PREPARATION OF FUNCTIONALY GRADED MATERIALS USING THE MECHANICALY ALLOYED METALIC-POWDER AND ITS MECHANICAL PROPERTIES

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Titanium and boron powders were mixed various contents of molar ratio Ti/B=1/2 to copper and aluminum powders and the mixture was mechanically alloyed for various milling periods. The copper and aluminum matrix phases super-saturated with are formed and the ciystalline size of matrix phases became to nanometer order.Microstructural changes in the alloy powder with the age treatment were investigated by small-angle scatter technique in the X-ray diffraction. In an early stage of the age treatment for the mechanically alloyed Cu-Ti-B powder forms a modulated structure. After the age treatment for long time, titanium boride phases such as TiB_2, TI_2 B_5 and Ti_3 B_4 form in the mechanically alloyed Cu-Ti-B and AL-TI-B alloy powders.Consolidation of the lamellar compact as functionally material was estimated from standpoints of densification and mechanical strength of the compact and microsti-ructural change in the each alloy layer during vacuum hot pressing. The lamellar compact is homogeneously densely formed without curved contours by the vacuum hot pressing for shorter treating time at lower temperature than conventional sintering after cold compacting. The lameller compact hot-pressed in the vacuum atmosphere has high rupture strength in the bending.