Measurement Of Dynamic Characteristic Of Thin Aluminum Board Under Laser Shock

The dynamic characteristics of thin board under the laser impact, means measuring the deformation time, deformation, deformation rate and strain rate of laser impacted specimen ,as well as belong to laser shock forming areas. Laser shock forming is a new technology and application which based on the development of laser shock, it shall be used for metal board forming. To study dynamic response and characteristics of laser shock forming, it can provide systems theory and experiment data for its material modification and forming development. In this paper, the author developed a new measuring instrument to study the various characteristics based on laser shock forming theoretical analysis, simulated and validated laser shock forming process with finite element analysis(FEA) software. The main contents and innovations are as follows:The author has developed a new measuring instrument using shading principles, the bulging part of the specimen shall block some laser beam from the semiconductor during the shock deformation, the quantity of blocked beam will cause changes on voltage signal of photodiode. To make a preliminary experimental study of the deformation time, extent, average speed and average strain rate, according to the changes on the voltage signal during specimen deformation.Based on the above experiments and according to the features of the LSF, the numerical simulation research is done to study the dynamic response and shaping laws of laser shock forming. How to choose the parameter of the FEM model is analyzed. The numerical simulation is used explicit dynamic analysis process, which can coincide with the high load and the quick structure response of laser shock forming, to improve the prediction accuracy. Numerical simulation is mainly used to study the transient response processes of laser shock forming, including displacement history, velocity, strain and strain rate. Comparing the simulated results with experiments, the precision and reliability are validated, which will be beneficial to the research of dynamic response of LSF.