Hardening behavior of Pt–Ti microalloys

• Microalloying Pt with Ti improves solid solution strengthening and process hardening.
• Work hardening of aged microalloys was not obvious between 20% and 70% deformation.
• Our Pt–Ti microalloy exhibited no significant age hardening behavior.
• Work hardening of aged alloys is better than that of quenched alloys.
• Pt–Ti microalloy hardness after recrystallization is >2.6 times that of annealed Pt.

Microalloys of platinum containing 0.3 or 0.5 wt% titanium (Pt–0.3Ti and Pt–0.5Ti, respectively) were studied to determine their solid solution hardening, age hardening, work hardening, and annealing softening behavior. The obtained results revealed that the solid solution hardening and work hardening effects are both quite significant. The quenching hardness (114 HV), processing hardness (202 HV with 90% rolling), and annealing hardness (130 HV after 1 h at 800 °C) of the Pt–0.5Ti microalloy are 1.7, 2.0, and 2.6 times greater, respectively, than that of pure Pt. The work hardening curves of the aged microalloys were also unique in that a deformation of 20–70% produced no discernible work hardening of the microalloys.