薄壁管预扭冲击拉伸实验装置的研制

材料在复合应力下的拉压或扭转行为常常与单轴拉压或者单轴扭转应力下不同,拉压以及扭转常体现出相互影响的特点。而复合应力下的塑性波可以有效地反映材料在复合应力下的本构行为特点。本文通过对霍普金森压杆进行改造,建立了一套薄壁管预扭冲击拉伸的实验装置,可以在薄壁管内产生拉扭耦合塑性波,并对率相关材料304不锈钢进行了薄壁管预扭拉伸实验研究,得到了该材料的拉扭耦合塑性波。结果表明,304不锈钢薄壁管的拉扭耦合塑性波具有明显的耦合快波和耦合慢波的双波结构,并且快波慢波之间没有恒值区间隔。同时也表明,该装置可以实现预期效果,并且可以有效避免薄壁管屈曲的产生。

Development of a Device for Impact Tension of Pre-torqued Thin Walled Tube

The behavior of material in tension, compression and torsion under combined stress condition is often different from the behavior under uniaxial tension, compression and torsion, and often exhibits some characteristics of mutual influence. The plastic waves produced under combined stress can effectively reflect constitutive behavior characteristics of matireal under combined stress action. In this paper, a device for impact tension experiment of pre-torqued thin-walled tube was established based on a reformed split Hopkinson pressure bar, which can generate coupled plastic waves of tension and torsion in thin-walled tube. Pre-torqued tension experimental study of thin-walled tube made of rate correlative material 304 stainless steel was carried out, the tension-torque coupled plastic waves of this material were obtained. Results show that the tension-torque coupled plastic waves of thin-walled tube made of 304 stainless steel present obvious double wave structure, i.e. coupled fast wave and coupled slow wave, and there is not constant interval between fast and slow waves. Above results also prove that this device can achieve the desired effect and avoid the buckling of thin-walled tube.