Several diborides, carbides and nitrides of the group IVB and VB transition metals are a family of materials known as ultrahigh temperature ceramics based on melting temperatures in excess of 3000`C. In recent years, hafnium and zirconium borides in Это и многое другое вы найдете в книге ZrB2 and ZrB2–based ceramics (Xinghong Zhang,Jiecai Han and Zhi Wang)