中国先进研究堆中子束应用关键技术及若干科学问题立项报告

Project Report of Neutron Beam Application on China Advanced Research Reactor

该研究的研究内容涵盖物理、化学、材料和工程等领域,拟解决以下3个方面的关键科学问题:(1)中子散射关键技术方法研究;(2)新型功能材料结构和性质关系的中子散射研究;(3)工程部件应力分布和中子成像的方法学研究。为此,项目设置6个子研究:(1)反应堆中子束优化及特殊样品环境研究;(2)单晶和多晶新材料的中子衍射研究;(3)强关联体系中原子与自旋动态的中子散射研究;(4)磁性材料的中子散射研究;(5)中子应力三维无损深度测量技术研究;(6)中子在物质中的衰减与中子成像研究。

Nowadays to study the relation between structures and properties of materials is one of the main tasks in Physics, Chemistry, material science and others research fields, and it is a usual way to get the information using particles interaction with matters, among which X ray and neutron are two basic ones. It is well know that the interaction principle of neutrons and photons with atoms is quite different, so more information will be obtained using both complementary tools. The neutron has the following properties： no charge, low energy, inherence magnetic moment, deep penetration, sensitivity on light element （such as H, C, N, O, etc）, distinguishability on isotopes （such as 7Li, 11B etc.） and near neighbor elements （such as Mn, Fe and so on）. So neutron scattering technique can not only study the crystal structure, but also obtain the magnetic structure information; not only investigate the static microstructure of materials, but also prove the rel iabil ities of theoretical models. CARR is expected to be critical in 2009, 60 MW and 8×1014N/（cm2 · S -1） unperturbed thermal neutron flux make it standing on an international advanced level. Using the four circle, powder, residual stress neutron diffractometers and neutron imaging instrument at CARR, in this project studies focus on three aspects： （1）the methodology study of neutron scattering technique; （2）the neutron scattering study on the relation between the structures and properties of novel function materials; （3）studies of the residual stress distribution in engineering components and the methodology of neutron imaging. Six topics are set as following： （l）Optimization on reactor neutron beam and studies on special sample environment; （2）Atomic and spin dynamics in strongly correlated system studied by neutron scattering; （3）Neutron Diffraction Study on Novel Crystal Materials; （4）Neutron scattering study on magnetic materials; （5）Neutron Diffraction Study on Three-Dimensional Nondestructive Deep Measurement of The Residual Stress; （6）Study on neutron attenuation in matter and neutron imaging.