Temperature Dependence of the Fracture Strength of Composite Corundum Materials Reinforced with Ni and NiAl Particles

摘要

The mechanical properties (fracture strength and Vickers microhardness HV) of corundum-based composite materials containing disperse Ni and NiAl particles are studied. The material samples are prepared by sintering in vacuum at 1500℃ or through hot compaction at a temperature ranging from 1470 to 1570℃. The fracture strength of the samples based on Al_2O_3-Ni (2.2 vol %) and prepared through hot compaction at 1570℃ varies from 3.4 to 5.4 MPa m~(1/2) at 20℃ as the NiAl content varies from 5 to 40 vol %, respectively. When the Ni content is increased to 6.5 vol %, the fracture strength values vary from 3.1 MPa m~(1/2) (5 vol % of NiAl) to 5.1 MPa m~(1/2) (40 vol % of NiAl). The maximum fracture strength for the Al_2O_3-Ni (6.5 vol %)-NiAl (40 vol %) samples is 7.36 MPa m~(1/2) at 500℃.