应用红外热像技术检测木材孔洞缺陷

An experiment on application of infrared thermal imaging for non-destructive testing of wood defects

为了提高木材空洞缺陷的红外检测精度,采用空洞模拟手段,以6个含有不同径级的人工孔洞缺陷的色木试样为研究对象,应用人工红外灯和烘干箱法,研究孔径缺陷识别的最佳加热时间和最佳加热温度,探讨热源选择对不同孔径大小的试材检测效果的影响。研究结果表明:随着试样缺陷孔径的不断减小,最佳加热时间和最佳加热温度都逐渐减少;在一定孔径范围内热像图能较为准确的反映木材缺陷的位置及大小情况;随着试样缺陷孔径的不断减小,检测效果越来越不明显。

The purpose of this study was to improve the accuracy of infrared detection of timber cavity defects.Artificial holes with different diameters were drilled in 6 Acer mono samples to simulate the natural defects.Infrared light and drying oven were applied to study the optimal heating temperature and heating time for hole detection.The effect of heating source on the hole size detection was also discussed.The results showed that the detection of smaller holes demanded less heating time and lower temperature.In a certain hole size range,the location and the size of the holes could be accurately detected by the thermal images.The detection accuracy became lower as the hole diameters became smaller.