3D打印镂空结构缺陷X射线CT检测

Defect testing for 3D printed hollow structure using X ray CT technique

3D打印镂空结构在减重方面具有重要的工程意义.基于X射线CT成像检测技术,文中研究了光敏树脂材料3D打印镂空结构缺陷的识别及定量化检测问题.通过研究X射线管电压及管电流对CT成像信噪比、清晰度及对比度的影响,获取了优化的检测工艺参数;在获取的CT图像中对缺陷尺寸进行了无损测量,采用破坏性试验进行了验证,并分析了测量误差.结果表明,采用优化的检测参数能有效提升检测灵敏度及检测精度,文中试验条件下可有效识别直径0.1 mm的气孔,缺陷尺寸测量平均相对误差不超16%.

Hollow structures fabricated by 3 D printing have important engineering significance in weight reducing.Using X-ray computed tomography(CT) technology.This paper is concerned with the problem of non-destructive testing of 3 D printed hollow structure with photosensitive polymer resin is studied. By studying the effect of X-ray tube voltage and current on the signal-to-noise ratio, sharpness and contrast of CT images, the optimized parameters for the experiments were obtained. The defect size were measured nondestructively in the acquired CT images. The non-destructive tested results were verified by destructive testing, and the measured error was analyzed. The results show that the testing sensitivity and accuracy can be improved effectively by using the optimized testing parameters. Under the experimental conditions, the gas pore with a diameter of 0.1 mm can be identified, and the size of the defects can be measured with an average relative error of 16%.