Unveiling the cellular microstructure–property relations in maraging steel via laser powder bed fusion

Lingzhi Wu; Cong Zhang; Dil Faraz Khan; Ruijie Zhang; Yongwei Wang; Xue Jiang; Haiqing Yin; Xuanhui Qu; Geng Liu; Jie Su

doi:10.1007/s12613-024-2947-z

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Lingzhi Wu, Cong Zhang, Dil Faraz Khan, Ruijie Zhang, Yongwei Wang, Xue Jiang, Haiqing Yin, Xuanhui Qu, Geng Liu, and Jie Su, Unveiling the cellular microstructure–property relations in maraging steel via laser powder bed fusion, Int. J. Miner. Metall. Mater.,(2024). https://doi.org/10.1007/s12613-024-2947-z

Cite this article as:

Lingzhi Wu, Cong Zhang, Dil Faraz Khan, Ruijie Zhang, Yongwei Wang, Xue Jiang, Haiqing Yin, Xuanhui Qu, Geng Liu, and Jie Su, Unveiling the cellular microstructure–property relations in maraging steel via laser powder bed fusion, Int. J. Miner. Metall. Mater.,(2024). https://doi.org/10.1007/s12613-024-2947-z

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Research Article

Unveiling the cellular microstructure–property relations in maraging steel via laser powder bed fusion

+ Author Affiliations

Corresponding authors:
Cong Zhang    E-mail: zhangcong@ustb.edu.cn

Ruijie Zhang    E-mail: zrj@ustb.edu.cn

Haiqing Yin    E-mail: hqyin@ustb.edu.cn
Received: 25 March 2024; Revised: 28 May 2024; Accepted: 29 May 2024; Available online: 30 May 2024

Abstract

Abstract

Additive manufacturing enables rapid fabrication of complex components through layer-by-layer formation. At present, there is a paucity of addressing the effects on cellular microstructures and mechanical properties during the process of laser powder bed fusion (LPBF). Therefore, this study systematically investigated the influence of cellular microstructure and mechanical properties response of maraging steel by LPBF. Increasing the laser scanning speed does not lead to a noticeable change in the phase fraction, but it reduces the average size of the cellular structure from 0.60 to 0.35 μm. The scanning speed is 400 and 1000 mm/s are both have adverse effects on performance, resulting in inadequate fusion and keyhole defects, respectively. The optimal scanning speed for fabricating samples is determined to be 800 mm/s, which exhibits the highest room temperature tensile strength and elongation. The ultimate tensile strength measures at (1088.3 ± 2.0) MPa, with an elongation of (16.76 ± 0.10)%. The mechanism of the evolution of surface morphology, defects, and energy input were clarified, the relationship between cellular structure size and mechanical property was also established.
- laser powder bed fusion;
- maraging steel;
- cellular microstructure;
- mechanical properties;
- strengthening mechanism

