Fmit-The Fusion Materials Irradiation Test Facility

One of the major problems facing future fusion reactor designers will be the choice of materials with which to build the containment vessel. Although hundreds of millions of dollars are being invested in fusion research around the world, and optimism exists that fusion power will become available by the end of the century, we cannot today build a practical power plant because we cannot positively specify a material that will withstand the irradiation of high flux, 14-MeV neutrons for adequate lengths of time. High rates of helium and hydrogen production, transmutation, and extensive irradiation damage all result when materials are subjected to 14-MeV neutrons. It is essential now that we build a machine that can produce these neutrons by means other than fusion and at flux levels sufficiently high so that material assessments can be made in time periods substantially shorter than projected end-of-life spans under normal operating conditions. Such a machine can be used to support all facets of the fusion energy program, whether it be magnetic or inertial confinement that eventually proves to be most effective. This machine must be put into operation by the mid-1980's so that preliminary materials data can be made available by 1990 to confirm reference material choices and provide a basis for development of advanced materials.