Effect of the Metallic Aging on the Microstructure and Mechanical Properties of Titanium Alloy

MRS Advances ◽  
2017 ◽  
Vol 2 (50) ◽  
pp. 2837-2845
Author(s):  
T.J. Sánchez-Rosas ◽  
J.D. Muñoz-Andrade ◽  
M. Aguilar-Sánchez ◽  
B. Vargas-Arista ◽  
E. Garfias-García

ABSTRACTDifferent aging heat treatments were performed in a Titanium alloy using as aging media metallic baths in comparison to typical furnace aging. As a first step, a Duplex Aging (DA) consisted of solubilization followed by quenching to room temperature after aging heat treatment in different metallic baths (Zn, Sn and Bi). A second procedure was Alternative Aging (AA) which consisted of solubilization and direct aging inside three different aforementioned baths. Microstructural aging variations begins at half hour until 30 h at 550°C inside metallic bath of Zn, Sn or Bi. Both kinds of aging promoted a microstructural variation and so on microhardness values. Microstructural analysis by Optical Microscopy showed a structural refinement after AA treatment. The highest hardness value of 375 HVN was achieved in Alternative Aging with Zn bath, which was found to be dependent on laminar α phase refining. Moreover, after AA treatment for 0.5, 1, 2, 3, 4, 10 and 30 h at 550°C in the metallic bath of Zn and Sn, the results indicated similar hardness values in different times, resulting in the fastest kinetic for Sn metallic bath at 2 h compared to that 4 h in Zn metallic bath. The observed increase in micro-hardness is not very attractive, it is recommended to use large aging times in order to stabilize final spacing of microstructural features in AA treatment.

2010 ◽  
Vol 97-101 ◽  
pp. 153-157
Author(s):  
Tao Wang ◽  
Hong Zhen Guo ◽  
Jian Hua Zhang ◽  
Ze Kun Yao

The microstructures and room temperature and 600°C tensile properties of Ti-5.8Al-4.0Sn-4.0Zr-0.7Nb -0.4Si-1.5Ta alloy after isothermal forging have been studied. The forging temperature range was from 850°C to 1075°C, and the constant strain rate of 8×10-3/S-1 was adopted. With the increase of forging temperature, the volume fraction of primary α phase decreased and the lamellar α phase became thicker when the temperatures were in range of 850°C -1040°C; The grain size became uneven and the α phase had different forms when the forging temperature was 1040°C and 1075°C respectively; The tensile strength was not sensitive to the temperature and the most difference was within 20MPa. Tensile strength and yield strength attained to the maximum when temperature was 1020°C; the ductility decreased with the increase of forging temperature, and this trend became more obvious if forging temperature was above the β-transus temperature.


2021 ◽  
Vol 1035 ◽  
pp. 89-95
Author(s):  
Chao Tan ◽  
Zi Yong Chen ◽  
Zhi Lei Xiang ◽  
Xiao Zhao Ma ◽  
Zi An Yang

A new type of Ti-Al-Sn-Zr-Mo-Si series high temperature titanium alloy was prepared by a water-cooled copper crucible vacuum induction melting method, and its phase transition point was determined by differential thermal analysis to be Tβ = 1017 °C. The influences of solution temperature on the microstructures and mechanical properties of the as-forged high temperature titanium alloy were studied. XRD results illustrated that the phase composition of the alloy after different heat treatments was mainly α phase and β phase. The microstructures showed that with the increase of the solution temperature, the content of the primary α phase gradually reduced, the β transformation structure increased by degrees, then, the number and size of secondary α phase increased obviously. The tensile results at room temperature (RT) illustrated that as the solution temperature increased, the strength of the alloy gradually increased, and the plasticity decreased slightly. The results of tensile test at 650 °C illustrated that the strength of the alloy enhanced with the increase of solution temperature, the plasticity decreased first and then increased, when the solution temperature increased to 1000 °C, the alloy had the best comprehensive mechanical properties, the tensile strength reached 714.01 MPa and the elongation was 8.48 %. Based on the room temperature and high temperature properties of the alloy, the best heat treatment process is finally determined as: 1000 °C/1 h/AC+650 °C/6 h/AC.


Metals ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 576 ◽  
Author(s):  
Bin Yan ◽  
Hongbo Li ◽  
Jie Zhang ◽  
Ning Kong

In this study, the effect of initial annealing microstructure of Ti–4Al–2V (TA17) alloy on forming characteristic was studied, so as to provide a basis for quality control of plastic forming of titanium alloy parts. The titanium alloy always undergoes annealing treatment before forming, due to different microstructures present different mechanical properties. The TA17 with different microstructures are obtained by means of various annealing treatment temperatures. The tensile behavior of TA17 is investigated at room temperature and 900 °C under constant strain rate of 0.01 s−1. The experimental results show that the mechanical properties of TA17 are sensitive to the initial microstructure before deformation. The microstructure of TA17 at 850 °C (2 h) is the equiaxed primary α-phase after the annealing process. It exhibits good plasticity at room temperature. This phenomenon is also confirmed from fracture morphology from the scanning electron microscope (SEM) analysis. At 900 °C, which is a high tensile temperature, the alloy with equiaxed primary α-phase performs outstanding plasticity compared with other microstructures. This work establishes a good understanding on the relationship between the mechanical properties and microstructures of TA17 at a wide temperature range.


