CT-Plus 320 kV: A High-Power Reflection X-ray Tube for Demanding Applications

We present the development and performance evaluation of a 320 kV CT-Plus open-type reflection microfocus X-ray tube (XWT-320-CT Plus) designed for high-power industrial computed tomography of strongly attenuating and large components. Key design improvements include a redesigned electromagnetic focusing system and a mechanically reinforced tube-head architecture, enabling stable, long-term operation at high accelerating voltages with significantly reduced focal spot drift and improved beam linearity. The resulting thermal and mechanical stability allows continuous high-power operation while maintaining micrometer-scale spatial resolution. CT experiments performed on a Diondo D2 metrology system demonstrate that, despite its lower nominal photon energy, the 320 kV microfocus X-ray tube achieves equal or superior resolution compared with a sealed 450 kV X-ray tube at identical magnification. This performance advantage is primarily driven by superior geometrical efficiency: the substantially shorter focus–object distance reduces the required focus–detector distance, increasing usable detector dose rate and enabling shorter scan times. Application-oriented studies on lithium-ion battery modules and steelattenuated test samples confirm that the combination of adjustable focal spot size, short projection geometry, and high thermal stability provides a highly efficient solution for high-resolution CT of dense industrial components.