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[1]	Z.Y. Liu, D.D. Zhao, P. Wang, et al., Additive manufacturing of metals: Microstructure evolution and multistage control, J. Mater. Sci. Technol., 100(2022), p. 224. doi: 10.1016/j.jmst.2021.06.011
[2]	H.L. Cheng, X.C. Luo, and X. Wu, Recent research progress on additive manufacturing of high-strength low-alloy steels: Focusing on the processing parameters, microstructures and properties, Mater. Today Commun., 36(2023), art. No. 106616. doi: 10.1016/j.mtcomm.2023.106616
[3]	J. Fu, H. Li, X. Song, and M.W. Fu, Multi-scale defects in powder-based additively manufactured metals and alloys, J. Mater. Sci. Technol., 122(2022), p. 165. doi: 10.1016/j.jmst.2022.02.015
[4]	M. Simonelli, Z.Y. Zou, P. Barriobero-Vila, and Y.Y. Tse, The development of ultrafine grain structure in an additively manufactured titanium alloy via high-temperature microscopy, Materialia, 30(2023), art. No. 101856. doi: 10.1016/j.mtla.2023.101856
[5]	T. DebRoy, H.L. Wei, J.S. Zuback, et al., Additive manufacturing of metallic components–Process, structure and properties, Prog. Mater. Sci., 92(2018), p. 112. doi: 10.1016/j.pmatsci.2017.10.001
[6]	J.L. Cann, A. De Luca, D.C. Dunand, et al., Sustainability through alloy design: Challenges and opportunities, Prog. Mater. Sci., 117(2021), art. No. 100722. doi: 10.1016/j.pmatsci.2020.100722
[7]	C.L. Tan, K.S. Zhou, W.Y. Ma, P.P. Zhang, M. Liu, and T.C. Kuang, Microstructural evolution, nanoprecipitation behavior and mechanical properties of selective laser melted high-performance grade 300 maraging steel, Mater. Des., 134(2017), p. 23. doi: 10.1016/j.matdes.2017.08.026
[8]	J.R. Lee, M.S. Lee, H. Chae, et al., Effects of building direction and heat treatment on the local mechanical properties of direct metal laser sintered 15-5 PH stainless steel, Mater. Charact., 167(2020), art. No. 110468. doi: 10.1016/j.matchar.2020.110468
[9]	G. Liu, J. Su, A. Wang, et al., A novel Fe–Cr–Ni–Co–Mo maraging stainless steel with enhanced strength and cryogenic toughness: Role of austenite with core-shell structures, Mater. Sci. Eng. A, 863(2023), art. No. 144537. doi: 10.1016/j.msea.2022.144537
[10]	D.H. Liu, J. Su, A. Wang, et al., Tailoring the microstructure and mechanical properties of FeCrNiCoMo maraging stainless steel after laser melting deposition, Mater. Sci. Eng. A, 840(2022), art. No. 142931. doi: 10.1016/j.msea.2022.142931
[11]	L.Z. Wu, D.F. Khan, C. Zhang, et al., Microstructure and mechanical characterization of additively manufactured Fe11Cr8Ni5Co3Mo martensitic stainless steel, Mater. Charact., 203(2023), art. No. 113106. doi: 10.1016/j.matchar.2023.113106
[12]	D.D. Dong, C. Chang, H. Wang, et al., Selective laser melting (SLM) of CX stainless steel: Theoretical calculation, process optimization and strengthening mechanism, J. Mater. Sci. Technol., 73(2021), p. 151. doi: 10.1016/j.jmst.2020.09.031
[13]	Y.X. Geng, H. Tang, J.H. Xu, et al., Influence of process parameters and aging treatment on the microstructure and mechanical properties of AlSi8Mg3 alloy fabricated by selective laser melting, Int. J. Miner. Metall. Mater., 29(2022), No. 9, p. 1770. doi: 10.1007/s12613-021-2287-1
[14]	G.Q. Dai, M.H. Xue, Y.H. Guo, et al., Gradient microstructure and strength-ductility synergy improvement of 2319 aluminum alloys by hybrid additive manufacturing, J. Alloys Compd., 968(2023), art. No. 171781. doi: 10.1016/j.jallcom.2023.171781
[15]	M.W. Vaughan, M. Elverud, J. Ye, et al., Development of a process optimization framework for fabricating fully dense advanced high strength steels using laser directed energy deposition, Addit. Manuf., 67(2023), art. No. 103489.
