Establishment of a rotary print head to effect residual stresses and interlayer bonding in an FLM-process
Loading...
Date
2021-07-27
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
n fused layer modeling (FLM) manufacturing technology, there is an increased demand for semi-crystalline materials due to their favorable mechanical properties, such as high strength and toughness. The reasons for their limited use are process-related residual stresses and reduced interlayer bonding, resulting in component distortion, warping and poor strength. Addressing these problems, this paper presents the development and implementation of a rotary print head that enables local laser pre-deposition heating and forced air cooling in the 2.5-dimensional FLM process. Samples of polypropylene are fabricated to investigate the effects of the modified process on residual stresses and interlayer bonding. The investigations show that local laser pre-deposition heating can positively influence the interlayer bonding. In combination with a reduction of the extrusion temperature and additional cooling, it is possible to considerably reduce the residual stresses. The results of this research show that pre-deposition heating and forced air cooling significantly improve the processability of semi-crystalline thermoplastics in the FLM process.
Description
Table of contents
Keywords
FLM, FDM, Pre-deposition heating, Laser, Rotary print head, Polypropylene, Additive manufacturing, Residual stress, Warping, Interlayer bonding