Search
Now showing items 181-190 of 192
Aufsatz
Modification of self-reinforced composites (SRCs) via film stacking process
(2022-02-25)
This work presents the mechanical behavior of self-reinforced composites (SRCs) manufactured and modified via film stacking. For modification, interleaved films made of polypropylene (PP), a thermoplastic elastomer and a polyolefin engage were combined in different ways to induce the elastic modifier into the matrix material. The content of modifier was also varied in two ways. First, the films were produced out of a single material and second out of a compound. So, the same content of modifier was implemented in two ...
Aufsatz
Bend Straightening of a Carbonitrided Gear Shaft – Consequences on Residual Stresses and Retained Austenite near the Surface
(2017-06-20)
Carbonitriding of shafts in drive technology is strongly connected with distortion. Bend straightening is an important process step in order to eliminate distortion without removing the hardened surface layer. As shown in several investigations, even for simple part geometries, bending induced stresses and plastic deformations have a strong impact not only on the residual stress state but also on the microstructure after straightening. As gear shafts become increasingly filigree and complex in their geometry, the ...
Aufsatz
Investigation of the adhesive strength in a combined compaction and back-injection process to produce back-injected self-reinforced composites (SRCs)
(2022-03-08)
This publication investigates the adhesion between an injection molded component and a self-reinforced composite (SRC) produced in a combined compaction and back-injection process to produce back-injected self-reinforced composites. To study the influence of the process, the parameters barrel temperature, time of injection, and tool temperature were varied. In addition, samples were taken at different positions along the flow path. In light of the orthotropic material behavior of SRCs, investigations were conducted ...
Aufsatz
Climatic Ageing of Components of Polymer Based Electrochromic Devices
(2013-09-09)
Combining a shading function and a polycarbonate window displays an attractive alternative to the currently employed glass roof in vehicles. However, the ageing of such a device must be investigated before any application. Therefore, our investigations focus on the ageing of the components of a polycarbonate based electrochromic device. The optical, electrical, mechanical and electrochemical properties of the ion storage layer as well as the substrate will be assessed after storage in a climate with a high humidity ...
Aufsatz
UV Surface Treatment of Polycarbonate for Adhesion Improvement to Liquid Silicone Rubber (LSR)
(2018)
The adhesion of self-adhesive liquid silicone rubbers to thermoplasts is only possible for a few selected material combinations without a surface pretreatment. A UV pretreatment is effective for polycarbonate and short irradiation periods are sufficient. To clarify the required irradiation conditions that result in an improvement of adhesion, the varying irradiation conditions were assessed. FTIR-ATR spectroscopy was used for surface analysis to characterize the change in the polymer surface.
Aufsatz
Textile Waste Becomes Plastic Composites
(2023-09)
Every year, large quantities of textiles end up in landfills or in thermal recycling. However, some of this waste could also serve as raw materials for composite materials. Left-over cotton fibers of the textile industry, for example, are suitable as reinforcing fibers that enhance the mechanical properties of bio-based plastics. By using such waste streams, materials can be reinforced in a cost-effective and bio-based way in the future.
Aufsatz
Holzdesign trifft Kunststofftechnik
(2022)
Werkstoffverbunde aus Holzgeweben in einer thermoplastischen Matrix verbinden die Idee des textilen Holzbaus mit der Faserverbundtechnologie. In einem Projekt werden Fassadenelemente aus solchen Wood Textile Composites hergestellt. Dabei spielt neben den mechanischen Anforderungen auch die gestalterische Seite und die Akzeptanz der zukünftigen Nutzer eine wichtige Rolle.
Aufsatz
Characterization of wood-based multi-material systems under dynamic impact stress
(2018)
Due to its naturally grown properties, wood has played a rather subordinate role as a material for technical applications up to now. In this paper, multi-material systems based on veneers of beech (Fagus sylvatica) with different reinforcing variants were investigated. In addition to the influence of different adhesive systems (urea formaldehyde and polyurethane), the effect of reinforcing by aramid fiber fabric and stainless steel foil in different climates was examined. At the center of the investigations were ...
Aufsatz
Wood-Polypropylene Composites: Influence of Processing on the Particle Shape and Size in Correlation with the Mechanical Properties Using Dynamic Image Analysis
(2018-11-16)
The particle size and shape are of momentous significance for the mechanical properties of plastic composites. However, natural fillers, like wood, are not consistent in these attributes. In order to investigate the shared traits between these characteristics, WPCs were produced using polypropylene, hardwood and softwood fillers with different particle sizes and a coupling agent. Afterwards, specimens were processed using an injection molding machine. The filler sizes and shapes were measured using dynamic image ...
Aufsatz
Investigations on Tightness of Polymer-Metal Hybrids in Environments with Thermal, Media, and Mechanical Loads
(2017-07-31)
With polymer-metal hybrids becoming more commonly used as structural components it was investigated how they perform in complex environments with combined thermal, media, and mechanical loads. Special attention was put on media tightness under said loads. This paper sums up the activities of the polymer technology research group of the University of Kassel on hybrids produced by overmolding metal inserts. Investigations concerning joint strength and influence of (cyclic) temperature loads and chemical corrosion on ...