Development of Beam Monitoring Materials for 2-dimensional Beam-lntensity Monitoring of High lntensity Beams.

本项目的目的是利用离子束辐照诱导光子发射的氧化物材料，开发用于二维光束监测的光束监测材料。在用于常规光束监测的单片陶瓷（如氧化铝和硅板）中，无法观察到高强度光束的光子发射饱和和光束轮廓，并且由于光束加热而引起的热应力使板制动。本课题研制的光束监测材料克服了陶瓷监测材料的这些缺点。本课题的特点是将氧化陶瓷粉末分散金属应用于束流监测材料。在这种监测材料中，贱金属如铜和铝承担冷却和热应力机械强度部分，分散陶瓷粉末承担光束监测部分。本文介绍了这些监测材料的制备方法，高强度离子束辐照下的光发射性能和耐热性的估计。报告摘要如下：采用粉末冶金法制备了用于光束监测的氧化物分散金属。利用日本东北大学的动力加速器对氦离子束辐照响应进行了估计。研究了氧化物类型、氧化物粉末含量、粉末尺寸和基体金属对光子发射行为、耐热性和可加工性的影响。结果表明，含Cu 2 ~ 5%的氧化铝合金最适合用于高强度光束的二维光束监测。将合金固定在水冷台上，没有观察到光束加热引起的温度升高，即使在13MW/m2的光束载荷下也可以观察到二维光束轮廓。基于这些结果和讨论，得出了光束监测材料的材料设计概念和制造的基本条件。

The purpose of this project is to develop beam-monitoring materials for 2-dimensional beam monitoring using ion-beam irradiation induced photon emission from oxide materials. In the monolithic ceramics such as alumina and silica plates which are used for conventional beam monitoring, photon emission by high intensity beam saturates and beam profiles can not be observed and the plates brakes by thermal stress by the beam heating. Beam monitoring materials which were developed by this project overcome these weak points of these ceramics types of monitoring materials. Characteristic point of this research project is applying oxide-ceramic powder dispersion metals to beam monitoring materials. In this monitoring materials, base metal such as copper and aluminum takes parts of cooling and mechanical strength for thermal stress, dispersion ceramic powder take a part of beam-monitoring. This report describes fabrication methods of these monitoring materials, estimation of photo-emission behavior during high-intensity ion-beam irradiation and heat resistance. The summaries of the report are as follows ;Oxide dispersion metals for beam monitoring were fabricated by powder metallurgy method. Ion beam-irradiation response was estimated by helium-ion beam using a dynamitron accelerator at Tohoku University. Effects of oxide types, the contents of oxide powders, the size of powders and base metals on photon emission behavior, heat resistance and workability were studied. Based on these results showed that Cu containing 2 to 5% alumina alloys were the most appropriate to 2-dimensional beam-monitoring for high-intensity beams. Fixing the alloy on a water cooling stage, temperature increase by beam-heating were not observed and 2D beam profile could be observed even under beam-loading of 13MW/m2. Based on these results and discussion, the material design concepts and basic conditions for fabrication of beam-monitoring materials were obtained.