中国激光, 2018, 45 (11): 1102006, 网络出版: 2018-11-15
超声检测激光沉积制造TA15合金弱小缺陷的增强 下载: 682次
Weak Defect Enhancement in Ultrasonic Testing of Laser Deposition Manufactured TA15 Alloys
激光技术 图像增强 离散小波变换 水浸超声检测 激光沉积制造 laser technique image enhancement discrete wavelet transform immersion ultrasonic testing laser deposition manufacturing
摘要
提出了一种基于离散小波变换的算法,对超声检测激光沉积TA15合金图像中微小、低对比度的缺陷进行了增强。利用Penalized软阈值对缺陷的高频细节信息进行去噪,并通过Gamma变换提高缺陷低频信息的对比度。综合考虑信息熵和对比度,对多组样本进行了测试实验。研究结果表明,针对具有独特快速熔凝组织的激光沉积制件,所提算法比高斯滤波及模糊集增强理论具有更好的弱小缺陷增强能力。
Abstract
Based on the discrete wavelet transform, an algorithm is proposed to enhance the tiny and low-contrast defects in the ultrasonic testing images of the laser deposited TA15 alloys, in which the Penalized soft threshold is used to denoise the high-frequency detail information of the defects and the Gamma transform is used to enhance the contrast of the low-frequency information of the defects. Both the information entropy and the contrast are taken into account to test multiple groups of samples. The research results show that, as for the laser-deposited parts with a unique rapid solidification structure, the proposed algorithm has a better ability of weak defect enhancement compared with the Gaussian filtering and the fuzzy set enhancement theories.
李一波, 韩毅, 杨光, 钦兰云, 王超. 超声检测激光沉积制造TA15合金弱小缺陷的增强[J]. 中国激光, 2018, 45(11): 1102006. Li Yibo, Han Yi, Yang Guang, Qin Lanyun, Wang Chao. Weak Defect Enhancement in Ultrasonic Testing of Laser Deposition Manufactured TA15 Alloys[J]. Chinese Journal of Lasers, 2018, 45(11): 1102006.