Assoc. Prof. Xu Li
Hubei Key Laboratory of Theory and Application of Advanced Materials Mechanics,School of Science, Wuhan University of Technology, China
Speech Title: Experimental Study and Characterization on the Mechanical Behavior of Uncured Rubber under the Planar Tensile Deformation
Abstract: The overall mechanical behavior of uncured carbon black filled rubber was investigated under planar tension at finite deformation. Experimentally, thin sheet specimens were manufactured and submitted to different scenarios of cyclic tensile loading. A non-contact optical technique, called Automated Grid Method, was employed to get the uniform deformation in the center region of rubber sample, while the displacement of whole field is heterogeneous in planar test. Consequently, the precise stress-strain responses at different strain rates were achieved. These results indicate the complicated properties of uncured rubber associating with hyper-elasticity, viscous flow, hysteresis and Mullins effect, which are almost dependent on strain rate. On the other hand, by decomposition of kinematics taking into account the hyper-elastic energy storage and plastic flow criterion, an improved parallel network model was put forward to characterize the nonlinear mechanics of this material. The fitted results consist well with the measured curves of both planar and uniaxial cyclic tests. Moreover, the prediction ability of constitutive model was evaluated by comparison with data issued from the single loadings and relaxation conditions. This work would be beneficial for gaining a satisfactory understanding on the multi-modes performance or mechanism of uncured rubber materials.
Biography: Xu Li is an associate professor (from 2015 to present) in the Department of Engineering Structure and Mechanics at Wuhan University of Technology, China. He received his BS (2005) in civil engineering from Shanghai University, MS (2008) & PhD (2018) in solid mechanics from University of Science and Technology of China. Besides, he worked one year as a visiting scholar in the Department of Mechanical and Aerospace Engineering at University of California San Diego, USA, during 2017-2018.
Prof. Li’s research interests mainly focus on the large deformation behavior and multiscale mechanics of soft smart composites or materials, for example rubber elastomer, hydrogel and shape memory alloy. He has undertaken and finished several research projects funded by Chinese government and industry, which concerns with performance prediction and property analysis of particle filled tire rubbers, characterization on mechanical adhesion between alloy wire and hyper-elastic elastomer, structural simulation and reliable evaluation on various polymeric composite products, etc. He has published more than 20 papers in journals such as Mechanics of Materials, Polymer Testing, Rubber Chemistry and Technology, Journal of Alloys and Compounds, Computational Materials Sciences, and so on.