Development and heat treatment of β-phase titanium alloy for orthopedic application

The effects of near β heat treatment on the microstructure of TC18 alloy during three temperature stages were studied. The results show that the microstructure of the sample is tri-modal microstructure after near β heat treatment, and the size of αp does not significantly, but dispersible αs increases and has a tendency to merge, and then it would not grow up anymore ; β phase would grow up, but the grain boundary has some broken. The experiment result shows that the tri-modal microstructure could obtain high damage tolerance properties of titanium alloy in theory.

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The Heat Treatment Influence on the Microstructure and Hardness of TC4 Titanium Alloy Manufactured via Selective Laser Melting

Materials ◽

10.3390/ma11081318 ◽

2018 ◽

Vol 11 (8) ◽

pp. 1318 ◽

Cited By ~ 19

Author(s):

Zhan-Yong Zhao ◽

Liang Li ◽

Pei-Kang Bai ◽

Yang Jin ◽

Li-Yun Wu ◽

...

Keyword(s):

Heat Treatment ◽

Titanium Alloy ◽

Critical Temperature ◽

Selective Laser Melting ◽

Heat Treatment Temperature ◽

Treatment Temperature ◽

Laser Melting ◽

Β Phase ◽

Α Phase ◽

Increasing Temperature

In this research, the effect of several heat treatments on the microstructure and microhardness of TC4 (Ti6Al4V) titanium alloy processed by selective laser melting (SLM) is studied. The results showed that the original acicular martensite α′-phase in the TC4 alloy formed by SLM is converted into a lamellar mixture of α + β for heat treatment temperatures below the critical temperature (T0 at approximately 893 °C). With the increase of heat treatment temperature, the size of the lamellar mixture structure inside of the TC4 part gradually grows. When the heat treatment temperature is above T0, because the cooling rate is relatively steep, the β-phase recrystallization transforms into a compact secondary α-phase, and a basketweave structure can be found because the primary α-phase develop and connect or cross each other with different orientations. The residence time for TC4 SLM parts when the treatment temperature is below the critical temperature has little influence: both the α-phase and the β-phase will tend to coarsen but hinder each other, thereby limiting grain growth. The microhardness gradually decreases with increasing temperature when the TC4 SLM part is treated below the critical temperature. Conversely, the microhardness increases significantly with increasing temperature when the TC4 SLM part is treated above the critical temperature.

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Effect of Heat Treatment on the Microstructure and Dynamic Behavior of Ti-10V-2Fe-3Al Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.910.155 ◽

2018 ◽

Vol 910 ◽

pp. 155-160 ◽

Cited By ~ 2

Author(s):

An Jin Liu ◽

Lin Wang ◽

Hua Xiang Dai

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Titanium Alloy ◽

Yield Strength ◽

Dynamic Compression ◽

Aging Treatment ◽

Solution Temperature ◽

Β Phase ◽

Solution Treated ◽

Α Phase

Microstructure evolution and compression property of Ti-10V-2Fe-3Al titanium alloy were studied in this paper. Solution treatments were performed at temperature ranging from 710°C to 830°C and some followed by aging treatment. Ti-10V-2Fe-3Al alloys with α+β phase show higher mechanical properties compared with single β phase alloy. With the increase of solution temperature, the content of equiaxed α phase decrease. Consequently, the strength of the alloy increases while the plasticity drops down. The highest yield strength value of 1668 MPa was obtained in the sample treated by 770°C solution treated for 2 hours then water quenched and followed by 520°C aging for 8 hours then air cooled. The stress induced martensite α'' phase appeared after SHPB dynamic compression in the sample solution treated at 830°C.

