Hot deformation behavior and hot working characteristic of Nickel-base electron beam weldments

Abstract The 60NiTi (Ni60wt%–Ti40wt%) intermetallic is a hard-to-process material. Understanding of hot deformation behavior is crucial for the hot working of 60NiTi. This work studied hot deformation behavior and corresponding microstructure of the hot isostatic pressed 60NiTi in the temperature range of 900 °C–1050 °C and at strain rates of 0.1, 0.01, and 0.001 s-1 through a hot compression test. The flow stress and microstructure were susceptible to the hot deformation parameters. The flow stress decreased with the increase in deformation temperature and decrease in strain rate. Work hardening occurred at a small strain, then followed by softening; finally, near-dynamic equilibrium was achieved between work hardening and softening. A constitutive equation was developed to describe the effects of strain rate and temperature on flow stress. Simulation of hot deformation via the finite element method revealed the workpiece’s inhomogeneous deformation. The deformation occurred mainly in the center area of the cylindrical sample, resulting in high stress and strain concentrations in this region and causing the equiaxial grains to be compressed into prolate grains. This work can provide guidance for the hot working, such as forging and hot rolling, of 60NiTi.

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Influence of δ Phase Content on Hot Deformation Behavior of Ni-Based Superalloy IN718

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.314-316.1159 ◽

2011 ◽

Vol 314-316 ◽

pp. 1159-1162

Author(s):

Hai Yan Zhang ◽

Shi Hong Zhang ◽

Ming Cheng

Keyword(s):

Hot Deformation ◽

Deformation Behavior ◽

Peak Stress ◽

Hot Working ◽

Peak Strain ◽

Phase Content ◽

Compression Tests ◽

Hot Deformation Behavior ◽

Deformation Activation Energy ◽

Δ Phase

The effect of δ phase content on the hot deformation behavior of alloy IN718 has been investigated using isothermal compression tests. The results indicated that the δ phase has a significant effect on the deformation behavior of alloy IN718 during hot working. After the peak stress, the decreasing speed of the stress raises as the increase in the δ phase content. The deformation activation energy for alloy IN718 increases with the raise of the δ phase content. And the peak strain for the alloy decreases with the increase of the δ phase content, which indicates that the δ phase can stimulate the occurrence of dynamic recrystallization during hot working.

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Effect of Precipitation on Hot Deformation Behavior and Processing Maps of Nickel-Base UNS N10276 Alloy

Acta Metallurgica Sinica (English Letters) ◽

10.1007/s40195-017-0635-y ◽

2017 ◽

Vol 30 (11) ◽

pp. 1119-1134 ◽

Cited By ~ 2

Author(s):

En-Xiang Pu ◽

Wen-Jie Zheng ◽

Zhi-Gang Song ◽

Han Feng ◽

Han Dong

Keyword(s):

Hot Deformation ◽

Deformation Behavior ◽

Processing Maps ◽

Hot Deformation Behavior ◽

Nickel Base

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Hot deformation behavior and flow stress modeling of Ti–6Al–4V alloy produced via electron beam melting additive manufacturing technology in single β-phase field

Materials Science and Engineering A ◽

10.1016/j.msea.2020.139822 ◽

2020 ◽

Vol 792 ◽

pp. 139822 ◽

Cited By ~ 3

Author(s):

Abdollah Saboori ◽

Ata Abdi ◽

Seyed Ali Fatemi ◽

Giulio Marchese ◽

Sara Biamino ◽

...

Keyword(s):

Electron Beam ◽

Additive Manufacturing ◽

Flow Stress ◽

Phase Field ◽

Hot Deformation ◽

Deformation Behavior ◽

Electron Beam Melting ◽

Hot Deformation Behavior ◽

Additive Manufacturing Technology ◽

Β Phase

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Hot Deformation Behavior and Microstructural Evolution of PM Ti43Al9V0.3Y with Fine Equiaxed γ and B2 Grain Microstructure

Materials ◽

10.3390/ma13040896 ◽

2020 ◽

Vol 13 (4) ◽

pp. 896

Author(s):

Dongdong Zhang ◽

Yuyong Chen ◽

Guoqing Zhang ◽

Na Liu ◽

Fantao Kong ◽

...

Keyword(s):

Strain Rate ◽

Microstructure Evolution ◽

Hot Deformation ◽

Deformation Behavior ◽

Hot Working ◽

Boundary Slip ◽

Hot Deformation Behavior ◽

Strain And Strain Rate ◽

Working Parameters ◽

Temperature Strain

The hot deformation behavior and microstructure evolution of powder metallurgy (PM) Ti43Al9V0.3Y alloy with fine equiaxed γ and B2 grains were investigated using uniaxial hot compression. Its stress exponent and activation energy were 2.78 and 295.86 kJ/mol, respectively. The efficiency of power dissipation and instability parameters were evaluated, and processing maps at 50% and 80% strains were developed. It is demonstrated that the microstructure evolution was dependent on the temperature, strain, and strain rate. Both temperature and strain increases led to a decrease in the γ phase. Moreover, dynamic recrystallization (DRX) and grain boundary slip both played important roles in deformation. Reasonable parameters for secondary hot working included temperatures above 1100 °C but below 1200 °C with a strain rate of less than 1 s−1 at 80% strain. Suitable hot working parameters at 50% strain were 1150–1200 °C/≤1 s−1 and 1000–1200 °C/≤0.05 s−1.

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