Thermal deformation behavior of γ-TiAl based alloy by plasma hydrogenation

Published on Nov 27, 2020in International Journal of Hydrogen Energy4.939
· DOI :10.1016/J.IJHYDENE.2020.09.008
Fuyu Dong6
Estimated H-index: 6
Liu Yongda + 8 AuthorsJun Cheng1
Estimated H-index: 1
Abstract The Ti–48Al–2Cr alloy was subjected to the plasma-hydrogenation treatment. Then the alloy containing minor hydrogen was prepared (0.058 wt percent, wt.%). Hot-compression experiments were carried out at temperatures ranging from 1000 to 1,150 °C and strain rates ranging from 1 to 0.001 s−1. The results show that the peak stress after the plasma-hydrogenation treatment is lower than that of the unhydrogenated one. At 1100 °C and the strain rate of 0.01 s−1, the peak stress is reduced by 32.3%. The mechanism of high-temperature softening caused by plasma-hydrogenation is examined, and the constitutive equations are established for the unhydrogenated and hydrogenated alloys. Through the constitutive equations, the high-temperature softening mechanism of unhydrogenated and hydrogenated alloys are dynamic-recrystallization, and the activation energy of hydrogenated alloy is lower than that of the unhydrogenated. Meanwhile, electron back-scatter diffraction analyses of the thermal-compressed microstructures show that the hydrogenated alloy has more recrystallized grains, less lamellar structure, and more uniform deformation than the unhydrogenated alloy.
📖 Papers frequently viewed together
5 Authors (李建波, ..., 王岩)
#1Wen Daosheng (UJN: University of Jinan)H-Index: 1
#2Kong Beibei (HIT: Harbin Institute of Technology)H-Index: 1
Last. Zong YingyingH-Index: 2
view all 4 authors...
Abstract Effect of hydrogen on the flow behavior of a TiAl based alloy during plane strain compression at temperatures of 1150 and 1200 °C was investigated in this paper. The results showed that hydrogen obviously softened the alloy and had significant effects on the texture evolution. Hydrogen decreased the number of sharp yield points and hindered the occurrence of Portevin-Le Chatelier effect, which decreased plastic instability of the alloy during plane strain compression. Hydrogen enhanced ...
1 CitationsSource
#1E. N. Stepanova (Tomsk Polytechnic University)H-Index: 8
#2Natalia Pushilina (Tomsk Polytechnic University)H-Index: 6
Last. Egor Kashkarov (Tomsk Polytechnic University)H-Index: 10
view all 5 authors...
Abstract In this work, the hydrogen sorption kinetics as well as the hydrogen effect on phase transformations, structure and properties of additively manufactured Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy using electron beam melting (EBM) were studied. In situ X-ray diffraction complex was used to analyze phase transitions in the EBM Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy under hydrogenation in gas atmosphere. The EBM mode is found to affect significantly on the microstructure and the rate of hydrogen sorption...
5 CitationsSource
#1Xifeng Li (SJTU: Shanghai Jiao Tong University)H-Index: 11
#2Xin Chen (SJTU: Shanghai Jiao Tong University)H-Index: 1
Last. Jun Chen (SJTU: Shanghai Jiao Tong University)H-Index: 18
view all 5 authors...
Abstract The average grain size of Ti-55 titanium alloy is refined by hydrogenation and dehydrogenation treatment from 5.96 μm to 0.5 μm. The refinement mechanism is discussed through microstructural observations. The main refining effects may derive from recrystallization and phase transformation. The micro-strain field in the matrix by the formed hydride during the hydrogenation process results in serious distortion and many dislocations. The recrystallization nucleation and growth during the ...
5 CitationsSource
#1Matthew K. Dunstan (ARL: United States Army Research Laboratory)H-Index: 5
#2James D. Paramore (ARL: United States Army Research Laboratory)H-Index: 11
Last. Pei Sun (UofU: University of Utah)H-Index: 17
view all 4 authors...
Abstract Ti–6Al–4V parts produced using the powder metallurgy process known as hydrogen sintering and phase transformation (HSPT) have been shown to exhibit superior mechanical properties than those produced using traditional titanium powder metallurgy techniques. In this work, the dehydrogenation step of HSPT is investigated as an additional method to further manipulate the microstructure of Ti–6Al–4V. By varying the dehydrogenation temperature, several microstructural features can be controlle...
