Abstract
In the present study, recyclability of Laser PP CP 75 polypropylene powder from Diamond Plastics GmbH was determined by characterizing and comparing the used powder after each cycle with material from previous cycles and with fresh powder. The melt flow index of Laser PP CP 75 was affected by recycling since it was observed to change by 30.62% after the 8th 100% re-use cycle, a lower value than PA 12 of 66.04%, for the 6th re-use cycle. Parts printed with virgin Laser PP CP 75 had an average dimensional error of 3.02% (virgin material) and 4.06% after the 4th 100% re-use cycle, which raises concerns about the commercial viability of the material. After the 4th re-use cycle, the printed parts had distorted edges and failed to print after the 9th print cycle. Lastly, tensile testing revealed a skewed bell-shaped curve of strength versus the number of recycles with the highest ultimate tensile strength occurring for the second 100% re-use cycle (7.4 MPa). The curves for elastic modulus and percentage elongation were inverted with minimum points for the 2nd 100% re-use cycle. Overall, the experimental work confirmed that the properties of polypropylene powder were affected by recycling in polymer laser sintering, but the powder exhibited superior characteristics upon recycling to those of the predominantly used PA 12 powder.
Highlights
Laser Powder bed fusion (L-PBF) is one of the most common additive manufacturing (AM) techniques for polymers
The present study investigates the recyclability of a new polypropylene material (Laser PP CP 75) from Diamond Plastics to determine if it is 100% re-usable
Uniaxial tensile testing and dimensional analysis tests were employed to examined for the presence of “orange peel,” which is common with PA 12
Summary
Laser Powder bed fusion (L-PBF) is one of the most common additive manufacturing (AM) techniques for polymers. The process uses a heat source to fuse powder materials to create three-dimensional objects from model data by building components layer-upon-layer [1]. AM technologies because it does not require support structures, since the unsintered powder supports the printed parts [1]. This advantage allows for printing complex parts with high geometrical and dimensional accuracy and excellent mechanical properties, since post-processing is not needed. Many parts can be stacked in the powder bed, increasing productivity [1]. Polymer materials are subjected to high temperatures for long hours during laser sintering, which degrades them, hindering subsequent recycling
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
