Effect of spatial distribution of TiC_p on tensile properties of sintered Ti/TiC_p composites

摘要

The composites of the different dispersion state were prepared from the titanium powder and the TiC with the different particle sizes. The effect of the difference of spatial distribution of the TiC particles on the tensile properties and the behavior of TiC particles' breaking in the tensile deformation process have been quantitatively investigated. In tensile deformation, TiC particles begin to break just after the yielding of the material. Finally the connection of cumulated cracks of particles brings the propagation of a main crack and fracture of the composite material. The material of which the spatial distribution of the second phase particles is close to random distribution has larger tensile strength and tensile ductility than the material of stronger clustering tendency. The reason for this is that the destruction of TiC particles in the materials of stronger clustering tendency is more frequent from the initial stage of the deformation, because they have more regions of larger local volume fraction and larger local particle density. The tendency, showing that the particles in the clustered regions are easy to be broken, was explained from the result of the elastic-plastic analysis by finite element method.