Ti-Al及びTi-Al基合金の高温における諸性質について

抄録

At the temperature range between 500° and 800°, the hardness, the resistance to deformation and the oxidation behavior of some kinds of Ti-Al-base alloys have been stadied. The nominal compositions of the alloys tested were Ti-1%Al, Ti-3%Al, Ti-5%Al, Ti-5%Al-2%Cu, Ti-5%Al-0.5%Si and Ti-5%Al-2.5%Sn. The results obtained may be summarised as follows: (1) The addition of aluminium increases the hardness and the resistance to deformation of titanium. (2) The addition of the third elements to Ti-5%Al increases the resistance to deformation conspicuously at the temperature range 700∼800°. (3) Aluminium improves the oxidation resistance of titanium and prevents the diffusion of oxygen to the metallic core. (4) Generally, the ternary alloys showed excellent oxidation resistance compared with that of binary alloys. (5) Many knick points, that is the abrupt change of reaction velocity of oxidation, have been observed on the oxidation-time curves at 800°. (6) According to the results of electron-diffraction analysis,the scales formed by the oxidation were found always consisting of rutile(TiO₂).