US 12,411,076 B2
Stress and shock wave diagnosis fused LIBS optimization system and method
Jian Wu, Shaanxi (CN); Ying Zhou, Shaanxi (CN); Zhi Zhang, Shaanxi (CN); Mingxin Shi, Shaanxi (CN); Yan Qiu, Shaanxi (CN); Xingwen Li, Shaanxi (CN); Yuhua Hang, Shaanxi (CN); and Cuixiang Pei, Shaanxi (CN)
Assigned to XI'AN JIAOTONG UNIVERSITY, Shaanxi (CN)
Filed by XI'AN JIAOTONG UNIVERSITY, Shaanxi (CN)
Filed on Sep. 27, 2023, as Appl. No. 18/476,299.
Application 18/476,299 is a continuation of application No. PCT/CN2022/110506, filed on Aug. 5, 2022.
Claims priority of application No. 202210912279.5 (CN), filed on Jul. 29, 2022.
Prior Publication US 2024/0053257 A1, Feb. 15, 2024
Int. Cl. G01N 21/17 (2006.01); G01N 21/31 (2006.01)
CPC G01N 21/1702 (2013.01) [G01N 21/31 (2013.01); G01N 2021/1706 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A stress and shock wave diagnosis fused LIBS optimization method, comprising the steps of:
collecting a shock wave signal, a stress wave signal and a spectral signal of a detected object subjected to pulsed laser ablation under a current parameter, wherein the step of collecting the shock wave signal, the stress wave signal and the spectral signal of the detected object subjected to pulsed laser ablation under the current parameter comprises:
fixing a first piezoelectric ultrasonic transducer A1 on a position, away from an ablation point for a distance x, over a target surface of the detected object, and laterally collecting a shock wave signal Φ1; fixing a second piezoelectric ultrasonic transducer A2 on a position, away from the ablation point for a distance y, on the target surface, and measuring a stress wave signal Φ2 propagating along the target surface; then, connecting the first piezoelectric ultrasonic transducer A1 and the second piezoelectric ultrasonic transducer A2 to an oscilloscope, wherein x is a mounting distance of the first piezoelectric ultrasonic transducer A1, and y is a mounting distance of the second piezoelectric ultrasonic transducer A2; recording, by the oscilloscope, waveforms of the shock wave signal Φ1 and the stress wave signal Φ2 obtained after continuous N-pulse ablation under each parameter; and measuring a spectral signal Φ3 of a target element by a spectrometer;
pre-processing the spectral signal to obtain a spectral intensity of the detected object under the current parameter;
processing the shock wave signal and the stress wave signal to obtain a shock wave intensity and a stress wave intensity under the current parameter; and
adjusting optimization variables until optimization measurement and diagnosis of a spectral enhancement measure or system parameter are completed, wherein the step of adjusting optimization variables until optimization measurement and diagnosis of the spectral enhancement measure or system parameter are completed comprises:
selecting an initial optimization interval [a, b] of an optimization variable A, wherein a is the minimum value of the optimization variable A, and b is the maximum value of the optimization variable A; uniformly setting a total of n groups of optimization values, then, setting a shock wave intensity measured in an ith test as (E1)i, setting a stress wave intensity measured in the ith test as (E2)i, setting a spectral intensity measured in the ith test as (E3)i, and setting a value Si of the optimization variable A in the ith test as:
Si=a+(b−a)×(i−1)/(n−1),
wherein i=1,2, . . . n; and
starting a test from i=1, when (E3)2 measured in a second test is greater than or equal to (E3)1 measured in a first test, (E1)2≥(E1)1, and at the same time, (E2)2≥(E2)1, further increasing i with a step length of 1; or else, downwards or upwards replacing an optimization interval with [c, a] or [b, d], wherein c<a, and b<d; starting comparison again from i=1 until (E3)i+1 measured in an (i+1)th test is smaller than (E3)i measured in the ith test, (E1)j+1<(E1)i, and at the same time, (E2)i+1< (E2)i, and then, determining Si set during the ith test as an optimal value of the optimization variable A.