Selective laser sintering of polymer nanocomposites

• Main Author: Wahab, Md Saidin
• Format: Thesis
• Language: English
• Published: 2008
• Subjects: TA Engineering (General). Civil engineering (General); TA401-492 Materials of engineering and construction. Mechanics of materials
• Online Access: http://eprints.uthm.edu.my/7192/1/24p%20MD%20SAIDIN%20WAHAB.pdf; http://eprints.uthm.edu.my/7192/
• Institution: Universiti Tun Hussein Onn Malaysia

his thesis presents research to investigate the use of polymer nanocomposites (PNCs) as a raw material for the selective laser sintering (SLS) process. The novelty of this work lies in the fact that PNC materials have been prepared for the SLS rocess through mechanical blending (ball milling) and solution blending techniques. PNC materials containing a polyamide (PA) and nano particles (5wt%) were roduced by mechanical blending and solution blending with the aim to improve the echanical properties. In mechanical blending, commercial Durafom PA was tumble nd ball milled with several nano particle materials: yttrium stabilised zirconia (YSZ), enton 166 (Bl66), Bentolite WH (BWH) and Mineral colloide MO (MCMO). For olution blending, commercial polyamide 6 (PA6) was dissolved in formic acid (HC02H) together with the same nano additive materials used in the mechanical lending and spray-dried to create powder. Material characteristics (physical and hemical elements), thermal properties, powder bed density and flowability of the aterials have all been investigated. The materials were processed on a C02 SLS xperimental machine where the SLS processing characteristics and processing arameters were established. Mechanical properties of the PNCs were evaluated and he results were compared with the unfilled base polymer. From the result of the mechanical blending process, only blended uraform/YSZ was successfully processed by SLS, and results were also limited for he blended Duraform/YSZ as a result of improper dispersion of nano particles in the atrix. Good dispersion of additives was achieved by solution blending, however the A6 was degraded during the material preparation and spray drying process which esulted in the formation of porous structure and low strength. However the addition of 5 wt% nano particles in the PA6 was shown to increase strength by an average of 0-60%. Further work on powder preparation is required in order to fully realise hese performance benefits.