[16]	X.D. Nong, X.L. Zhou, J.H. Li, Y.D. Wang, Y.F. Zhao, and M. Brochu, Selective laser melting and heat treatment of precipitation hardening stainless steel with a refined microstructure and excellent mechanical properties, Scripta Mater., 178(2020), p. 7. doi: 10.1016/j.scriptamat.2019.10.040
[17]	W. Abd-Elaziem, S. Elkatatny, A.E. Abd-Elaziem, et al., On the current research progress of metallic materials fabricated by laser powder bed fusion process: A review, J. Mater. Res. Technol., 20(2022), p. 681. doi: 10.1016/j.jmrt.2022.07.085
[18]	W. Abd-Elaziem, S. Elkatatny, T.A. Sebaey, M.A. Darwish, M.A. Abd El-Baky, and A. Hamada, Machine learning for advancing laser powder bed fusion of stainless steel, J. Mater. Res. Technol., 30(2024), p. 4986. doi: 10.1016/j.jmrt.2024.04.130
[19]	Q. Chen, L.Y. Xu, L. Zhao, K.D. Hao, and Y.D. Han, Effect of scanning speed on microstructure and mechanical properties of as-printed Ti–22Al–25Nb intermetallic by laser powder bed fusion, Mater. Sci. Eng. A, 885(2023), art. No. 145652. doi: 10.1016/j.msea.2023.145652
[20]	E. Liverani, S. Toschi, L. Ceschini, and A. Fortunato, Effect of selective laser melting (SLM) process parameters on microstructure and mechanical properties of 316L austenitic stainless steel, J. Mater. Process. Technol., 249(2017), p. 255. doi: 10.1016/j.jmatprotec.2017.05.042
[21]	L. Hao, W.L. Wang, J. Zeng, M. Song, S. Chang, and C.Y. Zhu, Effect of scanning speed and laser power on formability, microstructure, and quality of 316L stainless steel prepared by selective laser melting, J. Mater. Res. Technol., 25(2023), p. 3189. doi: 10.1016/j.jmrt.2023.06.144
[22]	M. Sanjari, A. Hadadzadeh, H. Pirgazi, et al., Selective laser melted stainless steel CX: Role of built orientation on microstructure and micro-mechanical properties, Mater. Sci. Eng. A, 786(2020), art. No. 139365. doi: 10.1016/j.msea.2020.139365
[23]	J.W. Liu, Y.N. Song, C.Y. Chen, et al., Effect of scanning speed on the microstructure and mechanical behavior of 316L stainless steel fabricated by selective laser melting, Mater. Des., 186(2020), art. No. 108355. doi: 10.1016/j.matdes.2019.108355
[24]	G.N. Nigon, O. Burkan Isgor, and S. Pasebani, The effect of annealing on the selective laser melting of 2205 duplex stainless steel: Microstructure, grain orientation, and manufacturing challenges, Opt. Laser Technol., 134(2021), art. No. 106643. doi: 10.1016/j.optlastec.2020.106643
[25]	P.F. Jiang, C.H. Zhang, S. Zhang, J.B. Zhang, J. Chen, and H.T. Chen, Additive manufacturing of novel ferritic stainless steel by selective laser melting: Role of laser scanning speed on the formability, microstructure and properties, Opt. Laser Technol., 140(2021), art. No. 107055. doi: 10.1016/j.optlastec.2021.107055
[26]	T.H. Hsu, P.C. Huang, M.Y. Lee, et al., Effect of processing parameters on the fractions of martensite in 17-4 PH stainless steel fabricated by selective laser melting, J. Alloys Compd., 859(2021), art. No. 157758. doi: 10.1016/j.jallcom.2020.157758
[27]	A. Hamada, M. Jaskari, T. Gundgire, and A. Järvenpää, Enhancement and underlying fatigue mechanisms of laser powder bed fusion additive-manufactured 316L stainless steel, Mater. Sci. Eng. A, 873(2023), art. No. 145021. doi: 10.1016/j.msea.2023.145021
[28]	S. Giganto, S. Martínez-Pellitero, J. Barreiro, P. Leo, and M.Á. Castro-Sastre, Impact of the laser scanning strategy on the quality of 17-4PH stainless steel parts manufactured by selective laser melting, J. Mater. Res. Technol., 20(2022), p. 2734. doi: 10.1016/j.jmrt.2022.08.040
[29]	T.H. Hsu, Y.J. Chang, C.Y. Huang, et al., Microstructure and property of a selective laser melting process induced oxide dispersion strengthened 17-4 PH stainless steel, J. Alloys Compd., 803(2019), p. 30. doi: 10.1016/j.jallcom.2019.06.289
