  This paper gives a review of studies of superconductors with a porosity above
50%. The pores in such superconducting materials provide refrigerant
penetration, efficient heat dissipation and stable operation. Methods for the
synthesis of the main groups of porous superconductors are described. The
results of studies of the structural, magnetic, and electrical transport
properties are presented, and the features of the current flow through porous
superconductors of various types are considered.
