【作者】 薛青； 沈乐天； 陈淑霞； 白以龙；

【Author】 Xue Qing,Shen Letian,Chen Shuxia,Bai Yilong (Institute of Mechanics,Chinese Academy of Sciences,Beijing,100080)

【机构】 中国科学院力学研究所；

【摘要】 分析了反复加载现象及其对变形微结构的影响,介绍了对现有标准Hopkinson扭杆的改进。改进后的新型Hopkinson扭杆是具有特殊设计的加载头和传动器的四杆系统。它完全消除了应力波的反复加载效应。实现了过程的单脉冲加载。改进前后的实验波形和变形局部化微结构形态的比较证实了改进的有效性。更多还原

【Abstract】 The loading reverberation is a multiple wave effect on the specimen in the split Hopkinson torsional bar(SHTB).It intensively destroys the microstructural pattern produced by the first loading pulse.This paper discusses this phenomenon and its effects on the deformed microstructure.A thorough-going modification of the SHTB is introduced, which involves attaching two unloading bars at the two ends of original clutches. The new four bar system eliminates the effects of the loading reverberation and provides the single wave pulse loading porcess.The wave recording results and the post mortem observation of the microstructure in shear banding highly support the effectiveness of the modified version.更多还原