液体火箭发动机端面密封用石墨材料内部缺陷检测工艺方法

介绍了石墨材料的制造工艺和缺陷类型,并结合液体火箭发动机端面密封的工作特性,阐明了端面密封用石墨材料内部缺陷检测的必要性。对目前通用的无损检测方法进行了对比分析,确定了适用于液体火箭发动机端面密封用石墨材料内部缺陷的X射线检测方法,并对X射线检测过程中图像灰度、对比度、电压、电流、滤片及积分时间等关键工艺参数的影响因素进行了对比分析,确定了石墨材料内部缺陷检测的工艺参数设置准则及高精度检测方法,实现了石墨材料内部孔隙的可视化仿真分析,并提出了一种基于图像处理的石墨材料气孔率统计计算方法,最终建立了液体火箭发动机端面密封用石墨材料内部典型缺陷的特征标样。

Internal Defect Detection Technology of Graphite Materialfor Liquid Rocket Engine Face Seal

The manufacturing process and defect types of graphite materials are introduced in this paper, combining with the working characteristics of the liquid rocket engine face seal, the necessity of testing the internal defect of graphite material for face seal is expounded. A comparative analysis is made on the present nondestructive testing methods, the X-ray detection method is the best for liquid rocket engines face seal. The key parameters of the X-ray detection such as gray scale, contrast, voltage, current, filter slice and integral time are compared and analyzed, then the process parameter setting rule and the high precision detection method of the internal defect inspection of graphite material are confirmed.And a visual simulation analysis of the internal space of graphite material is realized.And method for calculating the rate of porosity of graphite materials based on image processing.Finally the characteristics of graphite material internal defects typical of standard samples input forward of liquid rocket engine face seal are established.