Crystallization of High Performance Metallic Materials

A special issue of Crystals (ISSN 2073-4352). This special issue belongs to the section "Crystalline Metals and Alloys".

Deadline for manuscript submissions: closed (20 November 2023) | Viewed by 12394

Special Issue Editors

Department of Materials Science and Engineering, KTH Royal Institute of Technology, Brinellvägen 23, SE-10044 Stockholm, Sweden
Interests: microstructure and property correlation of engineering materials; thermophysical property analysis; in situ characterization; sustainable metallurgy; chemical engineering
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Crystallization refers to the process by which a solid phase forms, where atoms or molecules are highly organized into a structure known as a crystal in the matrix. Crystallization of metallic materials normally refers to the solid form during the solidification as well as the subsequent phase transition. Several fundamental aspects considering thermodynamics and kinetics need to be considered for the crystallization mechanism. For the solidification process, a variety of different morphologies of crystalline can be observed, e.g., columnar and equiaxed crystals and dendrites. This solidification understanding can be applied to the casting process as an industrial crystallization. Subsequently, crystallization behaviors can also refer to microstructure evolution in solid-state materials, e.g., austenite decomposition in low-alloy steels. Nucleation and growth as well as interfacial phenomenon are the two scientific issues included in the crystallization process.

The current Special Issue emphasizes crystallization behaviors in high-performance metallic materials. Both solidification and solid-phase transformation are considered, and conventional construction materials, e.g., steels or high-temperature alloys, as well as novel alloy grades, e.g., high entropy alloys, are included. State-of-the-art characterization methods as well as simulation and modelling work regarding crystallization are included. Finally, particle behaviors associated with crystallization, i.e., non-metallic inclusion and precipitate behaviors during solidification and post-process in high-performance alloys are included. In addition, the crystallization behavior of slag and heat flux used for metals’ manufacturing is also included. Authors from academia and industry are therefore invited to submit their original research and review contributions on crystallization of high-performance metallic materials to the current Special Issue.

Dr. Wangzhong Mu
Dr. Chao Chen
Guest Editors

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Keywords

  • solidification of steels and alloys
  • casting process
  • solid-phase transformation
  • high-performance metallic materials
  • in situ characterization
  • nucleation and growth in metals
  • inclusion/precipitate engineering in steels and alloys
  • slag and flux engineering
  • thermodynamics and kinetics of crystallization
  • process–structure–property correlation in alloys

Published Papers (12 papers)

