用于分离式Hopkinson杆装置的一种先进气动发射机构

An Advanced Pneumatic Firing Mechanism for the Split Hopkinson Bar Equipment

为了提高分离式Hopkinson杆装置测试及其控制精度,基于一维应力波理论对Hopkinson杆测试原理进行了阐述,对测试中一维性和均匀性假设条件进行了深入分析。根据Hopkinson杆测试原理,提出了一套气推气的先进撞击杆发射装置。给出杆长与直径比大于40可保证一维性;试样中波来回反射3次以上可实现应力平衡及均匀性;气推气发射机构可以有效将0.5kg撞击杆在1MPa气压下发射65m/s;气推气发射机构与Hopkinson杆组成的测试装置操作简便、重复性好和控制精度高。

To improve the measuring and controlling precision of the split Hopkinson bar,based on one dimension stress wave theory,the measuring principle of the split Hopkinson bar is described; one dimension and uniform characteristic assumption in this technique is analysed in detail.According to the measuring principle of the split Hopkinson bar,an advanced pneumatic air-push firing equipment for the strike bar is developed.It is known that one dimension assumption can be achieved if a ratio of bar length to diameter is bigger than 40; stress equilibrium or uniform can be reached if loading stress wave inside a sample is reflected over 3 times; this pneumatic firing equipment can make weight 0.5 kg strike bar reach a 65 m/s velocity at 1 MPa air pressure.With the help of this pneumatic firing equipment,the split Hopkinson bar equipment can be easily operated,and has good repeated measuring characteristics and higher controlling precision.