| abstract |
A moderator for moderating neutrons, comprising a substrate (402) and a surface treatment layer (401) or a dry inert gas layer or a vacuum layer deposited on the surface of the substrate (402), wherein the substrate (402) is prepared from a moderating material by a powder sintering process using a powder sintering device so as to convert the powdery or compact powders into blocks, and the material of moderation comprises from 40 to 100% by weight of aluminum fluoride; the surface treatment layer (401) is a hydrophobic material; and the surface treatment layer (401) or the dry inert gas layer or the vacuum layer is used to isolate the substrate (402) from the water present in the environment where the substrate (402) is located. The surface-treated moderator can avoid the hygroscopic deliquescence of the moderating material in use, improve the quality of the neutron source and prolong its life. |