Materials ◽  
2019 ◽  
Vol 12 (24) ◽  
pp. 4065
Author(s):  
Bingfeng Wang ◽  
Xu Ding ◽  
Ying Mao ◽  
Lanyi Liu ◽  
Xiaoyong Zhang

Shear localization is the main deformation mode for the near beta titanium alloy Ti-5Al-5Mo-5V-1Cr-1Fe loaded at high strain rates at either room temperature or cryogenic temperature. Nanoindentation, transmission electron microscopy, and high-resolution electron microscopy technique are applied to character the microstructure features and mechanical properties in the shear band of near beta titanium alloy. A white and straight band is observed in the shear region. Both microhardness and nanoindentaion hardness in the shear region are inferior to those in matrix. The different microstructure in the edge and the center in the shear band contribute to different mechanical properties. The plasticity of the entire shear band is almost homogenous when specimens are deformed at the cryogenic temperature. Rotational dynamic recrystallization is responsible for the formation of the ultrafine grains in the shear band. The edge of the shear band is composed of elongated grains, while there are ultrafine equiaxed grains in the center of the shear band. Deformation temperature has significant influence on the process of the grain refinement and the phase transformation in the shear band (SB). The grain sizes of the shear band in the specimen deformed at room temperature are larger than those in the specimens deformed at cryogenic temperature. The shear band consists of α phase grains in the specimen deformed at room temperature, and the shear band consists of α phase and lath-like α′ phase grains in the specimen deformed at cryogenic temperature. Finally, the mechanisms for phase transformation in the shear band are illustrated.


2016 ◽  
Vol 258 ◽  
pp. 550-553
Author(s):  
Héloise Vigié ◽  
Aurélie Soula ◽  
Bernard Viguier

Ti-β21S is a β-metastable titanium alloy, currently used in industries such as aeronautics, because of its cold formability, good mechanical properties at elevated temperature, low density and its strong resistance to oxidation. This alloy is hardened by an α-phase precipitation in the β-matrix. The purpose of the present research is to establish the effect of aging on the microstructure and mechanical properties of Ti-β21S. Different thermal aging tests have been carried out at 600°C and at 650°C for 500 hours in laboratory air. The evolution of the microstructure has been reported after each thermal treatment and associated with room temperature tensile tests results.


2020 ◽  
Vol 44 ◽  
pp. 24-30 ◽  
Author(s):  
Ruifeng Dong ◽  
Jinshan Li ◽  
Hongchao Kou ◽  
Jiangkun Fan ◽  
Yuhong Zhao ◽  
...  

1988 ◽  
Vol 133 ◽  
Author(s):  
K. S. Kumar ◽  
S. K. Mannan

ABSTRACTThe mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.


Materials ◽  
2021 ◽  
Vol 14 (8) ◽  
pp. 2021
Author(s):  
Oleksandr Lypchanskyi ◽  
Tomasz Śleboda ◽  
Aneta Łukaszek-Sołek ◽  
Krystian Zyguła ◽  
Marek Wojtaszek

The flow behavior of metastable β titanium alloy was investigated basing on isothermal hot compression tests performed on Gleeble 3800 thermomechanical simulator at near and above β transus temperatures. The flow stress curves were obtained for deformation temperature range of 800–1100 °C and strain rate range of 0.01–100 s−1. The strain compensated constitutive model was developed using the Arrhenius-type equation. The high correlation coefficient (R) as well as low average absolute relative error (AARE) between the experimental and the calculated data confirmed a high accuracy of the developed model. The dynamic material modeling in combination with the Prasad stability criterion made it possible to generate processing maps for the investigated processing temperature, strain and strain rate ranges. The high material flow stability under investigated deformation conditions was revealed. The microstructural analysis provided additional information regarding the flow behavior and predominant deformation mechanism. It was found that dynamic recovery (DRV) was the main mechanism operating during the deformation of the investigated β titanium alloy.


Vacuum ◽  
2021 ◽  
Vol 189 ◽  
pp. 110272
Author(s):  
Libo Zhou ◽  
Jinshan Sun ◽  
Ruizhi Zhang ◽  
Jian Chen ◽  
Jianjun He ◽  
...  

2007 ◽  
Vol 26-28 ◽  
pp. 367-371
Author(s):  
Hong Zhen Guo ◽  
Zhang Long Zhao ◽  
Bin Wang ◽  
Ze Kun Yao ◽  
Ying Ying Liu

In this paper the effect of isothermal forging process parameters on the microstructure and the mechanical properties of TA15 titanium alloy was researched. The results of the tests indicate that, in the range of temperature of 850 °C~980 °C and deformation degree of 20%~60%, with the increase of temperature or deformation, as the reinforcement of deformation recrystallization, the primary α-phase tends to the spherical shape and secondary α-phase transforms from the acicular shape to fine and spherical shape with disperse distribution, which enhance the tensile properties at room and high temperature. With the increment of forging times, the spheroidization of primary α-phase aggrandizes and secondary α-phase transforms from spherical and acicular shape to wide strip shape, which decrease the tensile properties at room and high temperature. The preferable isothermal forging process parameters are temperature of 980 °C, deformation degree of 60%, and few forging times.


Sign in / Sign up

Export Citation Format

Share Document