January 1, 2019 by admin 0 Comments

Additive Manufacturing of Polyaryletherketones

Authors
Manuel Garcia-Leiner Ph.D. *, Oana Ghita †, Robert McKay M.B.A., M.S.F. ‡, Steven M. Kurtz Ph.D. §
Abstract
Additive manufacturing (AM), otherwise known as three-dimensional printing (3DP), is a growing technology area comprising a spectrum of processes that allow production of solid objects of virtually any shape from information obtained from a digital object. These days, AM processes drive major innovations in engineering, manufacturing, art, education, and medicine. However, most AM processes are not necessarily new. Introduced commercially in the 1990s mainly through prototyping efforts for the manufacture of complex metal parts, AM processes have almost a 30-year history for plastics, and have driven the development of multiple commercial products through manufacturing techniques ranging from stereo-lithography to laser-based powder fusion processes. A growing number of polymeric resins intended for AM have become available in recent times due to developments of new processes and technological advancements. Of these, high-performance thermoplastics such as the polyaryletherketones (PAEKs) are perhaps the most promising candidates for demanding engineering applications. Polymers such as polyetheretherketone (PEEK), polyetherketoneketone (PEKK), and polyetherketoneetherketoneketone (PEKEKK), could revolutionize and enable the use of additively manufactured plastic parts in critical environments. However, despite their similarity in terms of chemistry and composition, commercially available PAEK resins show varying physical properties due to their molecular size-dependent structural differences that make them function differently in common AM processes. This chapter describes some of the advancements and opportunities for PAEK polymers in AM processes, as well as the relationships between structure and property and the morphological changes observed in these materials when subjected to conditions typically found in common AM processes.

July 31, 2016 by admin 0 Comments

Adaptive modeling method for 3-D printing with various polymer materials

Authors
Gobong Choi & Sungmin Kim
Abstract
An adaptive modeling method has been developed to improve the accuracy of an FDM type 3-D printer especially when printing complex small objects. The thermal and flow properties of PLA, ABS, and HIPS were measured using various types of rheological analysis. The relationship between those results and dimensional errors were analyzed. From this relationship, calibration factors were calculated for correcting the error between virtual and actual models. Image processing software has been developed to measure the dimension of printed samples. A model generation software has been developed to generate calibrated models using adaptive modeling method. The efficiency of system was verified through statistical analysis on the difference between the models with and without calibration.

August 31, 2015 by admin 0 Comments

Morphology and Properties of Textiles Manufactured by Three-Dimensional Printing Based on Fused Deposition Modeling

Authors
Lee Sun Hee
Abstract
In this study, the possibility of textile manufacture by 3D printing based on fused deposition modeling (FDM) was investigated. Among the various filaments that can be used for 3D printing, three polylactic acid (PLA) filaments and one thermoplastic polyurethane (TPU) filament was collected and then examined by dynamic mechanical thermal analysis (DMTA), differential scanning calorimetry (DSC), and a tensile test. An Stereolithograpy (STL) file with a 3D textile model was prepared and transformed into a G-code file using a G-code generator. The extrusion conditions for 3D printing were controlled by nozzle speed, nozzle temperature, thickness of the outer layer, height of the layer, and extrusion speed. Textiles manufactured by 3D printing based on FDM using PLA and TPU filaments were obtained. A 3D textile sample prepared using TPU filament was analyzed for morphology, and thermal and tensile properties, and the following results were obtained: melt temperature of approximately 204∘C, breaking load of 14 N, and elongation of 36%. Consequently, the applicability of 3D printing based on FDM for manufacturing textiles using TPU filament was confirmed.