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Research

18 pages, 3486 KiB  
Article
Fatigue and Fracture Behaviors of Short Carbon Fiber Reinforced Squeeze Cast AZ91 at 20 °C and 250 °C
by Nashmi H. Alrasheedi, Mohamed M. El-Sayed Seleman, Mohamed M. Z. Ahmed and Sabbah Ataya
Crystals 2023, 13(10), 1469; https://doi.org/10.3390/cryst13101469 - 09 Oct 2023
Viewed by 580
Abstract
AZ91 is one of the most broadly used Mg alloys because of its good castability and reasonable mechanical properties. Strengthening AZ91 with carbon short fibers aims to increase tensile and fatigue strength, creep, and wear resistance. One of the proposed applications of reinforced [...] Read more.
AZ91 is one of the most broadly used Mg alloys because of its good castability and reasonable mechanical properties. Strengthening AZ91 with carbon short fibers aims to increase tensile and fatigue strength, creep, and wear resistance. One of the proposed applications of reinforced AZ91 is the production of pistons for trucks. Such reciprocating parts are subjected to alternating fatigue loads which can lead to fatigue failure. In this respect, studying the tensile and fatigue behavior of materials subjected to such loading conditions is of great interest. The alternating low-cycle fatigue (LCF) and high-cycle fatigue (HCF) of unreinforced AZ91 and carbon fiber-reinforced AZ91 (AZ91-C) were investigated at 20 °C and 250 °C. Tensile tests were carried out at the same testing temperature to find the appropriate fatigue testing stress and strain for stress-controlled and strain-controlled tests, respectively. The fatigue curves of stress against the number of cycles (S–N) revealed that the composite AZ91-C’s fatigue strength was 55 MPa under HCF, while that of the matrix alloy AZ91 was only 37 MPa at 250 °C. Fracture investigations were conducted on the broken test samples. The fracture approach in the matrix material (AZ91) is mixed ductile/brittle containing fatigue serration, fiber fracture, and separation in the reinforced material (AZ91-C). Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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19 pages, 9147 KiB  
Article
Assessment of the Interatomic Potentials of Beryllium for Mechanical Properties
by Chengzhi Yang, Bin Wu, Wenmin Deng, Shuzhen Li, Jianfeng Jin and Qing Peng
Crystals 2023, 13(9), 1330; https://doi.org/10.3390/cryst13091330 - 30 Aug 2023
Viewed by 783
Abstract
Beryllium finds widespread applications in nuclear energy, where it is required to service under extreme conditions, including high-dose and high-dose rate radiation with constant bombardments of energetic particles leading to various kinds of defects. Though it is generally known that defects give rise [...] Read more.
Beryllium finds widespread applications in nuclear energy, where it is required to service under extreme conditions, including high-dose and high-dose rate radiation with constant bombardments of energetic particles leading to various kinds of defects. Though it is generally known that defects give rise to mechanical degradation, the quantitative relationship between the microstructure and the corresponding mechanical properties remains elusive. Here we have investigated the mechanical properties of imperfect hexagonal close-packed (HCP) beryllium via means of molecular dynamics simulations. We have examined the beryllium crystals with void, a common defect under in-service conditions. We have assessed three types of potentials, including MEAM, Finnis–Sinclair, and Tersoff. The volumetric change with pressure based on MEAM and Tersoff and the volumetric change with temperature based on MEAM are consistent with the experiment. Through cross-comparison on the results from performing hydrostatic compression, heating, and uniaxial tension, the MEAM type potential is found to deliver the most reasonable predictions on the targeted properties. Our atomistic insights might be helpful in atomistic modeling and materials design of beryllium for nuclear energy. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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11 pages, 5969 KiB  
Article
Effect of Pore Defects on Very High Cycle Fatigue Behavior of TC21 Titanium Alloy Additively Manufactured by Electron Beam Melting
by Qingdong Li, Shuai Liu, Binbin Liao, Baohua Nie, Binqing Shi, Haiying Qi, Dongchu Chen and Fangjun Liu
Crystals 2023, 13(9), 1327; https://doi.org/10.3390/cryst13091327 - 30 Aug 2023
Viewed by 645
Abstract
Titanium alloys additively manufactured by electron beam melting (EBM) inevitably obtained some pore defects, which significantly reduced the very high cycle fatigue performance. An ultrasonic fatigue test was carried out on an EBM TC21 titanium alloy with hot isostatic pressing (HIP) and non-HIP [...] Read more.
Titanium alloys additively manufactured by electron beam melting (EBM) inevitably obtained some pore defects, which significantly reduced the very high cycle fatigue performance. An ultrasonic fatigue test was carried out on an EBM TC21 titanium alloy with hot isostatic pressing (HIP) and non-HIP treatment, and the effect of pore defects on the very high cycle fatigue (VHCF) behavior were investigated for the EBM TC21 titanium alloy. The results showed that the S-N curve of non-HIP specimens clearly had a tendency to decrease in very high cycle regimes, and HIP treatment significantly improved fatigue properties. Fatigue limits increased from 250 MPa for non-HIP specimens to 430 MPa for HIP ones. Very high cycle fatigue crack mainly initiated from the internal pore for EBM specimens, and a fine granular area (FGA) was observed at the crack initiation site in a very high cycle regime for both non-HIP and HIP specimens. ΔKFGA had a constant trend in the range from 2.7 MPam to 3.5 MPam, corresponding to the threshold stress intensity factor range for stable crack propagation. The effect of pore defects on the very high cycle fatigue limit was investigated based on the Murakami model. Furthermore, a fatigue indicator parameter (FIP) model based on pore defects was established to predict fatigue life for non-HIP and HIP specimens, which agreed with the experimental data. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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10 pages, 888 KiB  
Article
Nucleation of L12-Al3M (M = Sc, Er, Y, Zr) Nanophases in Aluminum Alloys: A First-Principles ThermodynamicsStudy
by Shuai Liu, Fangjun Liu, Zhanhao Yan, Baohua Nie, Touwen Fan, Dongchu Chen and Yu Song
Crystals 2023, 13(8), 1228; https://doi.org/10.3390/cryst13081228 - 09 Aug 2023
Cited by 1 | Viewed by 717
Abstract
High-performance Sc-containing aluminum alloys are limited in their industrial application due to the high cost of Sc elements. Er, Zr, and Y elements are candidates for replacing Sc elements. Combined with the first-principles thermodynamic calculation and the classical nucleation theory, the nucleation of [...] Read more.
High-performance Sc-containing aluminum alloys are limited in their industrial application due to the high cost of Sc elements. Er, Zr, and Y elements are candidates for replacing Sc elements. Combined with the first-principles thermodynamic calculation and the classical nucleation theory, the nucleation of L12-Al3M (M = Sc, Er, Y, Zr) nanophases in dilutealuminum alloys were investigated to reveal their structural stability. The calculated results showed that the critical radius and nucleation energy of the L12-Al3M phases were as follows: Al3Er > Al3Y > Al3Sc > Al3Zr. The Al3Zr phase was the easiest to nucleate in thermodynamics, while the nucleation of the Al3Y and Al3Er phases were relatively difficult in thermodynamics. Various structures of Al3(Y, Zr) phases with the radius r < 1 nm can coexist in Al-Y-Zr alloys. At a precipitate’s radius of 1–10 nanometers, the core–shelled Al3Zr(Y) phase illustrated the highest nucleation energy, while the separated structure Al3Zr/Al3Y obtained the lowest one, and had thermodynamic advantages in the nucleation process. Moreover, the core–shelled Al3Zr(Y) phase obtained a higher nucleation energy than Al3Zr(Sc) and Al3Zr(Er). Core–doubleshelled Al3Zr/Er(Y) obtained a lower nucleation energy than that of Al3Zr(Y) due to the negative ΔGchem of Al3Er and the negative Al3Er/Al3Y interfacial energy, and was preferentially precipitated in thermodynamics stability. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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15 pages, 8269 KiB  
Article
Effect of Cooling Rate on Crystallization Behavior during Solidification of Hyper Duplex Stainless Steel S33207: An In Situ Confocal Microscopy Study
by Yong Wang and Wangzhong Mu
Crystals 2023, 13(7), 1114; https://doi.org/10.3390/cryst13071114 - 17 Jul 2023
Viewed by 929
Abstract
Hyper duplex stainless steel (HDSS) is a new alloy group of duplex stainless steels with the excellent corrosion resistance and mechanical properties among the existing modern stainless steels. Due to the incorporation of the high content of alloying elements, e.g., Cr, Ni, Mo, [...] Read more.
Hyper duplex stainless steel (HDSS) is a new alloy group of duplex stainless steels with the excellent corrosion resistance and mechanical properties among the existing modern stainless steels. Due to the incorporation of the high content of alloying elements, e.g., Cr, Ni, Mo, etc., the crystallization behavior of δ-ferrite from liquid is of vital importance to be controlled. In this work, the effect of the cooling rate (i.e., 4 °C/min and 150 °C/min) on the nucleation and growth behavior of δ-ferrite in S33207 during the solidification was investigated using a high-temperature confocal scanning laser microscope (HT-CLSM) in combination with electron microscopies and thermodynamic calculations. The obtained results showed that the solidification mode of S33207 steel was a ferrite–austenite type (FA mode). L→δ-ferrite transformation occurred at a certain degree of undercooling, and merging occurred during the growth of the δ-ferrite phase dendrites. Similar microstructure characteristics were observed after solidification under two different cooling rates. The variation in the area fraction of δ-ferrite with different temperatures and time intervals during the solidification of S33207 steels was calculated at different cooling rates. The post-microstructure as well as its composition evolution were also briefly investigated. This work shed light on the real-time insights for the crystallization behavior of hyper duplex stainless steels during their solidification process. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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14 pages, 12910 KiB  
Article
Effects of Ag on High-Temperature Creep Behaviors of Peak-Aged Al-5Cu-0.8Mg-0.15Zr-0.2Sc(-0.5Ag)
by Ying Wang, Ge Zhou, Xin Che, Feng Li and Lijia Chen
Crystals 2023, 13(7), 1096; https://doi.org/10.3390/cryst13071096 - 13 Jul 2023
Viewed by 669
Abstract
The tensile creep of Al-5Cu-0.8Mg-0.15Zr-0.2Sc(-0.5Ag) was tested at 150–250 °C and 125–350 MPa, and the effect of Ag on the high-temperature creep of Al-Cu-Mg alloys was discussed. After the addition of Ag, the high-temperature creep performances of the alloy were significantly improved at [...] Read more.
The tensile creep of Al-5Cu-0.8Mg-0.15Zr-0.2Sc(-0.5Ag) was tested at 150–250 °C and 125–350 MPa, and the effect of Ag on the high-temperature creep of Al-Cu-Mg alloys was discussed. After the addition of Ag, the high-temperature creep performances of the alloy were significantly improved at 150 °C/300 MPa and 200 °C/(150 MPa, 175 MPa). Then, constitutive relational models of the alloy during high-temperature creep were built, and the activation energy was calculated to be 136.65 and 104.06 KJ/mol. Based on the thermal deformation mechanism maps, the high-temperature creep mechanism of the alloy was predicted. After the addition of Ag, the creep mechanism of the alloy at 150 °C transitioned from lattice diffusion control to grain boundary diffusion control. At 250 °C, the mechanism was still controlled by grain boundary slip, but as the stress index increased and after Ag was added, the alloy fractures lead to the formation of dimples, thus improving the high-temperature creep performance. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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13 pages, 15815 KiB  
Article
Microstructure, Mechanical Properties and Thermal Stability of Ni-Based Single Crystal Superalloys with Low Specific Weight
by Dengyu Liu, Qingqing Ding, Qian Zhou, Dingxin Zhou, Xiao Wei, Xinbao Zhao, Ze Zhang and Hongbin Bei
Crystals 2023, 13(4), 610; https://doi.org/10.3390/cryst13040610 - 02 Apr 2023
Cited by 1 | Viewed by 1497
Abstract
Ni-based single crystal (SX) superalloy with low specific weight is vital for developing aero engines with a high strength-to-weight ratio. Based on an alloy system with 3 wt.% Re but without W, namely Ni-Co-Cr-Mo-Ta-Re-Al-Ti, a specific weight below 8.4 g/cm3 has been [...] Read more.
Ni-based single crystal (SX) superalloy with low specific weight is vital for developing aero engines with a high strength-to-weight ratio. Based on an alloy system with 3 wt.% Re but without W, namely Ni-Co-Cr-Mo-Ta-Re-Al-Ti, a specific weight below 8.4 g/cm3 has been achieved. To reveal the relationship among the composition, mechanical properties, and thermal stability of Ni-based SX superalloys, SXs with desirable microstructures are fabricated. Tensile tests revealed that the SX alloys have comparable strength to commercial second-generation SX CMSX-4 (3 wt.% Re and 6 wt.% W) and Rene′ N5 alloys (3 wt.% Re and 5 wt.% W) above 800 °C. Moreover, the elongation to fracture (EF) below 850 °C (>20%) is better than that of those two commercial SX superalloys. During thermal exposure at 1050 °C for up to 500 h, the topological close-packed (TCP) phase does not appear, indicating excellent phase stability. Decreasing Al concentration increases the resistance of γ′ rafting and replacing 1 wt.% Ti with 3 wt.% Ta is beneficial to the stability of the shape and size of γ′ phase during thermal exposure. The current work might provide scientific insights for developing Ni-based SX superalloys with low specific weight. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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12 pages, 10121 KiB  
Article
The Effect of Interatomic Potentials on the Nature of Nanohole Propagation in Single-Crystal Nickel: A Molecular Dynamics Simulation Study
by Xinmao Qin, Yilong Liang, Jiabao Gu and Guigui Peng
Crystals 2023, 13(4), 585; https://doi.org/10.3390/cryst13040585 - 29 Mar 2023
Cited by 1 | Viewed by 970
Abstract
Based on a molecular dynamics (MD) simulation, we investigated the nanohole propagation behaviors of single-crystal nickel (Ni) under different styles of Ni–Ni interatomic potentials. The results show that the MEAM (the modified embedded atom method potential) potential is best suited to describe the [...] Read more.
Based on a molecular dynamics (MD) simulation, we investigated the nanohole propagation behaviors of single-crystal nickel (Ni) under different styles of Ni–Ni interatomic potentials. The results show that the MEAM (the modified embedded atom method potential) potential is best suited to describe the brittle propagation behavior of nanoholes in single-crystal Ni. The EAM/FS (embedded atom method potential developed by Finnis and Sinclair) potential, meanwhile, is effective at characterizing the plastic growth behavior of nanoholes in single-crystal Ni. Furthermore, the results show the difference between the different styles of interatomic potentials in characterizing nanohole propagation in single-crystal Ni and provide a theoretical basis for the selection of interatomic potentials in the MD simulation of Ni crystals. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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17 pages, 9527 KiB  
Article
High Temperature Deformation Behavior of Near-β Titanium Alloy Ti-3Al-6Cr-5V-5Mo at α + β and β Phase Fields
by Haoyu Zhang, Shuo Zhang, Shuai Zhang, Xuejia Liu, Xiaoxi Wu, Siqian Zhang and Ge Zhou
Crystals 2023, 13(3), 371; https://doi.org/10.3390/cryst13030371 - 21 Feb 2023
Cited by 1 | Viewed by 919
Abstract
Most near-β titanium alloy structural components should be plastically deformed at high temperatures. Inappropriate high-temperature deformed processes can lead to macro-defects and abnormally coarse grains. Ti-3Al-6Cr-5V-5Mo alloy is a near-β titanium alloy with the potential application. The available information on the high-temperature deformation [...] Read more.
Most near-β titanium alloy structural components should be plastically deformed at high temperatures. Inappropriate high-temperature deformed processes can lead to macro-defects and abnormally coarse grains. Ti-3Al-6Cr-5V-5Mo alloy is a near-β titanium alloy with the potential application. The available information on the high-temperature deformation behavior of the alloy is limited. To provide guidance for the actual hot working of the alloy, the flow stress behavior and processing map at α + β phase field and β phase field were studied, respectively. Based on the experimental data obtained from hot compressing simulations at the range of temperature from 700 °C to 820 °C and at the range of strain rate from 0.001 s−1 to 10 s−1, the constitutive models, as well as the processing map, were obtained. For the constitutive models at the α + β phase field and β phase field, the correlated coefficients between actual stress and predicted stress are 0.986 and 0.983, and the predictive mean relative errors are 2.7% and 4.1%. The verification of constitutive models demonstrates that constitutive equations can predict flow stress well. An instability region in the range of temperature from 700 °C to 780 °C and the range of strain rates from 0.08 s−1 to 10 s−1, as well as a suitable region for thermomechanical processing in the range of temperature from 790 °C to 800 °C and the range of strain rates from 0.001 s−1 to 0.007 s−1, was predicted by the processing map and confirmed by the hot-deformed microstructural verification. After the deformation at 790 °C/0.001 s−1, the maximum number of dynamic recrystallization grains and the minimum average grain size of 17 μm were obtained, which is consistent with the high power-dissipation coefficient region predicted by the processing map. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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14 pages, 6783 KiB  
Article
Vacuum Electrodeposition of Cu(In, Ga)Se2 Thin Films and Controlling the Ga Incorporation Route
by Kanwen Hou, Guohao Liu, Jia Yang, Wei Wang, Lixin Xia, Jun Zhang, Baoqiang Xu and Bin Yang
Crystals 2023, 13(2), 319; https://doi.org/10.3390/cryst13020319 - 15 Feb 2023
Cited by 1 | Viewed by 1212
Abstract
The traditional electrochemical deposition process used to prepare Cu(In, Ga)Se2 (CIGS) thin films has inherent flaws, such as the tendency to produce low-conductivity Ga2O3 phase and internal defects. In this article, CIGS thin films were prepared under vacuum (3 [...] Read more.
The traditional electrochemical deposition process used to prepare Cu(In, Ga)Se2 (CIGS) thin films has inherent flaws, such as the tendency to produce low-conductivity Ga2O3 phase and internal defects. In this article, CIGS thin films were prepared under vacuum (3 kPa), and the mechanism of vacuum electrodeposition CIGS was illustrated. The route of Ga incorporation into the thin films could be controlled in a vacuum environment via inhibiting pH changes at the cathode region. Through the incorporation of a low-conductivity secondary phase, Ga2O3 was inhibited at 3 kPa, as shown by Raman and X-ray photoelectron spectroscopy. The preparation process used a higher current density and a lower diffusion impedance and charge transfer impedance. The films that were produced had larger particle sizes. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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19 pages, 6616 KiB  
Article
Elastic Constitutive Relationship of Metallic Materials Containing Grain Shape
by Zhiwen Lan, Hanjie Shao, Lei Zhang, Hong Yan, Mojia Huang and Tengfei Zhao
Crystals 2022, 12(12), 1768; https://doi.org/10.3390/cryst12121768 - 05 Dec 2022
Viewed by 1149
Abstract
The grain shape and orientation distribution of metal sheets at mesoscales are usually irregular, which has an impact on the elastic properties of metal materials. A grain shape function (GSF) is constructed to represent the shape of grains. The expansion coefficient of GSF [...] Read more.
The grain shape and orientation distribution of metal sheets at mesoscales are usually irregular, which has an impact on the elastic properties of metal materials. A grain shape function (GSF) is constructed to represent the shape of grains. The expansion coefficient of GSF on the basis of the Wigner D function is called the shape coefficient. In this paper, we study the influence of average grain shape on the elastic constitutive relation of orthogonal polycrystalline materials, and obtain a new expression of the elastic constitutive relation of polycrystalline materials containing grain shape effects. The seven string method is proposed to fit the shape of irregular grains. Experiments show that the GSF can better describe the shape of irregular grains. Using the microscopic images of the grains, we carried out the experimental measurement of micro and macrostrain at grain scale. The experimental results show that the grain shape parameter (slenderness ratio) is consistent with the theoretical results of the material macroscopic mechanical properties. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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13 pages, 6894 KiB  
Article
Electronic Structure and Optical Properties of Cu2ZnSnS4 under Stress Effect
by Xiufan Yang, Xinmao Qin, Wanjun Yan, Chunhong Zhang, Dianxi Zhang and Benhua Guo
Crystals 2022, 12(10), 1454; https://doi.org/10.3390/cryst12101454 - 14 Oct 2022
Viewed by 1113
Abstract
By using the pseudopotential plane-wave method of first principles based on density functional theory, the band structure, density of states and optical properties of Cu2ZnSnS4 under isotropic stress are calculated and analyzed. The results show that Cu2ZnSnS4 [...] Read more.
By using the pseudopotential plane-wave method of first principles based on density functional theory, the band structure, density of states and optical properties of Cu2ZnSnS4 under isotropic stress are calculated and analyzed. The results show that Cu2ZnSnS4 is a direct band gap semiconductor under isotropic stress, the lattice is tetragonal, and the band gap of Cu2ZnSnS4 is 0.16 eV at 0 GPa. Stretching the lattice causes the bottom of the conduction band of Cu2ZnSnS4 to move toward lower energies, while the top of the valence band remains unchanged and the band gap gradually narrows. Squeezing the lattice causes the bottom of the conduction band to move toward the high-energy direction, while the top of the valence band moves downward toward the low-energy direction, and the Cu2ZnSnS4 band gap becomes larger. The static permittivity, absorption coefficient, reflectivity, refractive index, electrical conductivity, and energy loss function all decrease when the lattice is stretched, and the above optical parameters increase when the lattice is compressed. When the lattice is stretched, the optical characteristic peaks such as the dielectric function shift to the lower-energy direction, while the optical characteristic peak position shifts to the higher-energy direction when the lattice is compressed. Full article
(This article belongs to the Special Issue Crystallization of High Performance Metallic Materials)
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