基于红外无损检测的非金属材料粘贴缺陷识别

Identification of Adhesive Defects of Non-metallic Materials Based on Infrared Non-destructive Testing

非金属材料粘贴结构的脱粘现象可影响其性能,使用红外无损检测技术可对粘贴缺陷进行有效的识别。首先研究了基于红外无损检测技术的粘贴缺陷边界特征,确定了使用温度梯度极值判断粘贴缺陷边界位置的定量分析方法;结合该特征,采用了Canny边缘检测算法对数值模拟的粘贴缺陷模型进行缺陷边界识别。同时使用该算法对实验数据进行识别,针对识别结果出现的边界模糊、噪点多等问题,提出了筛选出所有“疑似边界”以保留“弱边界”的改进算法。结果表明,改进后的Canny算法能够提高红外无损检测粘贴缺陷的完整性和准确性。

The debonding of non-metallic materials can affect their performance,and infrared nondestructive testing can identify adhesive defects effectively.The boundary feature of adhesive defects is first investigated in this study based on infrared non-destructive testing;subsequently,a quantitative analysis method for identifying the boundary position of adhesive defects using the extreme value of a temperature gradient is obtained.Next,the Canny edge detection algorithm is used to identify the defect boundary of an adhesive defect model by numerical simulations and to identify experimental data simultaneously.For problems such as blurred boundaries and noise for recognition results,an improved algorithm for filtering out all“suspected boundaries”to preserve the“weak boundary”is proposed.The results show that the improved Canny algorithm can improve the integrity and accuracy of identifying adhesive defects from infrared non-destructive testing.