抄録
In this study, the effect of Al content on isochronal heat treatment behavior in Ti-13Cr-1.2Fe-Al alloys was investigated by measurements of electrical resistivity and Vickers hardness, X-ray diffraction and transmission electron microscope observation. The results obtained are as follows.
In the solution treated and quenched state (STQ), resistivity (ρ) at liquid nitrogen (LN) and room temperatures (RT) increased monotonously with Al content. 0%Al and 3.0%Al alloys consisted of retained β phase and athermal ω.
In the isochronal heat treatment, two minima of resistivity were observed at 623 K and 823 K. The former is due to the precipitation of isothermal ω phase and the latter is α precipitation. The temperature of resistivity minimum attributing to ω phase precipitation gradually increases with increasing of Al content. In 4.5%Al and more, the minimum of resistivity by ω precipitation disappears and the minimum caused by α precipitation remained. It is considered that Al content above 4.5% was suppressed ω precipitation and enhanced α precipitation.
