Grain Size Effect on Mechanical Properties of Titanium Alloy

2014 ◽  
Vol 626 ◽  
pp. 548-552 ◽  
Author(s):  
Cho-Pei Jiang ◽  
Zong Han Huang
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Titanium Alloy ◽  
Size Effect ◽  
Annealing Temperature ◽  
Grain Size Effect ◽  
Β Phase ◽  
Commercially Pure ◽  
Α Phase ◽  
Pure Grade

The aim of this study is to investigate the effect of grain size on mechanical properties of commercially pure grade 2 (CP2) titanium bar with a diameter of 5 mm. The results reveal that the microstructure of β-phase forms when the annealing temperature exceeds 800oC. The formation of β-phase leads to reduce the ductility but increase hardness. The strength coefficient, yielding stress and hardness decrease with increasing of grain size when the microstructure of specimen is the α-phase.

Influences of Solution Temperatures on Microstructure and Mechanical Properties of near α Titanium Alloy

2021 ◽  
Vol 1035 ◽  
pp. 89-95
Author(s):  
Chao Tan ◽  
Zi Yong Chen ◽  
Zhi Lei Xiang ◽  
Xiao Zhao Ma ◽  
Zi An Yang
Keyword(s):  
Mechanical Properties ◽  
Titanium Alloy ◽  
High Temperature ◽  
Room Temperature ◽  
Solution Temperature ◽  
Vacuum Induction Melting ◽  
Induction Melting ◽  
Β Phase ◽  
Α Phase ◽  
New Type

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.

Finite Element Modeling of Grain Size Effect on the Mechanical Properties and Deformability of Titanium Alloy in Equal Channel Angular Pressure

2015 ◽  
Vol 661 ◽  
pp. 91-97
Author(s):  
Cho-Pei Jiang ◽  
Zong Han Huang
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Finite Element ◽  
Titanium Alloy ◽  
Tensile Test ◽  
Annealing Treatment ◽  
Cross Sectional ◽  
Squeeze Pressure ◽  
Brittle Behavior ◽  
Β Phase

The aim of this research is to investigate the effect of grain size on the mechanical properties and deformability of titanium alloy in equal channel and cross-sectional reduction channel angular pressing process. Specimens made of grade 2 titanium alloy with diameter 5 mm are annealed to temperature of 500 °C to 1000 °C resulting in different initial grain sizes, thus underwent tensile test for obtaining mechanical properties. Molds for both processes are designed to carry out serve plastic deformation. Finite element models are created and simulated the deformation behavior according to the mechanical properties of tensile test. Experimental results show that small α-phase grain starts to form in 700 °C homogenization treatment and its grain size increases as an increasing of annealing temperature. The β-phase microstructure precipitates resulting in brittle behavior in 850 °C annealing treatment. Simulation result show that squeeze load of ECAP is larger than 100 ton but it can be reduced when exit angle of channel is larger than entrance. Outer corner of ECAP with 90 ̊ generate lower squeeze pressure than that of 40 ̊.

Effects of Heat Treatment on Microstructures and Mechanical Properties of Ti-38644 Alloy for Aerospace Fasteners

2018 ◽  
Vol 913 ◽  
pp. 109-117 ◽  
Author(s):  
Qing Yun Zhao ◽  
Si Rui Cheng ◽  
Li Dong Wang ◽  
Li Min Dong ◽  
Feng Lei Liu
Keyword(s):  
Mechanical Properties ◽  
Heat Treatment ◽  
Grain Size ◽  
Tensile Strength ◽  
Solution Temperature ◽  
Uniaxial Tensile ◽  
Uniaxial Tensile Test ◽  
Air Cooling ◽  
Β Phase ◽  
Α Phase

The effects of heat treatment on microstructure and mechanical properties of Ti-38644 alloy were investigated by scanning electron microscope (SEM) and transmission electron microscopy (TEM) as well as uniaxial tensile test. The results show that when the solution temperature is lower than 845°C, the microstructure of Ti-38644 alloy is equiaxed β phase with the grain size of 20μm, and the tensile strength is about 960MPa. As raising solution temperature to 860°C, the grain size of Ti-38644 alloy increases to 100μm and the tensile strength decreased to 870MPa. There are a large number of secondary α phase precipitated from the grain boundaries and within grain of β phase undergoing aging treatment. Secondary α phase coarsens with increasing the aging temperature, leading to the decrease of tensile strength. After solution treatment at 815°C for 1.5h, water quenching plus aging at 520°C for 10h, air cooling, Ti-38644 alloy shows a better mechanical property with the tensile strength 1330MPa, elongation and reduction of area 10% and 45% respectively.

