Authors:Cai Shanyu, Sun Yuhua, Gao Wanshan, and Wei Barhong
In recent years, -particle surface applicators (such as32P,90Sr) have been widely used in treating some diseases of dermotology, ophthalmology, otolaryngology etc. in China. The powder metallurgy and metal rolling technology of strontium-90/yttrium-90 () sources and the manufacture process of90Sr/90Y surface applicators are described in this paper. For this kind of radioactive sources, the strontium-90 insoluble compound is incorporated in a silver matrix which is sandwiched between the gold (or silver) face and the silver backing. The external surface of strontium-90 foil source is then protected by palladium or tungsten-nickel alloy coating. The characteristics of strontium-90 surface applicator are of uniform dose rate, small self-absorption and safety in use, so it can satisfy the requests of medical care.