A novel methodology for large strain under intermediate strain rate loading

Polymer Testing

J. Li¹  Q. Deng¹  H. He²  Y.G. Miao²  C.X. Wang²  K.X. Weng³ 

[1] Shaanxi Key Laboratory of Impact Dynamics and its Engineering Application, School of Aeronautics, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China;Joint International Research Laboratory of Impact Dynamics and its Engineering Applications School of Aeronautics, Northwestern Polytechnical University, Xi'an, Shaanxi, 710072, China;State Key Laboratory for Strength and Vibration of Mechanical Structures, Department of Engineering Mechanics, School of Aerospace Engineering, Xi'an Jiaotong University, Xi'an, Shaanxi, 710049, China;

关键词: Intermediate strain rate;    Large strain;    Hopkinson bar;    Dynamical behavior;   

DOI  :  

来源: DOAJ

【 摘 要 】

Hopkinson bar has already worked to measure mechanical properties of materials under high strain rates, but it fails to conduct intermediate strain rates loading with considerable deformation. Thereby, a methodology is proposed for achieving enough large strains under intermediate strain rates. The experimental system based on it is then constructed: a striker bar with same length as incident bar is selected to generate continuous stress wave loading, and a long polymethylmethacrylate bar is preferred as the transmitted bar to guide and record transmitted signals. Thus, loading stress wave is achievable with a nearly constant amplitude and an infinite loading duration. The involved data interpretations are deduced, and verified both theoretically and experimentally. Its measurement capacity is confirmed by loading a thermoplastic polyurethane, and maximum strains up to 12% and 65% under strain rates of 40/s and 270/s, respectively. Finally, the involved influences and factor sensitivities are analyzed for enough experimental accuracy and extensive measurements.

【 授权许可】

Unknown