Design And Experimental Study Of Fast Real-Time Detection System For Laser Cold Machining Holes

Femtosecond laser manufacture technology compared with traditional laser processing technology,because of short laser pulse width and the exceeding high instantaneous power,has unique advantages in the industrial processing,etc,especially using femtosecond laser processing,with holes on the aeroengine turbine blade is no recast layer,high machining quality and efficiency.However,due to the multiple cavities inside the turbine blade of the engine,it is very easy to cause back wall damage in the process of hole making.Therefore,real-time detection of hole penetration state is of great significance to prevent back wall damage.In this paper,based on femtosecond laser cold working principle,the analysis of the interaction between laser and materials produced on the basis of the thermal effect and the optical effect,for the laser system of cold working hole caused by testing not in time to carry on the back wall in the process of injury problems,this study designed a set of furnish system used in laser hole through rapid real-time detection system,which can improve the efficiency of laser drilling and the ability of real-time detection of hole processing.The system mainly includes four parts:laser emission module,photoelectric detection module,data acquisition module and FPGA control module.According to the system requirements to complete the main device related parameter design,calculation and selection.The interface of upper computer is designed,which can get the data acquisition,waveform display and waveform measurement of real-time detection signal.The system can get the communication between upper computer and lower computer FPGA control module through serial communication.The FPGA control module analyzes and judges the real-time detection signal by using the condition of hole penetration threshold,and feeds back the corresponding information to the laser controller in the form of pulse signal.System in xi 'an by laser light machine manufacture center of Chinese Academy of Sciences to carry out the experimental verification,the hole through detailed threshold judgment conditions were determined,and compared the experiment.Industrial CT detection was carried out on the real-time drilling results using the developed detection system.The results showed that the system could detect the hole penetration quickly and in real time,and there was no damage on the back wall of the processed hole.The detection time of the developed detection system was 3.78?s,and the penetration judgment time was 1.4.It is verified that the detection system designed in this study can get the rapid real-time detection of hole penetration and reach the expected requirements.The research results show good practical application value for enhancing the quality and efficiency of hole processing.