基于PIPA技术的固体推进剂无损检测研究

Study on nondestructive detection in solid propellant based on PIPA

针对国内现有无损探伤方法无法检测固体推进剂微观缺陷的情况,引入光致正电子湮灭分析方法,即PIPA(Photon Induced Positron Annihilation)。该方法利用加速器产生的高能光子引发的正电子与固体推进剂作用来检测其缺陷,能在固体推进剂宏观缺陷出现前检测出其微观结构的变化。介绍了PIPA原理,并通过试验讨论了温度、拉伸速率及推进剂的力学性能等因素对利用PIPA进行固体推进剂探伤结果的影响,所得结论与固体推进剂的常规测试具有一致性,证明了PIPA用于固体推进剂无损探伤的可行性。

In considering that the micro defects can not be detected with present nondestructive detection methods,PIPA（Photon Induced Positron Annihilation） is introduced.The positrons created by the PIPA process are formed throughout the solid propellant and the defects in solid propellant could be detected by examining the annihilation of the positrons in solid propellant.With this method,the changes of microstructure could be inspected before the macro defects appear.The fundamentals and effects of different factors,including temperature,strain rate and the mechanical properties of solid propellant on the nondestructive detection to solid propellant are described accordimg to the experiment.The results of experiments are coincident with the regular tests,which proves its feasibility in nondestructive detection of solid propellant.