Metastability in co-Tiintermetallic Compounds Sintered by SPS.

Extract

The mechanical alloying (MA) process is an effective method to develop strategic materials with novel structures. These can be solid solutions (even in immisible systems), amorphous phases, fine particle sized and nano-metric crystals etc. Conventional powders metallurgy routes can process the mechanical alloyed products. However, the novel features conferred into the powders, can be lost during the sintering operations. The spark plasma sintering process (SPS) is an alternative route to dense mechanically alloyed products at a high grade while retaining their novel structures. Co-Ti alloys were produced by mechanical alloying the elemental powders mixtures with nominal composition Co₅₀Ti₅₀ (at. %). Details on the preparation and characterisation of the milled products can be found in related publications. Densification of the powders products was conducted using a Dr. Sinter equipment. Previous studies on Co-Ti alloys processed by MA and SPS have shown that the final products are composed of mixtures of metastable intermetallic compounds.