6 CitationsSource
#1Shiwei Tian (USTB: University of Science and Technology Beijing)H-Index: 3
#2Haitao Jiang (USTB: University of Science and Technology Beijing)H-Index: 14
Last. Shangwu Zeng (USTB: University of Science and Technology Beijing)H-Index: 7
view all 5 authors...
Abstract Hot compression and dynamic recrystallization (DRX) behavior of TiAl alloy (Ti-44Al-4Nb-1.0Mo-0.1B-0.01Y) were investigated by hot compression tests. The tests were conducted at temperature range of 1120–1240 °C with strain rate of 10−3∼1 s−1. Results show that the flow stress during hot compression is affected by deformation temperature and strain rate. The stress exponent n and activation energy Q are measured to be 2.711 and 524.67 kJ/mol, respectively. Critical strain for DRX initia...
16 CitationsSource
#1Qiang Wang (HIT: Harbin Institute of Technology)H-Index: 9
#1Qiang Wang (WUST: Wuhan University of Science and Technology)H-Index: 136
Last. Hengzhi Fu (HIT: Harbin Institute of Technology)H-Index: 35
view all 6 authors...
Abstract The γ-TiAl alloy with a nominal composition of Ti-47Al-2Nb-2Cr-0.2C directionally solidified by electromagnetic cold crucible was isothermally compressed at different temperatures and strain rates. Experimental results revealed that the peak stress decreased with the increased deformation temperature or decreased strain rate. Subgrains were formed in the interior of the lamellae during thermo-compression and the dislocation walls served as the subgrain boundaries. The dynamic recrystall...
7 CitationsSource
#1Vajinder Singh (IITs: Indian Institutes of Technology)H-Index: 3
#1Vajinder Singh (IITs: Indian Institutes of Technology)H-Index: 12
Last. Partha Ghosal (DMRL: Defence Metallurgical Research Laboratory)H-Index: 21
view all 5 authors...
Abstract The characteristics of hot deformation behavior and associated microstructural development of a cast γ-TiAl based Ti-45Al-8Nb-2Cr-0.2B (at.%) alloy have been investigated in the temperature range of 1273–1473 K and the strain rate range of 0.5–0.005 s−1 using a Gleeble thermo-mechanical simulator. The as-cast pancake shows a uniform distribution of fine (α2+γ) and (γ+γ) lamellar colonies with intermittent retained β(B2) and γ grains (average volume fraction: γ = 0.89, α2 = 0.03, and β(B...
18 CitationsSource
#1Damien Connétable (CNRS: Centre national de la recherche scientifique)H-Index: 20
Abstract The present work is a discussion on hydrogen solubility and diffusivity in the TiAl-L10 system using first-principles calculations. First, ground-state properties of the TiAl-L10 system are presented and discussed using elastic, phonon and thermal properties. They are compared with literature results. After having analyzed the geometry of L10 using the space-group theory, ten potential interstitial sites for hydrogen insertion were identified (among which the various octahedral and tetr...
6 CitationsSource
#1Xuejian Lin (SUT: Shenyang University of Technology)H-Index: 1
#2Fuyu Dong (SUT: Shenyang University of Technology)H-Index: 6
Last. Baoshuai HanH-Index: 7
view all 12 authors...
Abstract The hydrogen was straight-forward added to the Ti 6Al 4V/(TiC + TiB) composites (TiC TiB=5 vol.%) by melt hydrogenation. The results of hot compression show that the peak resistance of titanium matrix composites (TMCs) decreased by 17.2% when hydrogen content was 0.035 wt% compared with the TMCs without hydrogen. Therefore, the TMCs with a hydrogen content of 0.035 wt% was performed to a thermal compression experiment. Thermal-deformation characteristics and hot processing map of TMCs w...
11 CitationsSource
#1Wen Daosheng (UJN: University of Jinan)H-Index: 1
#2Kong BeibeiH-Index: 1
Last. Zong Yingying (HIT: Harbin Institute of Technology)H-Index: 2
view all 6 authors...
Abstract The mechanism of hydrogen-restrained crack propagation and practical application of thermohydrogen treatment in a TiAl-based alloy was investigated in this study. Hydrogenated and unhydrogenated alloys were subjected to high-temperature compression test, with a temperature range 1050–1200 °C and strain rate range 0.001–1 s −1 . The results showed that crack propagation was restrained due to hydrogen addition. The main mechanism of hydrogen-restrained crack propagation of such alloy was ...
2 CitationsSource
Cited By0