Process development and mold sampling for the production of highly oriented test specimens made of short-fiber-reinforced thermoplastic by injection molding

Bachelor- oder Master Thesis

Topic of the work

Short-fiber-reinforced thermoplastics are predominantly processed using the injection molding process, as this method enables the economical, high-quality and automatic production of components. Due to the flow conditions within the melt, however, a layer structure with different fiber orientations is created across the wall thickness. This local anisotropy makes it difficult to experimentally investigate material fatigue under oscillating load, as the orientation of the fibers has a considerable influence on the micromechanical damage mechanisms present. For the investigation of the fatigue behavior, a suitable injection molding tool is therefore to be developed with which it is possible to produce a tube geometry with a homogeneous, highly oriented fiber orientation. With a thesis at IKV, you have the opportunity to acquire comprehensive knowledge of the injection molding process and the development of injection molds and thus contribute to the further development of the process.

© IKV

The work is related to this research project

The fatigue mechanisms in short-fiber-reinforced plastics are not yet fully understood. For this reason, components fail prematurely, are replaced early or have to be over-dimensioned using large amounts of material in order to ensure operational stability. As part of the working group, you will contribute to research into material fatigue and thus support IKV in developing methods for safe dimensioning, taking sustainability into account.

Objective:

On the basis of numerical preliminary investigations, a mold cavity was determined so that a homogeneous, highly oriented fiber orientation distribution can be achieved in a tube specimen. Following these investigations, an injection molding tool was designed according to an established system for production and assembly and its components were manufactured. The aim of your work will be to assemble the Mould on the basis of the preparatory work, put it into operation and carry out an initial acceptance test. You will then systematically analyze the influences of the process parameters on the flow conditions of the plastic melt in the cavity and thus enable a stable manufacturing process for the production of homogeneous, highly oriented pipe test specimens. You will use X-ray computed tomography to analyze the orientation of the fibers in the test area of the specimen. In addition, the cavity geometry can be iteratively improved based on the emerging fiber orientation distribution. You will document the correlation you have determined between the system and process parameters, the flow conditions and the resulting fiber orientation distribution in a Bachelor’s or Master’s thesis.

Your task:

Your profile

• Engineering studies
• Independent, solution-oriented and creative way of working
• Interest in design work and existing CAD knowledge
• Ideally initial experience in injection molding
• Preferred study programs:
  Mechanical engineering / industrial engineering, specialising in mechanical engineering
  Automation technology
  General mechanical engineering
  Materials science
  Industrial engineering, specialising in materials and process engineering
  Applied Polymer Science