单晶高温合金X射线衍射斑点自动识别算法研究  

Study on Automatic Identification Algorithm for X-ray Diffraction Spots of Single Crystal Superalloy

作　　者：张哲[1,2,3] 朱锦霞[1,2] 庄凯[1,2] 谢光[4] 秦秀波[1,2] 魏存峰[1,2] 

机构地区：[1]中国科学院高能物理研究所,北京100049 [2]北京市射线成像技术与装备工程技术研究中心,北京100049 [3]中国科学院大学,北京100049 [4]中国科学院金属研究所,沈阳110016

出　　处：《CT理论与应用研究（中英文）》2017年第4期447-455,共9页Computerized Tomography Theory and Applications

基　　金：中国科学院科研装备研制项目(292016YZB03);科技部重大仪器设备研制专项项目(2013YQ03062902);国家自然科学基金大科学装置联合基金重点项目(U1332202)

摘　　要：单晶高温合金展现出优越的抗疲劳性能和高温蠕变性能,广泛应用于航空发动机和燃气轮机的热端部件。但是,其制备过程中会产生晶体取向偏离、杂晶等缺陷。目前国际上已经普遍使用X射线劳埃衍射技术对单晶叶片的晶体缺陷进行无损检测,但是这种检测方法主要依赖人工识别,效率低,结果可重复性差,不适合批量化检测。本文结合工程需要,提出对劳埃衍射斑点进行自动识别的算法,主要包括衍射图样的预处理、轮廓检测、轮廓形态筛选及轮廓符合检测等。该算法能够自动检测出衍射图样上的衍射斑点,并最终给出斑点的位置坐标数据及其误差。根据衍射斑点的位置,通过衍射分析算法,计算出单晶叶片上的晶体取向,并最终对叶片的晶体缺陷给出综合评价。Single crystal superalloy has been widely used as hot components of aeroengine and gas turbine for its good anti-fatigue performance and high temperature creep property. At the same time, the defects like crystal off-orientation and mixed crystal would be produced during the manufacture of single crystal superalloy. Nowadays, Lane X-ray diffraction method is already widely used for nondestructive testing of these crystal defects on single crystal turbine blades all over the world. However, this method is not appropriate for mass testing as a result of its high dependency of manual identification, low efficiency and weak repeatability of the result. This article presents an automatic identification algorithm addressed on Laue X-ray diffraction spots patterns based on practical engineering needs, including pre-processing of diffraction pattern, contour detection, shape filtering of contours, and contour coincidence check. This algorithm can automatically find out spots on diffraction patterns, and offer their positions with measurement errors. Finally, the crystal orientation of the tested sample can be calculated based on these positions of spots with diffraction analysis method and so can those crystal defects on tested turbine blades sample be evaluated.

关 键 词：单晶高温合金 晶体取向 X射线衍射 自动识别算法 

分 类 号：TG132.3[一般工业技术—材料科学与工程] TP391.41[金属学及工艺—合金]