双频振动载荷下带V形槽铝合金棒料的断裂行为

针对金属棒料低应力分离过程中裂纹萌生扩展速率低的问题，提出一种基于双频振动的加载方法，探究带V形槽7A09铝合金棒料的断裂行为。研究了双频振动对带V形槽金属棒料裂纹萌生扩展的作用机理，通过研发双频激振装置，对带V形槽7A09铝合金棒料进行了实验研究。实验结果表明，相对于单频振动加载方法，双频振动载荷能够大幅缩短带V形槽7A09铝合金棒料的分离时间，有效提高裂纹萌生扩展的速率与稳定性，棒料断面几何精度高。

Fracture Behavior of Aluminum Alloy Bars with V-shape Notchs under Dual Frequency Vibration Loads

Aiming at problems of low crack initiations and propagation rates in low stress separation processes of metal bars, a new method was proposed based on double frequency vibrations. This method was used to explore the fracture behaviors of 7A09 aluminum alloy bars with V-shape notchs. The mechanism of double-frequency vibrations on the crack initiations and expansions of V-shaped metal bars was given. Experiments of the V-shaped groove 7A09 aluminum alloy bars were carried out by developed dual-frequency exciting device. Experimental results show that compared with the single frequency vibration loading method, double frequency vibration load may shorten separation time of 7A09 aluminum alloy bars with V-shape notchs significantly, improve the crack initiation rates and stability of the expansion effectively, also the bar section geometric accuracy is high.