Grain size effect of pre- and post-coating treated cemented carbides on PVD films' adhesion and mechanical properties

2013 ◽  
Vol 44 (8) ◽  
pp. 697-703 ◽  
Author(s):  
K.-D. Bouzakis ◽  
N. Michailidis ◽  
G. Skordaris ◽  
A. Tsouknidas ◽  
S. Makrimallakis ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Size Effect ◽  
Cemented Carbides ◽  
Grain Size Effect

Annealing Temperature and Grain Size Effect on the Grain Boundary Ledge (Density) Structure in Nickel

1977 ◽  
Vol 35 ◽  
pp. 286-287
Author(s):  
Eswarahalli Venkatesh
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Grain Boundary ◽  
Grain Boundaries ◽  
Annealing Temperature ◽  
Grain Size Effect ◽  
Density Structure ◽  
Sheet Mill ◽  
Experimental Parameters ◽  
Boundary Ledge

In recent years many researchers have shown great interest in understanding the structure of grain boundaries1,2 and their influence on the mechanical properties of metals and alloys3-5. It has been shown that the structure of grain boundaries can be changed by appropriate thermomechanical treatments6. There are many experimental parameters that can influence the grain boundary ledge structure. The influence of annealing temperature and grain size are considered here.In the present work, pure (99.98%) nickel sheet mill rolled (hot) to 0.022 in. thick was used. One batch of sample was cut and rolled to 40% reduction in thickness and annealed at 800-1125°K in argon,and air cooled to achieve a constant grain size of 50 μm in all samples. A second set of samples was cut and rolled 10-70% reduction in thickness and similarly annealed at 800-1325°K so as to obtain different samples with grain size of 2, 30, 50, and 150 μm.

The Effects of Laser and Mechanical Forming on the Hardness and Microstructural Layout of Commercially Pure Grade 2 Titanium Alloy Plates

2017 ◽  
Author(s):  
Kadephi V. Mjali ◽  
Annelize Els-Botes ◽  
Peter M. Mashinini
Keyword(s):  
Mechanical Properties ◽  
Titanium Alloy ◽  
Scanning Speed ◽  
Grain Structure ◽  
Laser Forming ◽  
Major Influence ◽  
Forming Process ◽  
Commercially Pure ◽  
Profound Influence ◽  
Pure Grade

This paper illustrates the effects of the laser and mechanical forming on the hardness and microstructural distribution in commercially pure grade 2 Titanium alloy plates. The two processes were used to bend commercially pure grade 2 Titanium alloy plates to a similar radius also investigate if the laser forming process could replace the mechanical forming process in the future. The results from both processes are discussed in relation to the mechanical properties of the material. Observations from hardness testing indicate that the laser forming process results in increased hardness in all the samples evaluated, and on the other hand, the mechanical forming process did not influence hardness on the samples evaluated. There was no change in microstructure as a result of the mechanical forming process while the laser forming process had a major influence on the overall microstructure in samples evaluated. The size of the grains became larger with increases in thermal gradient and heat flux, causing changes to the overall mechanical properties of the material. The thermal heat generated has a profound influence on the grain structure and the hardness of Titanium. It is evident that the higher the thermal energy the higher is the hardness, but this only applies up to a power of 2.5kW. Afterwards, there is a reduction in hardness and an increase in grain size. The cooling rate of the plates has been proved to play a significant role in the resulting microstructure of Titanium alloys. The scanning speed plays a role in maintaining the surface temperatures of laser formed Titanium plates resulting in changes to both hardness and the microstructure. An increase in heat results in grain growth affecting the hardness of Titanium.

Grain Size Effect on the Type VT1-0 Alloy Modified by Aluminum Ion Implantation

2015 ◽  
Vol 670 ◽  
pp. 144-151
Author(s):  
Irina Kurzina ◽  
Alisa Nikonenko ◽  
Natalja Popova ◽  
Elena L. Nikonenko ◽  
Mark Kalashnikov
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Ion Implantation ◽  
Size Effect ◽  
Phase State ◽  
Grain Size Effect ◽  
Significant Modification ◽  
Aluminum Ion ◽  
Grain Sizes ◽  
Aluminum Ions

The paper presents results of investigations of α-Ti microhardness modified by aluminum ions having diverse grain sizes, namely: 0.3 μm, 1.5 μm, and 17 μm. These investigations show that the decrease of the grain size and the additional ion implantation result in the significant modification of the structural and phase state of the alloy and its mechanical properties.

Summary of major factors affecting mechanical properties of TiZr based alloys

2015 ◽  
Vol 12 (4) ◽  
pp. 319-324 ◽  
Author(s):  
Lixia Yin ◽  
Shunxing Liang ◽  
Liyun Zheng
Keyword(s):  
Mechanical Properties ◽  
Grain Size ◽  
Test Results ◽  
Factors Affecting ◽  
Β Phase ◽  
Α Phase ◽  
Tc4 Alloy ◽  
Nanoindentation Hardness ◽  
Major Factors ◽  
Zr Alloy

Effects of major factors, such as alloy composition, crystal structure and grain size, on mechanical properties of TiZr based alloys are investigated and summarized in this work. The microhardness of TC4 alloy obviously increases 15.3% and 17.6% after 30 wt.% and 47 wt.% Zr additions, respectively. Nanoindentation results show that the average nanoindentation hardness of α phase in annealed 30 Zr is approximately 18% higher than that of retained β phase. Tensile test results show that variation in strength of basketweave microstructural 30 Zr alloy with original β grain size from 100 to 203 μm is less than 2%.

Sign in / Sign up

Export Citation Format

Share Document