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Aufsatz
A framework for the computer-aided planning and optimisation of manufacturing processes for components with functional graded properties
(2015-02-17)
In this contribution a framework for the computer-aided planning and optimisation of functional graded components is presented. The framework is divided into three modules - the "Component Description", the "Expert System" for the synthetisation of several process chains and the "Modelling and Process Chain Optimisation". The Component Description module enhances a standard computer-aided design (CAD) model by a voxel-based representation of the graded properties. The Expert System synthesises process steps stored ...
Aufsatz
Effect of Cell Morphology on Flexural Behavior of Injection-Molded Microcellular Polycarbonate
(2022-05-19)
The quantitative study of the structure and properties relationship in cellular materials is mostly limited to cell diameter, cell density, skin layer thickness, and cell size distribution. In addition, the investigation of the morphology is generally carried out in two dimensions. Therefore, the
interrelation between morphological properties and mechanical characteristics of the foam structure has remained in an uncertain state. In this study, during the physical foaming process, a foam morphology is locally created ...
Aufsatz
Constant Temperature Approach for the Assessment of Injection Molding Parameter Influence on the Fatigue Behavior of Short Glass Fiber Reinforced Polyamide 6
(2021-05-13)
Short glass fiber reinforced plastics (SGFRP) offer superior mechanical properties compared to polymers, while still also enabling almost unlimited geometric variations of components at large-scale production. PA6-GF30 represents one of the most used SGFRP for series components, but the impact of injection molding process parameters on the fatigue properties is still insufficiently investigated. In this study, various injection molding parameter configurations were investigated on PA6-GF30. To take the significant ...
Aufsatz
Innovative Materials for Novel Concepts for Internal Heat Exchangers
(2018-07-27)
Internal heat exchangers are often employed in solar thermal applications as well as in many other applications that involve heat, and, for the most part, consist of metallic materials (copper, stainless steel). Corrugated stainless steel tubes are easy to assemble, and are commonly used in various storage geometries. In order to significantly reduce costs, alternative materials, such as plastics, can function as excellent substitutes. Alternative heat exchangers for the following examinations using various materials ...
Aufsatz
Thermal Properties of Plasticized Cellulose Acetate and Its β-Relaxation Phenomenon
(2021-04-21)
Cellulose acetate (CA), an organic ester, is a biobased polymer which exhibits good mechanical properties (e.g., high Young’s modulus and tensile strength). In recent decades, there has been significant work done to verify the thermal and thermomechanical behaviors of raw and plasticized cellulose acetate. In this study, the thermomechanical properties of plasticized cellulose acetate—especially its β-relaxation and activation energy—were investigated. The general thermal behavior was analyzed and compared with ...
Aufsatz
The Manufacture of Hot-Compacted Layered Composite Systems Made of Oriented Semifinished PP-Films
(2014-03-04)
Monoaxial stretched PP-films are used for the manufacture of hot-compacted layered composites. These are layered with stretched co-extruded coupling agent films, and are consolidated to laminates by means of a hot-compaction process, which employs pressure and temperature. This paper aims to examine the influence of the process settings on the properties of the composites during the hot-compaction process. For this purpose, the mechanical values will be determined by means of tensile testing variously compacted and ...
Aufsatz
Parameter recommendation for injection molding based on similarity analysis of injection molded parts
(2023)
Injection molding is a widespread manufacturing process for producing complex plastic shapes. The process is controlled by a large number of parameters, which show interactions with each other. Thereby the determination of an optimal operating point during sampling is a resource-consuming and demanding task. The data, which is generated during sampling, is usually not used for subsequent sampling processes. In the context of Industry 4.0, manufacturing companies attempt to optimize production efficiency to save time ...
Aufsatz
Baumwolle als Faserverstärkung
(2023)
Jedes Jahr landen große Mengen Textilen auf Deponien oder in der thermischen Verwertung. Ein Teil dieser Abfälle könnte allerdings auch als Rohstoffe für Verbundwerkstoffe dienen. Baumwollfasern eignen sich etwa als Verstärkungsfasern, die die mechanischen Eigenschaften von biobasierten Kunststoffen steigern. Durch die Nutzung solcher Abfallströme können in Zukunft kostengünstig und biobasiert Materialien verstärkt werden.
Aufsatz
Investigation of residual stresses in polypropylene using hot plate welding
(2020-08-05)
During the cooling process of the molten material, residual stresses appear because the reduced volume of the cooled material cannot fully fill the space formerly occupied by the molten material. The morphology in and around the weld is formed by different factors depending on the material and process parameters. Different morphological structures relate to different mechanical properties. The process parameters and the welding results including morphology and residual stress are linked together. In this article, ...
Aufsatz
Effects of blending poly(lactic acid) and thermoplastic polyester polyurethanes on the mechanical and adhesive properties in two-component injection molding
(2022-09-16)
One possible way to increase the use of bioplastics and thus contribute to a more resource-efficient and sustainable economy is to broaden the application range of such bioplastics. Poly(lactic acid) (PLA) is a promising and commercially available bio-based and biologically degradable polymer, which exhibits a high strength and stiffness but is very brittle. Blending with other polymers can lead to an enhancement of the ductility of the PLA. The goal of this work was to show that blending of PLA with a bio-based ...