Citation

Heshmati-Manesh S. Iranian Journal of Science and Technology, Transaction B: Technology 1999; 23(3): 275-276.

Copyright

(Copyright © 1999)

DOI

unavailable

PMID

unavailable

Abstract

The microstructures of γ-TiAl alloys containing small amounts of Si were studied after hot forging and further annealing to investigate microstructural evolution. Important parameters such as forging temperature, forging ratio, annealing temperature and sequence of thermomechanical treatments were systematically studied. Isothermal forging below the α→α2+γ eutectoid temperature resulted in inhomogeneous dynamic recrystallization, and fine equiaxed grains were produced in recrystallized areas and residual α2+γ lamellae elsewhere. The eutectic suicides play an important role in destruction of the as-cast structure during the deformation and recrystallization. Also, the presence of fine suicides produced by precipitation in the solid state restricts the size of grains produced by dynamic recrystallization as well as by static recrystallization on subsequent annealing. © Shiraz University.

Language: en

Keywords

Grain refinement; Heat treatment; Hot deformation; hot forming; Microstructure; Nucleation; Precipitation; Recrystallization; Silicide; Thermomechanical treatment; Titanium-aluminide