[30]	W.P. Wu, X. Wang, Q. Wang, et al., Microstructure and mechanical properties of maraging 18Ni-300 steel obtained by powder bed based selective laser melting process, Rapid Prototyping J., 26(2020), No. 8, p. 1379. doi: 10.1108/RPJ-08-2018-0189
[31]	J. Song, Q. Tang, Q.X. Feng, et al., Effect of remelting processes on the microstructure and mechanical behaviours of 18Ni-300 maraging steel manufactured by selective laser melting, Mater. Charact., 184(2022), art. No. 111648. doi: 10.1016/j.matchar.2021.111648
[32]	Z.C. Liu, H. Kim, W.W. Liu, W.L. Cong, Q.H. Jiang, and H.C. Zhang, Influence of energy density on macro/micro structures and mechanical properties of as-deposited Inconel 718 parts fabricated by laser engineered net shaping, J. Manuf. Process., 42(2019), p. 96. doi: 10.1016/j.jmapro.2019.04.020
[33]	T. Rautio, A. Hamada, J. Kumpula, A. Järvenpää, and T. Allam, Enhancement of electrical conductivity and corrosion resistance by silver shell–copper core coating of additively manufactured AlSi₁₀Mg alloy, Surf. Coat. Technol., 403(2020), art. No. 126426. doi: 10.1016/j.surfcoat.2020.126426
[34]	S.D. Wang, J.H. Wang, S.J. Zhang, et al., Dual nanoprecipitation and nanoscale chemical heterogeneity in a secondary hardening steel for ultrahigh strength and large uniform elongation, J. Mater. Sci. Technol., 185(2024), p. 245. doi: 10.1016/j.jmst.2023.10.048
[35]	M. Tanaka and C.S. Choi, The effects of carbon contents and M_s temperatures on the hardness of martensitic Fe–Ni–C alloys, Trans. Iron Steel Inst. Jpn., 12(1972), No. 1, p. 16. doi: 10.2355/isijinternational1966.12.16
[36]	Y.C. Li, W. Yan, J.D. Cotton, et al., A new 1.9GPa maraging stainless steel strengthened by multiple precipitating species, Mater. Des., 82(2015), p. 56. doi: 10.1016/j.matdes.2015.05.042
[37]	W.Q. Guo, B. Feng, Y. Yang, et al., Effect of laser scanning speed on the microstructure, phase transformation and mechanical property of NiTi alloys fabricated by LPBF, Mater. Des., 215(2022), art. No. 110460. doi: 10.1016/j.matdes.2022.110460
[38]	R. Esmaeilizadeh, A. Keshavarzkermani, U. Ali, et al., Customizing mechanical properties of additively manufactured Hastelloy X parts by adjusting laser scanning speed, J. Alloys Compd., 812(2020), art. No. 152097. doi: 10.1016/j.jallcom.2019.152097
[39]	A. Ullah, A. Ur Rehman, M.U. Salamci, F. Pıtır, and T.T. Liu, The influence of laser power and scanning speed on the microstructure and surface morphology of Cu₂O parts in SLM, Rapid Prototyping J., 28(2022), No. 9, p. 1796. doi: 10.1108/RPJ-12-2021-0342
[40]	M.M. Chen, R.H. Shi, Z.Z. Liu, et al., Phase-field simulation of lack-of-fusion defect and grain growth during laser powder bed fusion of Inconel 718, Int. J. Miner. Metall. Mater., 30(2023), No. 11, p. 2224. doi: 10.1007/s12613-023-2664-z
[41]	I. Hemmati, V. Ocelík, and J.T.M. De Hosson, Microstructural characterization of AISI 431 martensitic stainless steel laser-deposited coatings, J. Mater. Sci., 46(2011), No. 10, p. 3405. doi: 10.1007/s10853-010-5229-2
[42]	Y.Y. Chen, H.Y. Yue, and X.P. Wang, Microstructure, texture and tensile property as a function of scanning speed of Ti–47Al–2Cr–2Nb alloy fabricated by selective electron beam melting, Mater. Sci. Eng. A, 713(2018), p. 195. doi: 10.1016/j.msea.2017.12.020
[43]	Y.J. Liang, X. Cheng, and H.M. Wang, A new microsegregation model for rapid solidification multicomponent alloys and its application to single-crystal nickel-base superalloys of laser rapid directional solidification, Acta Mater., 118(2016), p. 17. doi: 10.1016/j.actamat.2016.07.008
[44]	K.Y. Wang, S.J. Lv, H.H. Wu, et al., Recent research progress on the phase-field model of microstructural evolution during metal solidification, Int. J. Miner. Metall. Mater., 30(2023), No. 11, p. 2095. doi: 10.1007/s12613-023-2710-x
