INVESTIGATION OF THE FORMATION OF TITANIUM ALUMINIDE TI3AL FROM A SOLID SOLUTION BY THE MODULUS OF ELASTICITY METHOD

The effect of heat treatment of Ti-Al alloys of constitution near to that of Ti3Al and contg. 15.9 and 16.6 percent Al by wt. on their mech. properties were studied. The modulus of elasticity E and the modulus of transverse elasticity G were detd. by the resonance method. The specimens were annealed at 600 degrees for 200 hrs., then were heated in sealed quartz ampuls at 800, 900, 1000, 1100, 1150, 1200, and 1300 degrees for 48, 24, 18, 3, 2, 1, and 0.4 hrs., resp., and quenched in water. The results obtained show the continuous decrease of E and G, as the quenching temps. increase in the range of 900-1100 degrees for 15.9 percent and 900-1150 degrees for 16.6 percent Al. Further increasing of these temps. caused increase of E and G. Afterwards the specimen of 15.9 percent Al was quenched from 1100 degrees again and the effect of the duration of its tempering at 600, 700, and 800 degrees on the parameters investigated was studied. G and E increase only during the 1st 5-10 hrs. of tempering at 600-700 degrees. Further holding of alloy at these temps. did not affect these parameters. The tempering at 800 degrees caused increase of G and E only during the 1st 2 hrs. and further holding caused decrease of these parameters down to values for as-quenched state.
Edited machine trans. of mono. Diffuzionnye Protsessy v Metallakh (Diffusion Processes in Metals), n.p., 1968 p110-113.