METHOD FOR MAKING SEMIFINISHED PRODUCTS OF TITANIUM ALLOYS WITH INTERMETALLIDE STRENGTHENING Russian patent published in 2002 - IPC

FIELD: powder metallurgy, namely, manufacture of semifinished products of titanium alloys alloyed with elements forming intermetallide compounds with titanium such as silicone, carbon, boron, rare-earth metals. SUBSTANCE: method comprises steps of making powder of melt by cooling; making blank by hot isostatic pressing; hot deformation of blank; heat treatment of it. Before hot isostatic pressing powder is degassed due to soaking it in vacuum at residual pressure no more than 1 Pa for 1-2 h at 20 C and then it is heated up to temperature of 150-180 C and soaked for 0.5-2.5 h at pressure no more 1 Pa. Hot deformation of blank is performed at temperature lower than that of polymorphic conversion by temperature 10-70 C at deforming rate 0.01-0.8 m/s by one or several passes at total forging reduction 3-30. Heat treatment is realized by three stages: at first stage temperature is raised from 20 C up to (870-920)C and maintained for 2-5 h; at second stage temperature is reduced until 790-830 C and maintained for 2-5 h, then blank is cooled until 20 C; at third stage temperature is raised from 20 C until 570-650 C and maintained for 6-10 h, then blank is cooled until 20 C. EFFECT: enhanced mechanical properties, operational characteristics of semifinished products with lowered oxygen content. 2 cl, 1 tbl