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Aufsatz
Process Influences in the Combined Compacting and Back-Injection Process to Produce Back-Injected Self-Reinforced Composites (SRCs) – Analysis via Multiple Regression Modelling
(2021-11-21)
A new process to produce back-injected self-reinforced composites (SRCs) is presented. In contrast to other investigations on back-injection of SRCs, a process is presented which allows compacting and back injection of SRCs in one step where the SRCs are partly consolidated only via melt pressure inside the cavity. The mechanical properties of SRCs depend to a large extent on the process parameters of temperature and pressure during manufacture. These parameters are not yet known for back-injected areas. Sensors ...
Aufsatz
Mechanical Characterization and Simulation of Wood Textile Composites (WTC) supported by Digital Image Correlation (DIC)
(2023-05-30)
Wood Textile Composites (WTC) based on willow wood fabrics and polypropylene were produced using a hot compacting process in order to open up new and innovative areas of applications for wood. Due to their attractive and variable design, the WTCs are to be used in areas with a high visual impact, for example as a facade element. In tensile and 3-point bending tests, it was shown that the mechanical properties of WTC are strongly dependent on the heterogeneous structure of the composite. Both strength and elongation ...
Dissertation
Optimierung des Risikomanagements als Beitrag zur Steigerung des Projekterfolgs bei Produktentwicklungsprojekten am Beispiel der Automobilindustrie
(2024)
Die zunehmende Projektifizierung der letzten Jahrzehnte hat dazu geführt, dass der Beitrag von Projekten zur Erreichung der Unternehmensziele und damit zur unternehmerischen Wert-schöpfung in gleichem Maße gestiegen ist. Gleichzeitig sind Projekte aufgrund ihres einzigar-tigen Charakters mit Risiken und Unsicherheiten behaftet, deren Auftreten im Kontext der Produktentwicklung in der Automobilindustrie durch den Produktivitätsdruck sowie die stetig steigende Komplexität und Dynamik noch verstärkt wird. Die negativen ...
Aufsatz
High Consistency Silicone Rubber Foams
(2024-04-23)
Silicone elastomers are high-performance plastics. In the extrusion process, only high-consistency silicone rubbers were used. In order to reduce the cost and weight, silicone rubbers can be foamed during processing. In this study, high-consistency silicone rubber is processed with different physical and chemical blowing agents. The resulting reaction kinetics, as well as the mechanical and morphological properties, had been investigated and compared with each other. This showed that the chemical blowing agent ...
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
Influences on the mechanical properties of SRCs in a combined compacting and back injecting process
(2022-03-03)
In this research paper, the effects of the combined compacting and back-injection process to produce back-injected self-reinforced composites on the mechanical properties of the self-reinforced composites (SRCs) are investigated. For this purpose, the parameters barrel temperature, time of injection and holding pressure were varied for the back injection. Tensile and bending tests were carried out on the SRCs. The results show that the mechanical properties depend to a large extent on the process parameters. The ...
Aufsatz
Joining of Contact Pins and Conductive Compounds via Injection Molding – Influence of the Flow Situation on the Electrical Contact Resistance
(2020-04-09)
While a lot of research can be found in the field of bulk resistance of carbon filled polymers, comparatively few papers focus on contact resistance between compound and metal contacts. Due to that small number of researches that deal with contact resistances, studies of the influence of injection molding conditions and parameters on the contact resistance are also very rare. In contradiction to that, these influences on bulk resistance have been studied. The objective of this work was to investigate the electrical ...
Aufsatz
Effects of aging on the stress-induced martensitic transformation and cyclic superelastic properties in Co-Ni-Ga shape memory alloy single crystals under compression
(2022)
Co-Ni-Ga shape memory alloys attracted scientific attention as promising candidate materials for damping applications at elevated temperatures, owing to excellent superelastic properties featuring a fully reversible stress-strain response up to temperatures as high as 500 °C. In the present work, the effect of aging treatments conducted in a wide range of aging temperatures and times, i.e. at 300–400 °C for 0.25–8.5 h, was investigated. It is shown that critical features of the martensitic transformation are strongly ...
Aufsatz
Microstructure of an additively manufactured Ti-Ta-Al alloy using novel pre-alloyed powder feedstock material
(2023-05-01)
Binary Ti-Ta and ternary Ti-Ta-Al alloys attracted considerable attention as new potential biomaterials and/or high-temperature shape memory alloys. However, conventional forming and manufacturing technologies of refractory based titanium alloys are difficult and cost-intensive, especially when complex shapes are required. Recently, additive manufacturing (AM) emerged as a suitable alternative and several studies exploited elemental powder mixing approaches to obtain a desired alloy and subsequently use it for complex ...
Aufsatz
Influence of ethylene oxide and gamma irradiation sterilization processes on the degradation behaviour of poly(lactic acid) (PLA) in the course of artificially accelerated aging
(2024-02-10)
To promote the application of bio-based materials in the field of medical technology, it is essential to conduct additional research, focusing on their long-term performance after sterilization. For this purpose, the study examines the aging behaviour of three poly(lactic-acid) (PLA) materials, sterilized with either ethylene oxide or gamma irradiation, over a two years aging period, in accordance with ASTM F1980-21. During these investigations, a direct correlation between moisture absorption and degradation progression ...