Method of making a boron nitride protection against melt- through of an arrangement placed underneath a nuclear reactor hearth

摘要

A protection 1, 5 against melt-through of an arrangement 3, 7 placed underneath a nuclear reactor hearth, in which molten material can be accommodated upon melting of the hearth in a nuclear reactor, is produced by isostatic pressing of hexagonal boron nitride at a temperature of at least 1600 degrees Celsius and a pressure of at least 50 MPa. The protection can be enclosed in a shell 2, 6 of steel or other metal plates.