Laser shock peening quality on-line monitoring method based on time window energy attenuation coefficient

Abstract

The invention discloses a laser shock peening quality on-line monitoring method based on a time window energy attenuation coefficient. The method carries out the fusion of two channels of synchronously collected acoustic emission signals through dynamic acoustic emission signals generated in a laser shock processing process to obtain an arithmetic mean value, on the other hand, by means of the acoustic signal attenuation theory, time domain windowing processing is carried out on the acoustic emission signals, window signal energy is calculated, an exponential attenuation function y=aebx is adopted for fitting the acoustic emission signals, the exponential attenuation rule of the acoustic emission signals in a workpiece material can be better revealed, the physical significance of the acoustic emission signals is improved, and a fitting parameter b is extracted to serve as a characteristic parameter. The method has strong characterization capability and robustness, and is helpful for improving accuracy and stability in actual production application. The method is simple, convenient and rapid in feature extraction, good in state response, stable, reliable, low in cost and high in engineering practicability, and provides an efficient technical implementation way for online monitoring of the laser shock peening quality.

Description

technical field [0001] The invention belongs to the technical field of laser shock peening processing and intelligent detection, and specifically relates to an online monitoring method of laser shock peening quality based on time window energy attenuation coefficient. Background technique [0002] Laser Shocking Peening (LSP), also known as laser peening, is a new technology for metal surface strengthening. The laser beam with short pulse and high power density induces the energy absorbing layer on the surface of the workpiece to generate high-temperature and high-pressure plasma shock waves, and then produces a certain depth of residual compressive stress on the surface of the processed workpiece, which greatly improves the fatigue resistance and wear resistance of the workpiece. Performance, etc. Compared with traditional surface modification technologies such as shot peening and rolling, laser shock peening technology has outstanding advantages such as no contact, no heat...

AI Technical Summary

Problems solved by technology

However, the existing on-line monitoring methods do not theoretically analyze the dynamic change relationship between the acoustic emission signal and the processed workpiece tissue, extract features that can reflect the dynamic attenuation of the acoustic emission signal to characterize the quality of laser shock strengthening, but directly extract the The amplitude, frequency and other characteristics of the generated acoustic wave signal, so the online monitoring process is vulnerable to noise interference, the reliability and accuracy are low, and the robustness is weak, so it is difficult to popularize and apply in actual production

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