Characterisation of the thermal ageing effects on the mechanical properties when reusing polyamide 12 in the selective laser sintering process

• Main Authors: Deckert, M. (Author), du Maire, P. (Author), Johlitz, M. (Author), Öchsner, A. (Author), Sert, E. (Author)
• Format: Article
• Language: English
• Published: John Wiley and Sons Inc 2022
• Subjects: Building process; Key technologies; Laser heating; Manufacturing IS; mechanical properties; Polyamid; polyamide 12; Poly-amide 12; powder recycling; Powder recycling; Process chambers; Production cost; Reuse; Scanning electron microscopy; selective laser sintering; Sintering; Tensile strength; Tensile testing; Thermal ageing; Thermal aging; Thermal aging effects
• Online Access: View Fulltext in Publisher
• Physical Description: 6
• ISBN: 09335137 (ISSN)
• DOI: 10.1002/mawe.202100393

Additive manufacturing is one of the key technologies for the future production of complex and individualised components. One of the most challenging questions to minimize the production cost is the reuse of the powder leftover after the building process. This study investigates the influence on the mechanical properties when reusing the leftover powder out of the process chamber up to four times. Tensile test specimens are produced and investigated. The results show a decreasing in the ultimate tensile strength with repeated reuse of the leftover powder. After four times of reuse the strength increases again. This cannot be explained by the literature and has to be verified in further investigations. The investigations reveal a high mechanical anisotropy as the strength highly depends on the component orientation in the process chamber. The particle shape does not show any differences between virgin and aged powder under the scanning electron microscope. © 2022 The Authors. Materialwissenschaft und Werkstofftechnik published by Wiley-VCH GmbH.