“…For instance, hot-pressed B 4 C-TiB 2 composite prepared by Ru showed high strength and toughness of 506 MPa and 9.4 MPa m 1/2 , respectively, but the hardness was just only 23.6 GPa [15]. In comparison, hot-pressed B 4 C-TiB 2 composite prepared by J.Vleugels showed a combination of high strength and high toughness of 867 MPa and 29 GPa, while the fracture toughness was modest (4.5 MPa m 1/2 ) [16]. Similar phenomenon was also observed by Yamada.…”