复合材料工件缺陷漏检的原因分析

Cause Analysis of the Composite Workpieces Defects Omission

利用x射线数字成像技术检测复合材料工件的内部质量，在相隔90°、两次检测时有缺陷漏检情况发生。借助于X射线层析成像（CT）技术，分析产生漏检的原因。结果表明，该复合材料工件存在检测不到夹杂缺陷的四个角度范围，分别是55°-60°，120°-125°，230°～235°，305°～307°，从检测的DR图像中不能发现缺陷，只能看见标记物。将工件准确旋转90°进行第二次检测，则能够发现标记物和缺陷；如果旋转的角度小于90°（在60°～77°范围内）或者旋转的角度大于90°（在105°-115°范围内），则从检测DR图像中观察不到缺陷，只能看见标记物，所以在进行第二次检测时。旋转角度不应为60°～77°或者105°～115°。

The use of X-ray digital imaging technology was used to detect internal quality of the composite workpieces, separated by 90°. Twice detection had defects omission. By means of X-ray tomography （CT） technology, the undetected causes were analyzed. The results show that the inclusion defects in the composite workpieces should not be detected in four angle ranges, which are 55°-60°, 120°-125°,230°-235°,305°-307°, defects can not be found from the detected image of digital radiography（DR）, only to see the markers. But the workpiece is rotated 90° accurately in the second detection, markers and defects can be found. If the rotation angle is less than 90° （in the range of 60°-77°） or greater than 90° （in the range of 105°-115°）, defect is not observed from the DR images except visible marker. So during the second test, the rotation angle should not be 60°-77° or 105°-115°.