Crack detection in an aerospace turbine disk is essential for aircraft-quality detection.With the unique circular stepped structure and superalloy material properties of aerospace turbine disk,it is difficult for the ...Crack detection in an aerospace turbine disk is essential for aircraft-quality detection.With the unique circular stepped structure and superalloy material properties of aerospace turbine disk,it is difficult for the traditional ultrasonic testing method to perform efficient and accurate testing.In this study,ultrasound phased array detection technology was applied to the non-destructive testing of aviation turbine disks:(i)A phased array ultrasonic c-scan device for detecting aerospace turbine disk cracks(PAUDA)was developed which consists of phased array ultrasonic,transducers,a computer,a displacement encoder,and a rotating scanner;(ii)The influence of the detection parameters include frequency,wave-type,and elements number of the ultrasonic phased array probe on the detection results on the near-surface and the far surface of the aerospace turbine disk is analyzed;(iii)Specimens with flat-bottom-hole(FBH)defects were scanned by the developed PAUDA and the results were analyzed and compared with the conventional single probe ultrasonic water immersion testing.The experiment shows that by using the ultrasonic phased array c-scan to scan the turbine disk the accuracy of the detection can be significantly improved which is of greater accuracy and higher efficiency than traditional immersion testing.展开更多
To improve the processing efficiency and the quality of orbital milling hole of aerospace Al-alloy, the big-pitch influence on cutting force and hole quality was studied experimentally. First, a program based on horiz...To improve the processing efficiency and the quality of orbital milling hole of aerospace Al-alloy, the big-pitch influence on cutting force and hole quality was studied experimentally. First, a program based on horizontal lathe was proposed based on kinematics analysis of orbital milling. Then, the cutting force at different stages and the hole quality with different pitches were measured. Results show that the axial force and radial force increase with the pitch amplification during orbital milling. However, the axial force in the orbital milling hole is about 8—10 times smaller than that in the conventional drilling. The diameter error of milling hole is 48—93 μm, and the surface roughness of milling hole is 1.2—1.7 μm. Finally, an orbital milling device with big pitch was designed.展开更多
空间科学仪器广泛使用基于四象限光电探测器的太阳导行镜指向跟踪系统来实现对日精确指向控制。为满足对日指向高精度高稳定性需求,提出面向空间应用的四象限光电探测器筛选方法,研制针对四象限光电探测器的筛选系统。通过对比筛选试验...空间科学仪器广泛使用基于四象限光电探测器的太阳导行镜指向跟踪系统来实现对日精确指向控制。为满足对日指向高精度高稳定性需求,提出面向空间应用的四象限光电探测器筛选方法,研制针对四象限光电探测器的筛选系统。通过对比筛选试验前后四象限探测器的暗电流、响应度及象限响应度均匀性等参数变化,依据判别准则分析探测器的空间环境适应性,剔除可能存在的早期失效或性能差异变化较大的探测器。试验结果表明:研制的筛选系统具有高准确度,系统前端等效输入电流噪声为0.58 f Arms,通过筛选试验后依据评估标准最终优选的四象限光电探测器各通道暗电流绝对值最大值为6.08 p A,各通道的响应度变化最大值为0.716%,各象限响应度非一致性筛选前后变化最大值为1.24%。最终将该四象限探测器应用至太阳导行镜指向跟踪系统上,满足航天环境条件的使用要求。该筛选装置及筛选方法可实现对面向空间应用的四象限光电探测器的筛选,且对其他光电器件筛选具有借鉴意义。展开更多
作为载人航天工程中的组成部分,航天医监设备(aerospace medical monitoring devices,AMMD)是保障航天员的在轨生命安全和身体健康的重要支撑。以航天医监设备研制需要遵循的原则为基础,本文简要介绍了美、俄、欧空局医监设备的发展历程...作为载人航天工程中的组成部分,航天医监设备(aerospace medical monitoring devices,AMMD)是保障航天员的在轨生命安全和身体健康的重要支撑。以航天医监设备研制需要遵循的原则为基础,本文简要介绍了美、俄、欧空局医监设备的发展历程,详细阐述了我国载人航天载人飞船、交会对接、空间实验室等任务医监设备研制情况,描述了空间站任务医监设备发展成为包含心肺功能评估、体液指标检测、骨骼肌肉功能评价等在内的全方位医监设备体系,并展望了未来航天医监设备的发展方向。展开更多
基金This work was funded by the National Natural Science Foundation of China[Grant Nos.11664027,11374134]The National Natural Science Foundation of Jiangxi Province[Grant No.20161BAB216101]+1 种基金Key Laboratory of Non-Destructive Testing and Monitoring Technology for High-Speed Transport Facilities of the Ministry of Industry and Information Technology,Nanjing University of Aeronautics and AstronauticsThe Key Laboratory of Nondestructive Testing of Ministry of Education Nanchang Hang Kong University,Nanchang,China.
