THE HEAT TREATMENT OF TI-3AL-8V-CR-4MO-4ZR TITANIUM ALLOY MATERIALS

摘要

In the present invention, high durability (fatigue limit / tensile strength) by improving the fatigue strength of the titanium alloy of β-C type Ti-3Al-8V-6Cr-4Mo-4Zr, which is expected to be applied to high-performance driving parts due to excellent cold workability. ), A heat treatment method was obtained.;In the case of general steel, fatigue limit (fatigue strength) increases or decreases in proportion to mechanical strength such as tensile strength and hardness, but in the present Ti-3Al-8V-6Cr-4Mo-4Zr titanium alloy, The phenomenon is not applied.;Therefore, in the present invention, unlike the heat treatment conditions generally recommended by the manufacturer or the existing engineering data for Ti-3Al-8V-6Cr-4Mo-4Zr titanium alloy, 700 ℃ (675 ~ 725 ℃) much lower than the transformation point 793 ℃ Solution is maintained by air cooling after 30 ~ 60 minutes in the air), and the heat treatment method of aging treatment by air cooling after 10 ~ 20 hours at 510 ~ 550 ℃ is used to maximize the fatigue limit. (Fatigue limit / tensile strength) Improved to about 0.589.