Abstract
The continuous cooling transformation diagrams of titanium-base alloys of allotropic transformation type have been reported by the present authors in the previous paper. In this paper are summarized the continuous cooling transformation diagrams of titanium alloys of eutectoidal type, such as Ti-Fe, Ti-Mn, Ti-Cr, Ti-Co and Ti-Bi.
The specimens were soaked at a temperature of β phase prior to quenching. Quenching was carried out by argon gas jet stream. During quenching, cooling curve was recorded by an electromagnetic oscillograph. Starting point and finishing point of β→α transformation, Ms point and Mf point have been determined from the cooling curves. From these measurements, the continuous cooling transformation diagram was constructed for the respective alloys.
The velocity of β→α transformation of titanium alloys tested decreases, in general, by the addition of an alloying element and the Ms temperature for the formation of α′ phase is almost linearly dependent on the content of alloying element. Dominant stabilization effects are operative above 5%Fe.