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Effect of Heat Treatment on the Microstructure Evolution of Ti-6Al-3Sn-3Zr-3Mo-3Nb-1W-0.2Si Titanium Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.1828 ◽

2016 ◽

Vol 879 ◽

pp. 1828-1833 ◽

Cited By ~ 2

Author(s):

Xiao Yun Song ◽

Wen Jing Zhang ◽

Teng Ma ◽

Wen Jun Ye ◽

Song Xiao Hui

Keyword(s):

Heat Treatment ◽

Titanium Alloy ◽

Microstructure Evolution ◽

Solution Treatment ◽

Treatment Temperature ◽

Water Quenching ◽

Air Cooling ◽

Two Phase ◽

Β Phase ◽

Α Phase

Ti-6Al-3Sn-3Zr-3Mo-3Nb-1W-0.2Si (BTi-6431S) alloy is a novel two-phase high temperature titanium alloy for short-term using in aerospace industry up to 700°C. The effects of heat treatment on the microstructure evolution of BTi-6431S alloy bar were investigated through optical microscopy (OM), X-ray diffraction (XRD), electron probe microanalysis (EPMA) and transmission electron microscopy (TEM). The results show that solution treatment in β region at 1010°C followed by water quenching results in the formation of orthorhombic martensite α′′ phase, while air cooling leads to the formation of hexagonal martensite α′ phase. When solution-treated in α+β phase field at temperatures from 900°C to 980°C following by water quenching, the content of primary α phase decreases with the increase of heat treatment temperature. For the alloy subjected to identical heat treatment, the content of Al in α phase is much higher than that in β phase, while the contents of Nb, Mo and W elements in α phase are much less than those in β phase.

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Effect of Heat Treatment on Microstructure and Properties of Ti-6.5Al-1.5Mo-2.5V-2Zr Titanium Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.1076 ◽

2013 ◽

Vol 652-654 ◽

pp. 1076-1079

Author(s):

Bing Zhou ◽

Shang Zhou Zhang

Keyword(s):

Heat Treatment ◽

Titanium Alloy ◽

Phase Field ◽

Annealing Temperature ◽

Microstructure And Properties ◽

Β Phase ◽

Heat Treated ◽

Alloy Heat ◽

Relationship Of ◽

The Relationship

The relationship of microstructure and properties of Ti-6.5Al-1.5Mo-2.5V-2Zr titanium alloy heat-treated in the α+β phase field was studied. It was found that globular or bimodal microstructures were obtained for alloy annealed at 400-950°C. Ductility decreased with increasing annealing temperature, while the strength showed a minimum at 800°C. The properties at the center of billet are lower than that at the edge due to the low cooling rate after forging. With the increase of test temperature, the strength decreased and ductility increased.

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The Influence of Heat Treatment Temperature on Microstructures and Mechanical Properties of Titanium Alloy Fabricated by Laser Melting Deposition

Materials ◽

10.3390/ma13184087 ◽

2020 ◽

Vol 13 (18) ◽

pp. 4087 ◽

Cited By ~ 1

Author(s):

Wei Wang ◽

Xiaowen Xu ◽

Ruixin Ma ◽

Guojian Xu ◽

Weijun Liu ◽

...

Keyword(s):

Heat Treatment ◽

Titanium Alloy ◽

Testing Machine ◽

Optical Microscope ◽

Treatment Temperature ◽

Air Cooling ◽

Laser Melting ◽

Tc4 Titanium Alloy ◽

Β Phase ◽

Laser Melting Deposition

Ti-6Al-4V (TC4) titanium alloy parts were successfully fabricated by laser melting deposition (LMD) technology in this study. Proper normalizing temperatures were presented in detailed for bulk LMD specimens. Optical microscope, scanning electron microscopy, X-ray diffraction, and electronic universal testing machine were used to characterize the microstructures, phase compositions, the tensile properties and hardness of the TC4 alloy parts treated using different normalizing temperature. The experimental results showed that the as-fabricated LMD specimens’ microstructures mainly consisted of α-Ti phase with a small amount of β-Ti phase. After normalizing treatment, in the area of α-Ti phase, the recrystallized length and width of α-Ti phase both increased. When normalizing in the (α + β) phase field, the elongated primary α-Ti phase in the as-deposited state was truncated due to the precipitation of β-Ti phase and became a short rod-like primary α-Ti phase. In as-fabricated microstructure, the β-Ti phase was precipitated between different short rod-shaped α-Ti phases distributed as basketweave. After normalizing treatment at 990 for two hours with subsequent air cooling, the TC4 titanium alloy had significant different microstructures from original sample produced by LMD. The normalizing treatment methods and temperature can be qualified as a prospective heat treatment of titanium alloy fabricating by laser melting deposition.

