Student paper

Crash-proof: high-speed tensile testing of technical thermoplastics

Project work

Investigate the crash behavior of injection-molded engineering thermoplastics.
Stuwi-Crashsicher_Hochgeschwindigkeitszugprüfung© IKV
In the high-speed train test (left), test specimens are subjected to crash-relevant loads. Using a high-speed camera, local strain can be analysed with high temporal resolution in the millisecond range (right).

Topic of the work:

Engineering thermoplastics are predominantly processed using injection molding, as this enables economical, automated and high-quality component production. Fiber reinforcement or foaming allows the mechanical properties to be specifically adapted and structural lightweight applications to be implemented in vehicle and appliance construction. The target variables here are weight-related stiffness and strength: fiber reinforcements increase stiffness and strength for the same weight, while foamed materials allow a reduction in weight with comparable strength. While the design is often based on quasi-static characteristic values, highly dynamic loads occur in the event of a crash, which must be taken into account in the design process. Your project work at IKV will give you an in-depth understanding of plastics as a material: You will learn about processing in injection molding, material testing and the determination of specific material parameters for crashes and how these determine component performance.

The work is related to this research project:

The work is part of a current research project that is investigating the stiffness and strength behavior of fiber-reinforced and foamed thermoplastics under crash loading. At present, these effects are usually only taken into account in component dimensioning by means of rough safety factors. The aim of the project is therefore to systematically investigate how the deformation and failure behavior changes under increased loading speeds. In particular, the influence of the material configuration, such as fiber orientation and foam morphology, should be taken into account. Practical dimensioning methods for industrial applications are to be derived on this basis.

Objective:

The aim of your work will be to determine material characteristics in the crash-relevant speed range. To begin with, you will learn the injection molding process and the specific variation of production parameters to produce different material configurations. On this basis, test geometries with varying fiber orientation and/or foam morphology are produced, which form the basis for further investigations. You extract suitable test specimens from these and carry out high-speed tensile tests. A high-speed camera is used to record and evaluate the local strain using video extensometry. You will learn the experimental investigation of material behavior under highly dynamic stress and the analysis of deformation processes in the millisecond range.

Your task:

  • Production of test specimens with varying material configurations using the injection molding process
  • High-speed train test at different speeds
  • Evaluation and analysis based on the images from the high-speed camera

Your profile:

  • Natural science or engineering degree (e.g. general mechanical engineering, industrial engineering, materials science, applied polymer science)
  • Independent and quality-conscious way of working
  • Interest in experimental work and scientific data analysis
  • Ideally initial experience in the field of mechanical testing

These are your benefits:

  • Learn scientific work in a motivated team with intensive supervision
  • Build on existing previous experience and expand it in a targeted manner
  • Learn the systematic collection, evaluation and interpretation of experimental data
  • Flexible start and rapid processing of the work are possible
  • Preparation for your Bachelor’s thesis

Has this vacancy piqued your interest? Then get in touch with me by e-mail or phone and send me your application documents.