[45]	J.Q. Zhang, M.J. Wang, L.H. Niu, et al., Effect of process parameters and heat treatment on the properties of stainless steel CX fabricated by selective laser melting, J. Alloys Compd., 877(2021), art. No. 160062. doi: 10.1016/j.jallcom.2021.160062
[46]	S. Afkhami, V. Javaheri, E. Dabiri, H. Piili, and T. Björk, Effects of manufacturing parameters, heat treatment, and machining on the physical and mechanical properties of 13Cr10Ni1.7Mo2Al0.4Mn0.4Si steel processed by laser powder bed fusion, Mater. Sci. Eng. A, 832(2022), art. No. 142402. doi: 10.1016/j.msea.2021.142402
[47]	D.C. Kong, C.F. Dong, X.Q. Ni, et al., Mechanical properties and corrosion behavior of selective laser melted 316L stainless steel after different heat treatment processes, J. Mater. Sci. Technol., 35(2019), No. 7, p. 1499. doi: 10.1016/j.jmst.2019.03.003
[48]	C. Chang, X.C. Yan, R. Bolot, et al., Influence of post-heat treatments on the mechanical properties of CX stainless steel fabricated by selective laser melting, J. Mater. Sci., 55(2020), No. 19, p. 8303. doi: 10.1007/s10853-020-04566-x
[49]	J. Su, M. Sanjari, A.S.H. Kabir, et al., Characteristics of magnesium AZ31 alloys subjected to high speed rolling, Mater. Sci. Eng. A, 636(2015), p. 582. doi: 10.1016/j.msea.2015.03.083
[50]	W. Zhao, H.L. Xiang, R.X. Yu, and G. Mou, Effects of laser scanning speed on the microstructure and mechanical properties of 2205 duplex stainless steel fabricated by selective laser melting, J. Manuf. Process., 94(2023), p. 1. doi: 10.1016/j.jmapro.2023.03.068
[51]	D.C. Kong, C.F. Dong, S.L. Wei, et al., About metastable cellular structure in additively manufactured austenitic stainless steels, Addit. Manuf., 38(2021), art. No. 101804.
[52]	Y.M. Wang, T. Voisin, J.T. McKeown, et al., Additively manufactured hierarchical stainless steels with high strength and ductility, Nat. Mater., 17(2018), p. 63. doi: 10.1038/nmat5021
[53]	K.G. Prashanth, S. Scudino, T. Maity, J. Das, and J. Eckert, Is the energy density a reliable parameter for materials synthesis by selective laser melting? Mater. Res. Lett., 5(2017), No. 6, p. 386. doi: 10.1080/21663831.2017.1299808
[54]	M. Yakout, M.A. Elbestawi, and S.C. Veldhuis, A study of thermal expansion coefficients and microstructure during selective laser melting of Invar 36 and stainless steel 316L, Addit. Manuf., 24(2018), p. 405.
[55]	J.L. Bartlett, F.M. Heim, Y.V. Murty, and X.D. Li, In situ defect detection in selective laser melting via full-field infrared thermography, Addit. Manuf., 24(2018), p. 595.
[56]	R. Cunningham, C. Zhao, N. Parab, et al., Keyhole threshold and morphology in laser melting revealed by ultrahigh-speed X-ray imaging, Science, 363(2019), No. 6429, p. 849. doi: 10.1126/science.aav4687
[57]	D.M. Li, X. Zhang, R.X. Qin, J.X. Xu, D.Y. Yue, and B.Z. Chen, Influence of processing parameters on AlSi10Mg lattice structure during selective laser melting: Manufacturing defects, thermal behavior and compression properties, Opt. Laser Technol., 161(2023), art. No. 109182. doi: 10.1016/j.optlastec.2023.109182
[58]	F.Z. Chu, E.L. Li, H.P. Shen, et al., Influence of powder size on defect generation in laser powder bed fusion of AlSi₁₀Mg alloy, J. Manuf. Process., 94(2023), p. 183. doi: 10.1016/j.jmapro.2023.03.046
[59]	J. Chao, D.G. Morris, M.A. Muñoz-Morris, and J.L. Gonzalez-Carrasco, The influence of some microstructural and test parameters on the tensile behaviour and the ductility of a mechanically-alloyed Fe–40Al alloy, Intermetallics, 9(2001), No. 4, p. 299. doi: 10.1016/S0966-9795(01)00005-X
[60]	Q.D. Yang, S. Yang, S.Y. Ma, et al. , In-situ X-ray computed tomography tensile tests and analysis of damage mechanism and mechanical properties in laser powder bed fused Invar 36 alloy, J. Mater. Sci. Technol., 175(2024), p. 29. doi: 10.1016/j.jmst.2023.08.014
