Metallurgical Laboratory

The Metallurgical Laboratory or "Met Lab" was the Chicago-based part of the Manhattan Project – the Allied effort to develop the atomic bomb during World War II. It was part of the Metallurgical Project headed by Arthur H. Compton, a Nobel Prize laureate and Professor of Physics at the University of Chicago, the objective of which was to create an atomic bomb using plutonium. The Metallurgical Laboratory was established in February 1942. It produced the first controlled nuclear chain reaction on 2 December 1942 in Chicago Pile-1, built at the University's old football stadium, Stagg Field. In August 1942 its chemical section was the first to chemically separate a weighable sample of plutonium.

The world's first nuclear reactor, Chicago Pile-1, was soon moved by the lab to a more remote site in the Argonne Forest, where its original materials were used to build an improved Chicago Pile-2. Another reactor, Chicago Pile-3, was built at the Argonne site in early 1944. This was the world's first reactor to use heavy water as a neutron moderator. It went critical in May 1944, and was first operated at full power in July 1944. The Metallurgical Laboratory also designed the X-10 Graphite Reactor at the Clinton Engineer Works in Oak Ridge, Tennessee, and the B Reactor at the Hanford Engineer Works in the state of Washington.

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