Elastic recovery and viscoelastic behavior of Agave americana L. fibers

The aims of this work were to study the viscoelastic behavior and the elastic recovery of Agave americana L. fibers. The results were considered in the context of an earlier study examining the mechanical properties of this natural fiber. Comparative investigations among three types of fiber extraction were made: raw fibers manually extracted, fibers extracted in distilled water, and fibers extracted in seawater. Two different approaches were used. The first approach considered structural effects by studying the changes of structure at different levels. In this case, atomic and molecular effects were taken into account. To further characterize the mechanical behavior of Agave americana L. fibers, a rheological constitutive model was developed using data from axial tension tests. The best model to explain the viscoelastic behavior of Agave americana L. fibers was the modified generalized Maxwell model. The values obtained for elastic recovery were influenced by the test conditions such as studied in this work: type of extraction, relative humidity, time for which the specimen was held at constant strain. The recovery curves of raw fibers and distilled water extracted fibers were very close to each other, while seawater extracted fibers had the best elastic recovery of any of the fibers tested. The study of the surface morphology by scanning electron microscopy contributed to a greater understanding of the fibers' mechanical behavior and in particular their elastic recovery.