DEVELOPMENT OF SR-90 Y-90 (BETA) SURFACE APPLICATORS BY POWDER METALLURGICAL TECHNOLOGY/

In recent years, beta-particle surface applicators (such as P-32, Sr-9 0) have been widely used in treating some diseases of dermotology, oph thalmology, otolaryngology etc. in China. The powder metallurgy and me tal rolling technology of strontium-90/yttrium-90 (beta) sources and t he manufacture process of Sr-90/(50)(V) under bar surface applicators are described in this paper. For this kind of beta radioactive sources , the strontium-90 insoluble compound is incorporated in a silver matr ix which is sandwiched between the gold (or silver) face and the silve r backing. The external surface of strontium-90 foil source is then pr otected by palladium or tungsten-nickel alloy coating. The characteris tics of strontium-90 surface applicator are of uniform dose rate, smal l sell-absorption and safety in use, so it can satisfy the requests of medical care.