| 摘要 |
FIELD: plastic metal working; manufacture of blanks, semi-finished items and articles with specified structure. SUBSTANCE: method of treatment of cast hypereutectoid alloys on base of titanium aluminides gamma-TiAl and alpha2Tl3Al includes heating and deformation performed at two stages; at first stage, deformation of blank is performed at temperature of gamma-TiAl, where alpha2Ti3Al is eutectoid temperature; Te/Te+DeltaT°C is selected from condition of retaining globular component of structure obtained in the course of deformation, at cooling after deformation; rate of deformation Te - is selected in interval of DeltaT whose upper limit is limited by deformability of alloy and lower limit is limited by condition of prevailing of recrystallization/globularization processes as compared with return processes; degree of deformation epsilon'1 is so selected that medium size of grains/colonies in blank decreases to magnitudes causing reduction of friable- brittle transient temperature epsilon'lmin-epsilon'lmax of blank to ∈1 at temperature and rate of deformation selected within said intervals; at second stage, deformation is performed under isothermal conditions at temperature within T*, where T*<Te, is minimum temperature at which deformation takes place without rupture at degree of deformation of Tmin-T°eC and rate of deformation of Tmin which are selected on the condition of obtaining size ∈2 of grains and of particles due to recrystallization/globularization processes. Proposed method ensures obtaining of homogeneous finegrained structure at grain size gamma lesser than 5 mkm and size of alpha2 particles lesser than 1 mkm. EFFECT: enhanced efficiency. 20 cl, 10 dwg, 1 tbl, 5 ex |
