• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2015, Vol. 51 ›› Issue (10): 1-7.doi: 10.3901/JME.2015.10.001

• 仪器科学与技术 •    下一篇

扫码分享

相控阵超声检测技术中的全聚焦成像算法及其校准研究

周正干1, 彭地1, 李洋1, 胡宏伟1, 2   

  1. 1. 北京航空航天大学机械工程及自动化学院 北京 100191;
    2. 长沙理工大学汽车与机械工程学院 长沙 410114
  • 出版日期:2015-05-15 发布日期:2015-05-15
  • 基金资助:
    国家自然科学基金资助项目(11202128)

Research on Baseline-free Damage Imaging Method Employing Omni-directional S0 Mode Magnetostrictive Transducers

ZHOU Zhenggan1, PENG Di1, LI Yang1 , HU Hongwei1, 2   

  1. 1. School of Mechanical Engineering and Automation, Beihang University, Beijing 100191;
    2. School of Automotive and Mechanical Engineering, Changsha University of Science and Technology, Changsha 410114
  • Online:2015-05-15 Published:2015-05-15

摘要: 相控阵超声检测技术中的全聚焦成像算法是一种基于全矩阵数据的虚拟聚焦后处理成像技术,因其具有精度高、算法灵活等优点成为近年来的研究热点。为了解决该算法在楔块耦合检测模式下的校准问题,介绍全矩阵数据及全聚焦成像算法的基本概念,通过对所存在问题的分析,建立双层介质的能量衰减模型;从指向性、透射和扩散三个方面分析声束传播路径上的能量衰减,计算衰减校准系数,提出基于校准的改进算法;分别采用未校准、平方根校准和自建模型校准的三种全聚焦算法对B型相控阵标准试块进行检测成像试验,从试验结果可以看出,平方根校准的算法能适当修正大声程的能量衰减,而自建模型校准的算法对于大声程、大偏转角的能量衰减都有较好的改善,使图像的能量更加均匀;此外,相比未校准和平方根校准,自建模型校准的算法具有更大的检测角度范围,有能力检测出大偏转角的缺陷。研究工作表明,校准后的全聚焦成像算法能够扩大检测角度范围、改善图像的能量均匀性,检测漏检率及缺陷定量误差得到有效降低。

关键词: 全矩阵数据, 全聚焦算法, 相控阵超声检测, 校准, 楔块耦合

Abstract: Total focusing method is an imaging approach using full matrix data which has become a research hotspot due to its advantages such as high accuracy, flexibility and so on. To solve the calibration problem in inspection with wedge coupled, full matrix data and its capture are described, a dual-medium energy attenuation model is established, three parts of calibration coefficient are given by analytical expressions which are directivity, transmission and diffusion attenuation, and a calibration based total focusing method is designed. Three images of the phased array test block type-B are formed using total focusing method. Experimental results show that it is good for the remote reflector with the calibration of root-square-distance, using the attenuation calibration model the attenuation caused by long path length and large deflection angle is better corrected and the energy of the image is more uniform. This calibration based total focusing method has the ability to detect the defects at large deflection angle. The research result shows that missing rate and sizing error can be reduced by calibration based total focusing method effectively.

Key words: calibration, full matrix data, total focusing method, ultrasonic phased array, wedge coupled

中图分类号: