Ab Initio Study of Elastic and Mechanical Properties in FeCrMn Alloys

Mechanical properties of FeCrMn-based steels are of major importance for practical applications. In this work, we investigate mechanical properties of disordered paramagnetic fcc FeCr 10 – 16 Mn 12 – 32 alloys using density functional theory. The effects of composition and temperature changes on the magnetic state, elastic properties and stacking fault energies of the alloys are studied. Calculated dependencies of the lattice and elastic constants are used to evaluate the effect of the solid solution strengthening by Mn and Cr using a modified Labusch-Nabarro model and a model for concentrated alloys. The effect of Cr and Mn alloying on the stacking fault energies is calculated and discussed in connection to possible deformation mechanisms.

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Ab Initio Calculation of Mechanical Properties of Stacking Fault in 3C-SiC: Effect of Stress and Doping

Materials Science Forum ◽

10.4028/www.scientific.net/msf.717-720.415 ◽

2012 ◽

Vol 717-720 ◽

pp. 415-418

Author(s):

Yoshitaka Umeno ◽

Kuniaki Yagi ◽

Hiroyuki Nagasawa

Keyword(s):

Mechanical Properties ◽

Ab Initio ◽

Density Functional ◽

Stacking Faults ◽

Single Layer ◽

Local Strain ◽

Density Functional Theory Calculations ◽

Stacking Fault ◽

Functional Theory ◽

N Doping

We carry out ab initio density functional theory calculations to investigate the fundamental mechanical properties of stacking faults in 3C-SiC, including the effect of stress and doping atoms (substitution of C by N or Si). Stress induced by stacking fault (SF) formation is quantitatively evaluated. Extrinsic SFs containing double and triple SiC layers are found to be slightly more stable than the single-layer extrinsic SF, supporting experimental observation. Effect of tensile or compressive stress on SF energies is found to be marginal. Neglecting the effect of local strain induced by doping, N doping around an SF obviously increase the SF formation energy, while SFs seem to be easily formed in Si-rich SiC.

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Generalised stacking fault energies of copper alloys - density functional theory calculations

Journal of Mining and Metallurgy Section B Metallurgy ◽

10.2298/jmmb181128020m ◽

2019 ◽

Vol 55 (2) ◽

pp. 271-282

Author(s):

M. Muzyk ◽

K.J. Kurzydłowski

Keyword(s):

Density Functional Theory ◽

Transition Metal ◽

Density Functional ◽

Copper Alloys ◽

Density Functional Theory Calculations ◽

Stacking Fault ◽

Alloying Element ◽

Functional Theory ◽

Work Hardening Rate ◽

Stacking Fault Energies

Generalised stacking fault energies of copper alloys have been calculated using density functional theory. Stacking fault energy of copper alloys is correlated with the d?electrons number of transition metal alloying element. The tendency to twiningis also modified by the presence of alloying element in the deformation plane. The results suggest that Cu ?transition metal alloys with such elements as Cr, Mo, W, Mn, Re are expected to exhibit great work hardening rate due to the tendency to emission of the partial dislocations.

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Decoupling between Shockley partials and stacking faults strengthens multiprincipal element alloys

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2114167118 ◽

2021 ◽

Vol 118 (51) ◽

pp. e2114167118

Author(s):

Zongrui Pei ◽

Siyuan Zhang ◽

Yinkai Lei ◽

Fan Zhang ◽

Mingwei Chen

Keyword(s):

Mechanical Properties ◽

Density Functional ◽

Stacking Faults ◽

Decisive Role ◽

Atomistic Simulations ◽

High Yield ◽

Functional Theory ◽

Partial Dislocations ◽

High Resolution Microscopy ◽

Stacking Fault Energies

Mechanical properties are fundamental to structural materials, where dislocations play a decisive role in describing their mechanical behavior. Although the high-yield stresses of multiprincipal element alloys (MPEAs) have received extensive attention in the last decade, the relation between their mechanistic origins remains elusive. Our multiscale study of density functional theory, atomistic simulations, and high-resolution microscopy shows that the excellent mechanical properties of MPEAs have diverse origins. The strengthening effects through Shockley partials and stacking faults can be decoupled in MPEAs, breaking the conventional wisdom that low stacking fault energies are coupled with wide partial dislocations. This study clarifies the mechanistic origins for the strengthening effects, laying the foundation for physics-informed predictive models for materials design.

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Generalized Stacking Fault Energies of Aluminum Alloys–Density Functional Theory Calculations

Metals ◽

10.3390/met8100823 ◽

2018 ◽

Vol 8 (10) ◽

pp. 823 ◽

Cited By ~ 11

Author(s):

Marek Muzyk ◽

Zbigniew Pakieła ◽

Krzysztof J. Kurzydłowski

Keyword(s):

Density Functional Theory ◽

Aluminum Alloys ◽

Density Functional ◽

Density Functional Theory Calculations ◽

Stacking Fault ◽

Functional Theory ◽

Partial Dislocations ◽

Work Hardening Rate ◽

Generalized Stacking Fault ◽

Stacking Fault Energies

Generalized stacking fault energies of aluminum alloys were calculated using density functional theory. Stacking fault energy of aluminum alloys was correlated with the d-electrons number of transition metal alloying elements. The tendency to twinning is also modified by the presence of the alloying element in the deformation plane. Our results suggest that Al alloys, with such elements as Zr, Nb, Y, Mo, Ta, and Hf, are expected to exhibit a strong work hardening rate due to emission of the partial dislocations.

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Novel Co-Cu-Based Immiscible Medium-Entropy Alloys with Promising Mechanical Properties

Metals ◽

10.3390/met11020238 ◽

2021 ◽

Vol 11 (2) ◽

pp. 238

Author(s):

Sujung Son ◽

Jongun Moon ◽

Hyeonseok Kwon ◽

Peyman Asghari Rad ◽

Hidemi Kato ◽

...

Keyword(s):

Mechanical Properties ◽

Binary System ◽

Design Methodology ◽

Miscibility Gap ◽

Face Centered Cubic ◽

Solid Solution Strengthening ◽

Solution Strengthening ◽

Face Centered ◽

Strength And Ductility ◽

Cobalt Copper

New AlxCo50−xCu50−xMnx (x = 2.5, 10, and 15 atomic %, at%) immiscible medium-entropy alloys (IMMEAs) were designed based on the cobalt-copper binary system. Aluminum, a strong B2 phase former, was added to enhance yield strength and ultimate tensile strength, while manganese was added for additional solid solution strengthening. In this work, the microstructural evolution and mechanical properties of the designed Al-Co-Cu-Mn system are examined. The alloys exhibit phase separation into dual face-centered cubic (FCC) phases due to the miscibility gap of the cobalt-copper binary system with the formation of CoAl-rich B2 phases. The hard B2 phases significantly contribute to the strength of the alloys, whereas the dual FCC phases contribute to elongation mitigating brittle fracture. Consequently, analysis of the Al-Co-Cu-Mn B2-strengthened IMMEAs suggest that the new alloy design methodology results in a good combination of strength and ductility.

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A Short Review on the Phase Structures, Oxidation Kinetics, and Mechanical Properties of Complex Ti-Al Alloys

Materials ◽

10.3390/ma14071677 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1677

Author(s):

Hooi Peng Lim ◽

Willey Yun Hsien Liew ◽

Gan Jet Hong Melvin ◽

Zhong-Tao Jiang

Keyword(s):

Mechanical Properties ◽

Oxidation Kinetics ◽

Mass Gain ◽

Short Review ◽

Al Alloys ◽

Alloying Elements ◽

Isothermal Exposure ◽

Solid Solution Strengthening ◽

Phase Structures ◽

Solution Strengthening

This paper reviews the phase structures and oxidation kinetics of complex Ti-Al alloys at oxidation temperatures in the range of 600–1000 °C. The mass gain and parabolic rate constants of the alloys under isothermal exposure at 100 h (or equivalent to cyclic exposure for 300 cycles) is compared. Of the alloying elements investigated, Si appeared to be the most effective in improving the oxidation resistance of Ti-Al alloys at high temperatures. The effect of alloying elements on the mechanical properties of Ti-Al alloys is also discussed. Significant improvement of the mechanical properties of Ti-Al alloys by element additions has been observed through the formation of new phases, grain refinement, and solid solution strengthening.

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Effect of Ti Element on Microstructure and Properties of Cu-Cr Alloy

Materials Science Forum ◽

10.4028/www.scientific.net/msf.817.307 ◽

2015 ◽

Vol 817 ◽

pp. 307-311 ◽

Cited By ~ 5

Author(s):

Peng Chao Zhang ◽

Jin Chuan Jie ◽

Yuan Gao ◽

Tong Min Wang ◽

Ting Ju Li

Keyword(s):

Mechanical Properties ◽

Solid Solution ◽

Spherical Shape ◽

Precipitation Strengthening ◽

Peak Hardness ◽

Ti Alloy ◽

Strengthening Mechanisms ◽

Vacuum Melting ◽

Solid Solution Strengthening ◽

Solution Strengthening

The Cu-Cr and Cu-Cr-Ti alloy plates were prepared by vacuum melting and plastic deformation. The effect of slight Ti element on microstructure and mechanical properties of Cu-Cr alloy was discussed. The result shows that Cr particles with spherical shape precipitated from Cu matrix after aging. Plenty Ti atoms dissolved in the vicinity of Cr particles and there were still parts of solid solution Ti atoms in other regions. Improvements in peak hardness and softening resistance were achieved with the addition of Ti element in Cu-Cr alloy. The addition of 0.1 wt.% Ti element makes Cu-Cr alloy possess tensile strength of 565 MPa and hardness of 185.9 HV after aging at 450 °C for 120 min, which can be attributed to multiple strengthening mechanisms, i.e. work hardening, solid solution strengthening and precipitation strengthening.

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