Nickel Powder:  Manhattan's secret ingredient

Nickel powders are widely used in industrial applications worldwide, such as rechargeable batteries, manufacturing and powder metallurgy. In some cases, nickel powders are used to add a magnetic feature to a particular material. Nickel can be used in electroplating and coinage industries as well. But there is more to nickel powder, and there is something that you have probably never heard about until now.

“Now I am become Death, the destroyer of worlds”

Oppenheimer quoting the Bhagavad Gita, after the successful atomic bomb test at Los Alamos

In 1942, more than 100,000 scientists were working on developing an atomic bomb in what is known as the Manhattan Project. The research recruited the greatest scientific minds and at the time was the largest collective scientific effort in history. The discovery of the neutron followed by that of nuclear fusion in uranium opened the possibility of a controlled nuclear chain reaction with uranium. Even though the most significant success was achieved by getting a chain reaction, enriched uranium would likely be needed to build the atomic bomb. George B. Kistiakowsky suggested the possibility of using gaseous diffusion to separate the isotopes and this is how “K-25 Project” was initiated. 

K-25 is a former uranium enrichment facility that was a part of the Manhattan Project aimed to research and produce the first nuclear weapon in human history. K-25 was used as a gaseous diffusion plant during for the duration of project to develop uranium enrichment. In gaseous diffusion the isotope was separated in stages. The gas passing each barrier was enriched in U-235. The uranium hexafluoride molecules were to pass the barrier which was built of porous metals. It turned out that finding the right metal was a challenging endeavour since uranium hexafluoride gas is extremely corrosive to metals.

Nickel Powder was the solution

In January 1944 scientists agreed on using a sintered nickel powder as a barrier. The barrier was used in a form of tubes and tubes were placed in more than 3000 barrel shaped cylinders which were used for transition of gases from previous stage to the next stage. The total length of nickel powder tubes used was greater than 6500 miles.

Production began in February 1945 and rapidly improved the quality of the product.  By April 1945 the plant achieved a 1.1% enrichment and some products produced in a next few months reached nearly 7% enrichment. K-25 achieved their maximum results in the early postwar period and became the prototypes for a new generation of gaseous and thermal diffusion plants.

https://en.wikipedia.org/wiki/K-25

https://en.wikipedia.org/wiki/Manhattan_Project

http://www.hcc.mnscu.edu/chem/abomb/page_id_35050.html