基于激光尾波加速的涡轮叶片高能X射线CT

发展微焦点高能X射线源技术是实现高精度高能工业CT突破的关键，基于激光尾波加速驱动高能轫致辐射源开展了微焦点高能X射线源产生以及对涡轮叶片高能CT成像研究。利用一台20 TW钛蓝宝石超快超强激光器，通过电离注入的方式获得了（140±44）pC的高能电子束，并使用1.5 mm厚钨靶产生了累积源尺寸为25 μm的高能轫致辐射X射线。利用该微焦点高能X射线源，采用基于压缩感知的CT重建算法，在获取较少角度投影（31个角度）的情况下，获得了对涡轮叶片叶榫结构的CT重建。

Micro-focus computed tomography for turbine blade based on all-optical bremsstrahlung source

Computed tomography is a major technique for nondestructive detection of internal defects of dense materials and large-size devices. It is widely used in material science, railway, aerospace, national defense, military industry and other industries. At present, conventional high-energy industrial computed tomography system uses the X-ray source based on traditional thermionic RF electron gun, which can only provide millimeter source size, thus limiting its imaging spatial resolution. A high-energy micro-focus X-ray source is the key means to realize high-resolution high-energy industry computed tomography. As an emerging accelerator technology, the laser wakefield accelerator is a promising candidate for the micro-focus high-energy industrial computed tomography. This article reports experimental results of a micro-focus X-ray source based on laser wakefield acceleration and a computed tomography for a turbine blade. Using a 20 TW Ti: sapphire laser system, an electron beam with a charge of (140±44) pC is generated through ionization-induced injection, and then an all-optical bremsstrahlung X-ray source with an accumulated source size of 25 μm is obtained by using a 1.5 mm tungsten target. Using this source, a preliminary compressed-sensing-based computed tomography for a turbine blade is performed.