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It is well-known that aviation alloys of different grades show large differences in mechanical properties. At present, alloys must be strictly distinguished in the manufacturing plant because their close appearance and density are easily confused In this work, the wavelet transform (WT) method combined with the least squares support vector machine (LSSVM) is applied to the classification and identification of aviation alloys by laser-induced breakdown spectroscopy (LIBS). This experiment employed six different grades of aviation alloy as the classification samples and obtained 100 sets of spectral data for each sample. This research included the steps of preprocessing the obtained spectral data, model training, and parameter optimization. Finally, the accuracy of the training set was 99.98%, and the accuracy of the test set was 99.56%. Therefore, it is concluded that the model has superior generalization capacity and portability. The result of this work illustrates that LIBS technology can be adopted for the rapid identification of aviation alloys, which is of great significance for on-site quality control and efficiency improvement of aerospace parts manufacturing.

In order to measure the angle variation property of the mechanical-electrical structure in the system integration measurement and environmental experiments, a laser two-dimensional angle dynamic measurement system using the optical auto-collimation principle is developed, which can achieve the high precise and real-time measurement. The experiments indicate that the angle measurement precision is less than 10 second, the measurement range is within ±0.5 degree and the measurement rate is 1 KHz. The developed system provides a new technique for the high precision and rate measurement of the two-dimensional small angles.