ATI Titan 27™ - α+β Alloy with Superior Strength and Ductility

ATI Titan 27™ is an α+β alloy with superior strength, high-cycle fatigue, and workability compared to the legacy workhorse alloy Ti-6Al-4V. This alloy has a wider hot working range and can be produced in a variety of product forms: bar, billet, hot-rolled plate, and cold-rollable sheet. Similar microstructures to that of Ti-6Al-4V are observed via scanning electron microscopy (SEM) when imaged in the backscatter electron (BSE) imaging mode, with ATI Titan 27™ having a slightly higher phase fraction (20%) of the body-centered cubic (BCC) β phase. The strength of ATI Titan 27™, as determined by room temperature tensile tests, was measured to be 15% greater than that of Ti-6Al-4V. Electron backscatter diffraction (EBSD) was performed on as-deformed specimens to characterize the overall slip behavior. Additionally, less room-temperature load drop during stress relaxations tests indicate the potential of this alloy as a replacement for Ti-6Al-4V in applications sensitive to dwell-fatigue. The novel strength and ductility of ATI Titan 27™, with increased slip activation of non-close packed planes, could enable future light weighting and improved dwell fatigue resistance.