[61]	J. Kwon, Y.T. Choi, E.S. Kim, et al., Effect of cell characteristics on mechanical properties of AlSi10Mg alloy fabricated by laser powder bed fusion, Mater. Sci. Eng. A, 901(2024), art. No. 146537. doi: 10.1016/j.msea.2024.146537
[62]	W.S. Tang, X.Q. Yang, C.B. Tian, and C. Gu, Effect of rotation speed on microstructure and mechanical anisotropy of Al-5083 alloy builds fabricated by friction extrusion additive manufacturing, Mater. Sci. Eng. A, 860(2022), art. No. 144237. doi: 10.1016/j.msea.2022.144237
[63]	S. Morito, H. Yoshida, T. Maki, and X. Huang, Effect of block size on the strength of lath martensite in low carbon steels, Mater. Sci. Eng. A, 438(2006), p. 237.
[64]	T.Q. Liu, Z.X. Cao, H. Wang, G.L. Wu, J.J. Jin, and W.Q. Cao, A new 2.4 GPa extra-high strength steel with good ductility and high toughness designed by synergistic strengthening of nano-particles and high-density dislocations, Scripta Mater., 178(2020), p. 285. doi: 10.1016/j.scriptamat.2019.11.045
[65]	J. Haubrich, J. Gussone, P. Barriobero-Vila, et al., The role of lattice defects, element partitioning and intrinsic heat effects on the microstructure in selective laser melted Ti–6Al–4V, Acta Mater., 167(2019), p. 136. doi: 10.1016/j.actamat.2019.01.039
[66]	M.C. Niu, G. Zhou, W. Wang, M.B. Shahzad, Y.Y. Shan, and K. Yang, Precipitate evolution and strengthening behavior during aging process in a 2.5 GPa grade maraging steel, Acta Mater., 179(2019), p. 296. doi: 10.1016/j.actamat.2019.08.042
[67]	E.I. Galindo-Nava and P.E.J. Rivera-Díaz-del-Castillo, A model for the microstructure behaviour and strength evolution in lath martensite, Acta Mater., 98(2015), p. 81. doi: 10.1016/j.actamat.2015.07.018
[68]	V.K. Vasudevan, S.J. Kim, and C.M. Wayman, Precipitation reactions and strengthening behavior in 18 Wt Pct nickel maraging steels, Metall. Trans. A, 21(1990), No. 10, p. 2655. doi: 10.1007/BF02646061
[69]	R.L. Fleischer, Substitutional solution hardening, Acta Metall., 11(1963), No. 3, p. 203. doi: 10.1016/0001-6160(63)90213-X
[70]	R. Labusch, A statistical theory of solid solution hardening, Phys. Status Solidi B., 41(1970), No. 2, p. 659. doi: 10.1002/pssb.19700410221
[71]	E.I. Galindo-Nava and P.E.J. Rivera-Díaz-del-Castillo, Understanding the factors controlling the hardness in martensitic steels, Scripta Mater., 110(2016), p. 96. doi: 10.1016/j.scriptamat.2015.08.010
[72]	G. Ghosh and G.B. Olson, Kinetics of F.C.C. → B.C.C. heterogeneous martensitic nucleation—I. The critical driving force for athermal nucleation, Acta Metall. Mater., 42(1994), No. 10, p. 3361. doi: 10.1016/0956-7151(94)90468-5
[73]	P. Peng, K.S. Wang, W. Wang, et al., Relationship between microstructure and mechanical properties of friction stir processed AISI 316L steel produced by selective laser melting, Mater. Charact., 163(2020), art. No. 110283. doi: 10.1016/j.matchar.2020.110283
[74]	H.H. Jin, E. Ko, J. Kwon, S.S. Hwang, and C. Shin, Evaluation of critical resolved shear strength and deformation mode in proton-irradiated austenitic stainless steel using micro-compression tests, J. Nucl. Mater., 470(2016), p. 155. doi: 10.1016/j.jnucmat.2015.12.029
[75]	B.Q. Han and D.C. Dunand, Creep of magnesium strengthened with high volume fractions of yttria dispersoids, Mater. Sci. Eng. A, 300(2001), No. 1-2, p. 235. doi: 10.1016/S0921-5093(00)01781-0
[76]	Y. Xiang, Modeling dislocations at different scales, Commun. Comput. Phys., 1(2006), No. 3, p. 383.
[77]	B. Kim, E. Boucard, T. Sourmail, D. San Martín, N. Gey, and P.E.J. Rivera-Díaz-del-Castillo, The influence of silicon in tempered martensite: Understanding the microstructure–properties relationship in 0.5–0.6wt.% C steels, Acta Mater., 68(2014), p. 169. doi: 10.1016/j.actamat.2014.01.039