TITLE:
Influence of Plastic Deformation and Aging Process on Microstructure and Tensile Properties of Cast Ti-6Al-2Sn-2Zr-2Mo-1.5Cr-2Nb-0.1Si Alloy
AUTHORS:
Mostafa S. S. El-Deeb, Khaled M. Ibrahim, S. S. Mohamed, Ramadan N. Elshaer
KEYWORDS:
TC21 Ti-Alloy, Strain Hardening, Microstructure, Aging, Hardness, Tensile
JOURNAL NAME:
Open Journal of Metal,
Vol.11 No.2,
June
17,
2021
ABSTRACT: In the present work, titanium alloy with a composition of
Ti-6.5Al-3Mo-1.9Nb-2.2Sn-2.2Zr-1.5Cr (TC21) was subjected to plastic deformation and aging processes. A Plastic deformation at room temperature with 2%, 3% and 4% stroke strain was applied on the studied samples. Then, the samples aged at 575°C for 4 hr. By applying different plastic deformation ratios, the structure revealed an elongated and thin β-phase embedded in an α-phase. Secondary α-platelets were precipitated in the residual β-phase. Maximum hardness (HV440) was obtained for 4% deformed + aged samples. Minimum hardness (HV320) was recorded for the as-cast samples without deformation. The highest ultimate tensile strength of 1311 MPa was obtained for 4% deformed + aged samples due to presence of high amount of dislocation density as well as precipitation of secondary α-platelets in the residual β-phase. The lowest ultimate tensile strength of 1020 MPa was reported for as-cast samples. Maximum elongation of 14% was registered for 4% deformed + aged samples and minimum one of 3% was obtained for as-cast samples. Hence, strain hardening + aging can enhance considerably the elongation of TC21 Ti-alloy up to 366% and 133% in case of applying 4% deformation + aged compared to as-cast and aged samples without applying plastic deformation, respectively.