激光冲击在LY12CZ中形成冲击波的研究

Study on shock wave resulted from laser pulse shocking on surface LY12CZ

应用ＥＭＧ２０１ＭＳＣ准分子激光器通过石英压力传感器和２４４０瞬态存贮示波器并采用两种方式（瞬态存贮法和滚动法）测定了激光冲击ＬＹ１２ＣＺ中产生的冲击波。激光器的波长为１０６μｍ，脉宽为２８ｎｓ，输出功率密度为１０６×１０８Ｗ／ｃｍ２。按照压电转化原理，计算出ＬＹ１２ＣＺ中形成的瞬态冲击波的量值处于ＭＰａ级，并分析和计算了冲击波的衰减方程。

When a laser beam irradiates to the surface on a metal,the instantaneous energy accumulation makes a great number of metal atoms vapourous and form a shock wave propagating to the inner of materials.These reactions makes the microstructure and the propreties of the materials improved.In order to experimentally research the shock wave,the system composed of a quartz pressure transducer and a EMG201MSC excimer laser operating at 1060nm,pulse width 28ns,power density 1.06×10 8W/cm 2,is designed to measure the laser shock wave on the surface of LY12CZ aluminum alloy,using instantaneous storage method and rolling method with a 2440 instantaneous storage oscilloscope.The experimental results show that the pressure of laser shock wave is MPa order.Finally,the attenuating equation of laser shock wave has the expression of P =13.4 t -0.099 ,here the unit of P and t is MPa and ns respectively.