The Preparation Of Porous Nb-Ti And Its Infiltration With Aluminium

The porous Nb-Ti preform, in which the solid fraction is of 56.8%,59.2% and 61.6% respectively, was prepared by freeze drying process. The prepared Nb-Ti bodies with open pore structures have been infiltrated with aluminum melt at 1000℃, 1100℃,1200℃, which was conducted in a vacuum furnace, by pressureless infiltration technique. The morphologies, microstructure and phases existed in the metallic glass matrix composites have been analyzed and identified by scanning electron microscope (SEM), energy disperse spectroscopy (EDS), X-ray diffraction (XRD), and differential scanning calorimetry (DSC). The mechanical properties, such as hardness testing, compressive testing, have also been evaluated preliminarily at room temperature. The results indicate that the prepared composite materials is a kind of metallic glass matrix composites, which is composed of Al、Nb、Zr and Ti chemical elements. And the dendritic and the cellular solidified microstructures which can improve the plastic property of the composite were embedded into the metallic glass matrix. On the other hand, a regular honeycomb structures can be observed inside the metallic glass matrix composites macroscopicly, which indicates that the prepared metallic glass matrix composites may have some excellent properties corresponding to the specific honeycomb structures. The experimental results suggested that the prepared materials have some outstanding mechanical properties compared with pure aluminium, such as good elastic deformation, excellent ambient plasticity, and high compressive strength. The yield strength of the prepared metallic glass matrix composite which solid fraction is of 61.6% can reach to 157.089 MPa.