应用激光, 2014, 34 (6): 562, 网络出版: 2015-01-13
激光冲击波加载AZ31B镁合金薄板动静态响应实验研究
Experimental Research of Dynamic and Static Respond of AZ31B Magnesium Alloy Sheet by Laser Shock Wave
AZ31B镁合金 压电波形 动静态响应 残余应力 AZ31B magnesium alloy piezoelectric waveforms dynamic and static respond residual stress
摘要
为分析激光冲击AZ31B镁合金薄板背面的动态响应与残余应力分布规律,采用PVDF贴片传感器对冲击波进行测量得到压电波形与动态应变响应曲线,X射线衍射仪对薄板背面冲击区域中心与其边界点冲击前后残余应力进行测量,结合冲击波的传播规律,解释了应变变化对残余应力变化的影响。结果表明,冲击波从冲击区域向冲击区域外的传播过程中,能量衰减明显。动态应变响应曲线类似正弦曲线,冲击区域在弹塑性双波加载时动态应变骤然增高,随后波动上升,最终的静态应变呈现拉应变与检测出的残余应力变化规律相符,冲击区域边缘的动态应变响应相较冲击区域变化缓和,弹塑性双波的卸载与加载过程并未引起动态应变的大幅突变,静态应变变化不大与残余应力的变化规律一致。
Abstract
To analyze the dynamic respond of laser shock wave and distribution of residual stress on the back of AZ31B magnesium alloy sheet, the laser induced shockwave was measured by PVDF patch sensors and then piezoelectric waveforms and dynamic strain curves were got, meanwhile, the residual stress of shock spot and its boundary was measured before and after LSP by x-ray diffraction. The effects of dynamic strain on the residual stress changes were explained combined with shock wave propagation characteristics. The results indicate that the energy decay significantly from shock spot to its boundary. Dynamic strain curves are similar to the sinusoidal, dynamic strain of the shock spot suddenly increase when elastic and plastic wave loading and then rise fluctuatively. The static strain present tensile strain finally and correspond to the residual stress variation. The dynamic strain response is alleviate outside the shock spot. The unloading and loading process of the double waves doesn’t cause mutations in dynamic strain curve, so the residual stress changes little and correspond to the residual stress variation.
印成, 冯爱新, 曹宇鹏, 何叶, 庄绪华, 陈风国, 吕豫文, 吴浩. 激光冲击波加载AZ31B镁合金薄板动静态响应实验研究[J]. 应用激光, 2014, 34(6): 562. Yin Cheng, Feng Aixin, Cao Yupeng, He Ye, Zhuang Xuhua, Cheng Fengguo, Lv Yuwen, Wu Hao. Experimental Research of Dynamic and Static Respond of AZ31B Magnesium Alloy Sheet by Laser Shock Wave[J]. APPLIED LASER, 2014, 34(6): 562.