Relaxation properties of particle filled coatings: Experimental study and modelling of a screw joint
2006 (English)In: Progress in organic coatings, ISSN 0300-9440, Vol. 55, no 2, 112-118 p.Article in journal (Refereed) Published
The present study describes the mechanical behaviour of powder coatings used under very high compressive loads in clamping force joints. Carboxyl functional polyester powder coatings cured with hydroxyl functional P-hydroxyalkylamides with variations in amount of filler have been studied. The coatings were subjected to relaxation tests in tension and in compression. The tests in compression were performed in specially designed tests developed to study the behaviour of powder coatings under compressive loads in clamping force joints. The relaxation results for the matrix were used in a unit cell in micromechanical finite element (FE) model to predict the homogenised viscoelastic properties of the particle composite. These constitutive properties were subsequently used to evaluate the behaviour on a macromechanical scale in a screw joint. The model corresponds well with experimental data at ambient temperature. When increasing the temperature above the glass transition of the coating, however, the model predictions and experimental data differ. Experiments in compression show a much lower relaxation its compared to the FE model. The relaxation simulations of the coating under compressive loads from screw joints showed a significant sensitivity to the Poisson's ratio of the polymer matrix. As the Poisson's ratio approaches 0.5, the matrix becomes hydrostatically incompressible, which resulted in a negligible relaxation of the coating at the screw joint.
Place, publisher, year, edition, pages
2006. Vol. 55, no 2, 112-118 p.
powder coating, mechanical properties, compression, screw joint, finite element modelling, relaxation
Manufacturing, Surface and Joining Technology
IdentifiersURN: urn:nbn:se:kth:diva-6079DOI: 10.1016/j.porgcoat.2005.09.008ISI: 000235627300006ScopusID: 2-s2.0-32144432885OAI: oai:DiVA.org:kth-6079DiVA: diva2:10686
QC 20100921. Conference: Coatings Science International Conference. Noordwijk, NETHERLANDS. JUN 26-JUL 01, 20052006-09-052006-09-052012-02-24Bibliographically approved