The University of Augsburg, Augsburg, Germany was founded in 1970 and is considered one of the new, modern universities of Bavaria. The university uses a Logitech PM5 Precision Lapping & Polishing system for the lapping and polishing of carbon fiber reinforced thermoplastic.
The Institute of Physics within the university has published a paper of their research on “Influence of residual thermal stress in carbon fiber-reinforced thermoplastic composites on interfacial fracture toughness evaluated by cyclic single-fiber push-out tests.” Their research has used cyclic thermal expansion measurements and cyclic single-fiber push-out tests on undirectional carbon fibre-reinforced thermoplastic composites, revealing process-induced residual thermal stress. Through this research they have proven that by annealing the composite above the glass transition temperature of the Polyphenylene sulfide matrix, the residual thermal stress can be reduced, due to structural relaxation processes.
The Logitech PM5 Precision Lapping & Polishing System was utilised to prepare the samples for the push-out tests. After the sample was cut from the material it was necessary for the sample to be thinned to a final thickness of between 30 and 60µm. After initial slicing the samples were thinned by a two-sided lapping process on the PM5. The PM5 allowed for a minimum thickness of 300µm to be lapped from each side of the sample. They have claimed of the process “A high surface finish with lowest difference in height between carbon fibres and the surrounding matrix was accomplished”.