Mechanical Properties of Hulless Barley Stem with Different Moisture Contents

Mechanical properties of hulless barley stems with different moisture contents (10.23%-43.14%) were investigated by using temperature sweep, frequency sweep, stress relaxation and creep tests of dynamic mechanical analyzer (DMA) in this study. Results showed a significant dependence of storage modulus, loss modulus and tan delta on moisture content. The data from stress relaxation and creep was fitted by using generalized Maxwell model and Burgers model. 5-element Maxwell model was better for describing relaxation behaviors of hulless barely stem compared with the 3-element Maxwell model. The peak values of loss modulus and tan delta both occurred at a low temperature when moisture content increased. The dynamic mechanical properties can provide useful information for the harvesting and processing of huless barely stem.