POWDER-METALLURGY PROCESSING OF NB-TIO2 MATERIALS

Nb-xw/oTiO(2)(0.5 less than or equal to x less than or equal to 1.0) a lloys strengthened by an oxide dispersion (ODS), exhibit properties th at make them potential materials for surgical implants. These alloys h ave been processed by a powder metallurgy technique. Compaction and si ntering tests were carried out in order to understand microstructural evolution in these materials during processing. Phenomena such as the dissolution of TiO2 particles and oxygen degassing due to volatilizati on of niobium suboxides take place during sintering in a high vacuum. Results suggest that additions of TiO2 up to 1w/o cause a slight incre ase in the sinterability of niobium below 1400 degrees C. An explanati on for the role of TiO2 particles during sintering is proposed.