文摘Crack detection in an aerospace turbine disk is essential for aircraft-quality detection.With the unique circular stepped structure and superalloy material properties of aerospace turbine disk,it is difficult for the traditional ultrasonic testing method to perform efficient and accurate testing.In this study,ultrasound phased array detection technology was applied to the non-destructive testing of aviation turbine disks:(i)A phased array ultrasonic c-scan device for detecting aerospace turbine disk cracks(PAUDA)was developed which consists of phased array ultrasonic,transducers,a computer,a displacement encoder,and a rotating scanner;(ii)The influence of the detection parameters include frequency,wave-type,and elements number of the ultrasonic phased array probe on the detection results on the near-surface and the far surface of the aerospace turbine disk is analyzed;(iii)Specimens with flat-bottom-hole(FBH)defects were scanned by the developed PAUDA and the results were analyzed and compared with the conventional single probe ultrasonic water immersion testing.The experiment shows that by using the ultrasonic phased array c-scan to scan the turbine disk the accuracy of the detection can be significantly improved which is of greater accuracy and higher efficiency than traditional immersion testing.
基金Supported by National Natural Science Foundation of China (No.50975141 and No.51005118)Aviation Science Fund (No.20091652018 and No.2010352005)
文摘To improve the processing efficiency and the quality of orbital milling hole of aerospace Al-alloy, the big-pitch influence on cutting force and hole quality was studied experimentally. First, a program based on horizontal lathe was proposed based on kinematics analysis of orbital milling. Then, the cutting force at different stages and the hole quality with different pitches were measured. Results show that the axial force and radial force increase with the pitch amplification during orbital milling. However, the axial force in the orbital milling hole is about 8—10 times smaller than that in the conventional drilling. The diameter error of milling hole is 48—93 μm, and the surface roughness of milling hole is 1.2—1.7 μm. Finally, an orbital milling device with big pitch was designed.
文摘空间科学仪器广泛使用基于四象限光电探测器的太阳导行镜指向跟踪系统来实现对日精确指向控制。为满足对日指向高精度高稳定性需求,提出面向空间应用的四象限光电探测器筛选方法,研制针对四象限光电探测器的筛选系统。通过对比筛选试验前后四象限探测器的暗电流、响应度及象限响应度均匀性等参数变化,依据判别准则分析探测器的空间环境适应性,剔除可能存在的早期失效或性能差异变化较大的探测器。试验结果表明:研制的筛选系统具有高准确度,系统前端等效输入电流噪声为0.58 f Arms,通过筛选试验后依据评估标准最终优选的四象限光电探测器各通道暗电流绝对值最大值为6.08 p A,各通道的响应度变化最大值为0.716%,各象限响应度非一致性筛选前后变化最大值为1.24%。最终将该四象限探测器应用至太阳导行镜指向跟踪系统上,满足航天环境条件的使用要求。该筛选装置及筛选方法可实现对面向空间应用的四象限光电探测器的筛选,且对其他光电器件筛选具有借鉴意义。
文摘作为载人航天工程中的组成部分,航天医监设备(aerospace medical monitoring devices,AMMD)是保障航天员的在轨生命安全和身体健康的重要支撑。以航天医监设备研制需要遵循的原则为基础,本文简要介绍了美、俄、欧空局医监设备的发展历程,详细阐述了我国载人航天载人飞船、交会对接、空间实验室等任务医监设备研制情况,描述了空间站任务医监设备发展成为包含心肺功能评估、体液指标检测、骨骼肌肉功能评价等在内的全方位医监设备体系,并展望了未来航天医监设备的发展方向。
