ABSTRACT
The first uranium bomb exploded at the Semipalatinsk test site on October 18, 1951, was made from a few kilograms of 90%-enriched 2 3 5 U , produced at the first diffusion plant in 1949-1950 |84|. This happened 2 years after the detonation of the first Soviet plutonium bomb. From the very start the production of the Center was oriented to one consumer of highly enriched uranium - the Ministry of Defense 1971. Therefore, after producing highly enriched uranium from U F 6 , metallic
2 3 5 U was produced and used, like plutonium to make charge components for atomic bombs. Since the beginning of 1951 the gas-diffusion plant could produce approximately I kg of highly enriched uranium per day [84]. By that time at other PGU enterprises (at Plant No. 12 and NII-9) a technology was developed for producing items from metallic uranium to assemble uranium blocks for charging the first graphitemoderated uranium pile which operated since 1948 at Chelyabinsk-40 (Center No. 817). The properties of metallic uranium and plutonium were studied, the
technology was developed, and the appropriate production facilities were commissioned at Plant V of Center No. 817 for making components of atomic bombs both from metallic plutonium and from metallic uranium, after its 90%- enrichment in 2 3 5 U .
