Strengthening of Ti-6A1-4V alloy by induction heat treatment

Abstract

This study was conducted to clarify the effect that quenching after induction heating for a short time (60 s) has on the mechanical properties and fatigue strength of Ti-6A1-4V alloy which is one of the most typical α + β titanium alloys. When heating temperature was higher than 1 173 K, the above heat treatment induced the transformation from β-phase to ά martensite possessing a high hardness. Such creation of ά-phase greatly improved both the tensile strength and fatigue strength of the alloy although it decreased the ductility. However, in case that heating temperature was higher than β- transus temperature (1 268 K), the improvement of the tensile strength and fatigue strength was limited by growth of previous β-grains. The above results showed that the appropriate temperature of the induction heat treatment for strengthening of Ti-6Al-4V alloy is between 1 173 K and β- transus temperature when heating time is 60 s.