“…respectively, of TaB 2 • NbB 2 • TiB 2 , and ZrB 2 . The results we have obtained on the composition of the boride layers on tungsten and molybdenum are in good agreement with the data in [25,30], and on tantalum, niobium, titanium, and zirconium, with the data in [24]. Figure 17 shows typical microstructures of boride layers on the investigated metals.…”