ZrC ceramics have good prospects for application in high-temperature and high-pressure environments,but their low toughness limits their practical applications.Zr-Al-C ternary layered compounds have good mechanical properties,so in this paper,single-phase dense Zr3Al3C5 ceramics were prepared by spark plasma sintering using Zr,Al and C powder as raw materials,and the reaction process and mechanical properties of Zr3Al3C5 compounds were investigated.The results showed that at 700 ℃,a large amount of Zr-Al intermetallic compounds were generated.At 900 ℃,the ZrAl3 compounds were transformed into Zr2Al3 and ZrAl2,and A14C3 and ZrC compounds were formed simultaneously.When the temperature reached 1300 ℃,the Zr3Al3C5 compounds appeared,but during the sintering process,Zr2Al3C4 compounds were generated due to the local inhomogeneity caused by the extremely easy melting of Al.When the temperature reached 1700 ℃,single-phase dense Zr3Al3C5 ceramics were prepared.The hardness and Young's modulus of Zr3Al3C5 ceramics reached 10.9 GPa and 310 GPa,respectively,and the fracture toughness was 3.8 MPa·m1/2±0.16 MPa·m1/2.The lamellar structure and elongated grain structure allowed the energy dissipation during fracture and improved the fracture toughness.
万方数据
