples are ultimately weighed, scanned, and cut. In order to reduce deformation occurred during the debinding and sintering gases, a new design method has been developed. The method consists of the generation of internal channels which connect the voids of the infill and allow gases to flow out through a central channel. As seen, samples with ejection channels and an intermediate infill (i.e., 50%) both exhibit better attributes.”

Full paper published to Wiley Online Library 23 February 2024: https://onlinelibrary.wiley.com/doi/abs/10.1002/adem.202301722

Understanding Debinding and Sintering in Metal 3D Printing

Debinding and sintering are critical processes in metal 3D printing that significantly influence the final properties of the printed parts. Debinding involves the removal of binders used during the printing process, while sintering is the process of compacting and forming a solid mass of material by heat without melting it. Both steps are essential for achieving optimal mechanical properties and dimensional accuracy in the final product.

In the context of bronze/polylactic acid (PLA) filaments, effective debinding and sintering can prevent defects such as warping and internal voids. The research conducted by Tanya Fosdal highlights innovative strategies to enhance gas removal during these processes, ultimately leading to improved print quality and performance. Understanding these processes is vital for manufacturers looking to optimize their 3D printing workflows.

Innovative Techniques for Gas Expulsion

Gas expulsion during the debinding and sintering processes is a significant challenge in metal 3D printing, as trapped gases can lead to structural defects. The research paper discusses innovative techniques such as designing internal channels within the printed structure, which facilitate the escape of gases. This approach not only enhances the quality of the printed parts but also reduces the likelihood of deformation.

By adjusting the infill percentage and incorporating strategically placed ejection channels, the study demonstrates notable improvements in the mechanical properties of the final products. These techniques represent a significant advancement in additive manufacturing, providing practical solutions for manufacturers aiming to enhance the efficiency of their production processes.

Impact of Infill Structures on Print Quality

The choice of infill structure is crucial in determining the mechanical properties and overall quality of 3D printed components. In the research conducted, varying the infill percentages (10%, 50%, and 100%) allowed for a comprehensive analysis of how different structures affect gas expulsion and final part integrity. The findings indicate that an intermediate infill of 50% strikes a balance between strength and weight, leading to superior results.

These insights are particularly valuable for manufacturers looking to optimize their designs for specific applications. By tailoring infill structures to improve gas removal, companies can enhance the reliability and performance of their metal 3D printed parts, ultimately driving innovation in the industry.

Accessing the Full Research Paper

For those interested in a more in-depth understanding of the methodologies and findings presented in the study by Tanya Fosdal, the full research paper is available through the Wiley Online Library. This resource provides comprehensive details on the experimental setups, results, and implications of the findings for the field of metal 3D printing.

Accessing the full paper not only allows for a deeper exploration of the techniques discussed but also serves as a valuable reference for researchers and practitioners aiming to implement these strategies in their own additive manufacturing processes. The link to the full paper can be found here: Wiley Online Library.