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Recovery and Recrystallization Behavior of Large Sized β Phase Grains in TC18 Titanium Alloy during Annealing Process

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.263 ◽

2015 ◽

Vol 817 ◽

pp. 263-267

Author(s):

Meng Qi Yan ◽

Ai Xue Sha ◽

Wang Feng Zhang ◽

Yu Hui Wang

Keyword(s):

Heat Treatment ◽

Titanium Alloy ◽

Grain Growth ◽

Annealing Process ◽

Slow Cooling ◽

Center Layer ◽

Β Phase ◽

Complicated Process ◽

Minor Portion ◽

A Minor

The manufacturing processes of TC18 titanium alloy bar takes about 10 times forging. During forging, the β phase grain experiences a series complicated process such as recovery, recrystallization and grain growth. Larger sized β phase grains can easily be formed under different conditions such as insufficient deformation or slow cooling rate during the forging process, which may affect the mechanical properties of TC18 bars. In order to find out the causes and elimination methods of large β grains, this paper used EBSD techniques to analyze the microstructure and texture of TC18 titanium bar at center layer, 1/2R layer and surface layer after the process of forging and heat treatment. Results show that a large portion of β grains experiences recovery and grain growth, while a minor portion of β grains only experiences recrystallization after α+β region heat treatment. Most β grains experience recrystallization, while for those β grains which are hard to be swallowed by recrystallized grains only experience recovery after β region heat treatment. Rather than eliminate the large sized β grains, it’s even easier for those β grains to grow up during annealing process under the condition of insufficient deformation.

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Ti-5Al-4FeCr

Alloy Digest ◽

10.31399/asm.ad.ti0058 ◽

1969 ◽

Vol 18 (6) ◽

Keyword(s):

Heat Treatment ◽

Fracture Toughness ◽

Corrosion Resistance ◽

Titanium Alloy ◽

High Temperature ◽

Heat Treating ◽

Age Hardening ◽

Temperature Performance ◽

Alpha Beta ◽

Hardening Heat Treatment

Abstract Ti-5A1-4FeCr is an alpha-beta type titanium alloy recommended for airframe components. It responds to an age-hardening heat treatment. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: Ti-58. Producer or source: Titanium alloy mills.

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Dynamic Softening Mechanisms and Microstructure Evolution of TB18 Titanium Alloy during Uniaxial Hot Deformation

Metals ◽

10.3390/met11050789 ◽

2021 ◽

Vol 11 (5) ◽

pp. 789

Author(s):

Qiang Fu ◽

Wuhua Yuan ◽

Wei Xiang

Keyword(s):

Titanium Alloy ◽

Dynamic Recovery ◽

True Strain ◽

Hot Workability ◽

Compression Tests ◽

Phase Zone ◽

Β Phase ◽

Stability And Instability ◽

Dynamic Softening ◽

Transus Temperature

In this study, isothermal compression tests of TB18 titanium alloy were conducted using a Gleeble 3800 thermomechanical simulator for temperatures ranging from 650 to 880 °C and strain rates ranging from 0.001 to 10 s−1, with a constant height reduction of 60%, to investigate the dynamic softening mechanisms and hot workability of TB18 alloy. The results showed that the flow stress significantly decreased with an increasing deformation temperature and decreasing strain rate, which was affected by the competition between work hardening and dynamic softening. The hyperbolic sine Arrhenius-type constitutive equation was established, and the deformation activation energy was calculated to be 303.91 kJ·mol−1 in the (α + β) phase zone and 212.813 kJ·mol−1 in the β phase zone. The processing map constructed at a true strain of 0.9 exhibited stability and instability regions under the tested deformation conditions. The microstructure characteristics demonstrated that in the stability region, the dominant restoration and flow-softening mechanisms were the dynamic recovery of β phase and dynamic globularization of α grains below transus temperature, as well as the dynamic recovery and continuous dynamic recrystallization of β grains above transus temperature. In the instability region, the dynamic softening mechanism was flow localization in the form of a shear band and a deformation band caused by adiabatic heating.

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