The national high magnetic field laboratory builds and uses various high
field magnets for fundamental research. In building high field magnets, a
variety of high strength composites are required because of the Lorentz
stresses generated by high field exceeding the strength of most of the
materials, particular conductors. For example, a field of 60 T can generate
a magnetic pressure that corresponds to a stress in the conductor of 1.5
GPa, which is at the limit of known conducting materials with conductivity
higher than 70% International Annealed Copper Standard and sizes suitable
for building high field magnets. The design of high field magnets is limited
by these forces and, consequently, by the available materials. At the same
time, the materials need to have excellent physical properties. For
instance, the conductors need to have high electrical conductivity and high
specific heat and the superconductors should have high critical current in
field and low alternative current losses. This paper outlines our
requirements and research on metal matrix composite materials for building
high field magnets. The discussions include both the macrocomposite and
microcomposite. The scales of the structures in the composites are from
millimeters to nanometers.