Date of Award
Mechanical, Automotive, and Materials Engineering
Watt, Daniel F.,
Engineering, Materials Science.
CC BY-NC-ND 4.0
As polymers become more widely used by design engineers, it is important that the viscoelastic mechanical behaviour of these materials is properly taken into account. It is common that textbooks written on the viscoelastic properties of polymers include a section on the use of spring-dashpot models as a useful tool for the characterization of these properties. This thesis is an investigation into the ease of use, the reliability and the flexibility of three spring-dashpot analog models to rent the viscoelastic response of a polymer under different constraints of imposed loads and strains. In particular, this thesis describes attempts to take results from constant stress creep tests and constant strain stress relaxation tests and apply these results to a more varied four zone tensile test regimen. This anticipates a scenario where a design engineer might use creep and stress relaxation data in a numerical modelling program (e.g. finite element modelling) to predict behaviour in beading or some other loading-unloading sequence. In the present study, four different spring dashpot models were considered. One of these, commonly called the Burger's model, which is widely discussed in the literature, proved to be completely unsuitable for this application. A second, the Maxwell-Weichert model was somewhat more successful. Two new models were developed by the author that proved to be more useful. However, the general conclusion was that the models which could successfully simulate constant stress creep and constant strain stress relaxation cannot accurately predict the behaviour of a polymer in a more varied load-displacement test.Dept. of Mechanical, Automotive, and Materials Engineering. Paper copy at Leddy Library: Theses & Major Papers - Basement, West Bldg. / Call Number: Thesis1998 .K36. Source: Masters Abstracts International, Volume: 39-02, page: 0577. Adviser: Daniel F. Watt. Thesis (M.A.Sc.)--University of Windsor (Canada), 1998.
Karl, Michelle Marie., "Modelling the viscoelastic properties of low-density polyethylene." (1998). Electronic Theses and Dissertations. 2764.