Fusion bonding of reinforced thermoplastic

McGregor, Iain James (1987) Fusion bonding of reinforced thermoplastic. PhD thesis, University of Glasgow.

Abstract

A laboratory technique developed to produce fusion joints under carefully controlled conditions is described The technique was used to manufacture single-lap specimens from the reinforced thermoplastic APC-2, and the influence of processing temperature and surface degreasing on joint strength is presented The influence of laminate type, testing rate, bondline thickness and overlap length on joint strength were investigated, and the results from these tests are presented In order to enable mathematical modelling of fusion joints to be carried out, the shear stress-strain curve of the reinforced thermoplastic matrix, PEEK, was measured using the thick adherend specimen This curve is presented along with an analysis of the thick adherend specimen failure surface using scanning electron microscopy The influence of matrix viscosity on control of bondline thickness is also discussed The mathematical model of Hart-Smith was used to predict joint strength His theoretical analysis for the prediction of adherend failure was modified to consider the strain distribution in the composite adherends rather than stress distribution, and the derivation of this is presented A bi-elastic model for the prediction of adhesive shear failure was developed, and a comparison is made with the results from Hart-Smith's elastic-plastic analysis From the theoretical analyses, failure curves are presented for the three dominant failure modes of single-lap joints These are plotted as failure load/width against overlap length, and a comparison is made with the experimental results for the influence of overlap length and bondline thickness on joint strength for several laminates The influence of adherend thickness on predicted joint strength is also considered Finally, the work conducted into the development of a practical technique for producing fusion joints in APC-2 is presented The technique uses a direct heating method to heat the bondline through the thickness of the composite, and, therefore, a discussion is conducted into the effect of processing on the adherend material as well as the influence of processing parameters on joint strength.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Materials science, Plastics
• Date of Award: 1987
• Depositing User: Enlighten Team
• Unique ID: glathesis:1987-76684
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 19 Nov 2019 13:54
• Last Modified: 19 Nov 2019 13:54
• URI: https://theses.gla.ac.uk/id/eprint/76684