Recent advances in strengthening titanium alloys through alloying elements

Abstract Operating temperature beyond 600 °C reduces fatigue strength, fracture toughness, wear resistance, corrosion resistance, oxidation resistance, surface hardness, modulus of elasticity, and strength of Ti alloys. These limitations restrict their high-strength, high-temperature applications in different industries, thus enhancing their properties. This paper critically reviews past research on different aspects of the properties enhancement of Ti alloys, describing transformations of their phases and their morphologies, as well as different phase stabilizing elements for Ti alloys. Various chemical, mechanical, and physical surface modification techniques used to enhance the properties of these alloys are discussed, highlighting their major limitations. Adding different elements to Ti alloys is highlighted as a simple and efficient technique to enhance their properties significantly. The contributions of different elements added to Ti alloys to enhance their properties and high-temperature performance are examined. This paper explains different methods used to add different elements to Ti alloys and elaborates on the mechanisms by which addition of these elements refines the grains and improves mechanical properties and high-temperature performance of Ti alloys. Design methodologies for Ti alloys are also presented. The capabilities of additive manufacturing processes used to fabricate Ti alloy components and tailored properties are also highlighted. Some typical applications of properties enhanced Ti alloys in aerospace, space, biomedical, marine and ship building, chemical, and automotive industries are also mentioned. Finally, directions for future research are suggested. This review paper will be very useful in designing and developing Ti alloys with enhanced properties through the selection of appropriate elements.