AccScience Publishing / MSAM / Online First / DOI: 10.36922/MSAM026240055
Submit to MSAM
Cite this article
4
Download
68
Views
Related Info Links
Google Scholar
More by Authors Links
Mingjie Zhao
Journal Browser
Volume | Year
Issue
Search
Forthcoming Issue
Current Issue
View All
News and Announcements
View All
ORIGINAL RESEARCH ARTICLE

Uncovering the role of heterogeneous microstructure in the mechanical anisotropy of ultra-high-strength steel fabricated by directed energy deposition–arc

Junyang Tu1 ,  Mingjie Zhao1* ,  Lihong Jiang1 ,  You Li1 ,  An Lu1 ,  Zhenghua Guo1
Show Less
1 Jiangxi Provincial Key Laboratory of Extreme Manufacturing Technology for High-end Equipment, School of Materials Science and Engineering, Nanchang Hangkong University, Nanchang, Jiangxi, China
MSAM, 026240055 https://doi.org/10.36922/MSAM026240055
Received: 9 June 2026 | Revised: 3 July 2026 | Accepted: 8 July 2026 | Published online: 21 July 2026
© 2026 by the Author(s). This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution 4.0 International License ( https://creativecommons.org/licenses/by/4.0/ )
Download PDF
XML
Cite
Abstract

The anisotropic properties of components produced by directed energy deposition–arc (DED-Arc) markedly limit their use in engineering. Thus, it is crucial to elucidate the mechanism that regulates this anisotropic phenomenon in DED-Arc components to ensure the reliable application of this technology in high-performance components. In this study, 300M steel was fabricated by DED-Arc with controlled interlayer temperature, and a critical phenomenon was observed. At an interlayer temperature of 200 °C, the strength was isotropic, while the ductility exhibited a certain degree of anisotropy. When the interlayer temperature increased above the martensite start temperature to 300 °C, a unique anisotropy in mechanical properties emerged. The vertical specimens exhibited higher ultimate tensile strength and elongation but lower yield strength than the horizontal specimens. At an interlayer temperature of 200 °C, the microstructure was relatively uniform and consisted entirely of tempered martensite. The plastic anisotropy mainly originated from directional grain growth. At an interlayer temperature of 300 °C, the microstructure evolved into a heterogeneous structure consisting of alternating soft and hard zones, caused by the uneven distribution of soft phases (tempered martensite and needle‑like bainite) and hard phases (untempered martensite). In this case, the spatial arrangement of the heterogeneous structure governed the anisotropy. Under horizontal tension, the soft and hard zones are alternately stacked perpendicular to the tensile direction, and the deformation compatibility was constrained by the hard zones, resulting in higher yield strength but lower ductility. Under vertical tension, the soft and hard zones are stacked parallel to the tensile direction, offering better deformation compatibility. Moreover, the Orowan strengthening effect induced by the interlayer regions was more pronounced, leading to a higher ultimate tensile strength than that of the horizontal specimens. This study elucidates the microscale mechanism of heterogeneous structure formation upon exceeding the martensite start temperature, thereby producing this unique anisotropy.

Graphical abstract
Keywords
Ultra-high-strength steel
Directed energy deposition
Interlayer temperature
Heterogeneous structure
Anisotropy
Funding
This work was supported by the National Natural Science Foundation of China (Grant No. 52564058 and 52305373) and the Jiangxi Provincial Natural Science Foundation (Grant No. 20252BAC240335).
Conflict of interest
The authors declare they have no competing interests.
References
  1. Bai Y, Zhang S, Yan Q, Zhao C, Zhan J. Enhanced strength of A131 steel via heterostructures induced by laser-directed energy deposition. Mater Sci Add Manuf. 2025;4(3):025220038. doi: 10.36922/MSAM025220038
  2. Zhao M, Jiang L, Li C, et al. Flow characteristics and hot workability of a typical low-alloy high-strength steel during multi-pass deformation. Int J Miner Metall Mater. 2024;31(2):323-336. doi: 10.1007/s12613-023-2736-0
  3. Zhao M, Li C, Jiang L, et al. Hot workability of a typical ultrahigh strength steel during the isothermal forging process. Met Mater Int. 2023;30(4):1055-1071. doi: 10.1007/s12540-023-01560-1
  4. Li K, Yang TB, Gong N, et al. Additive manufacturing of ultra-high strength steels: A review. J Alloys Compd. 2023;965:171390. doi: 10.1016/j.jallcom.2023.171390
  5. Sandua X, Arbizu E, Rodríguez A, Veiga F, Martín MÁ, Rivero PJ. Influence of laser power and hatch spacing on the mechanical properties of AlSi10Mg processed by selective laser melting. Mater Sci Add Manuf. 2026;5(2):026040008. doi: 10.36922/MSAM026040008
  6. Gain S, Veeman D. A review on advances and challenges in wire arc additive manufacturing: Process parameters, microstructural evolution and material performance across alloys. J Alloys Compd. 2025;1029:180735. doi: 10.1016/j.jallcom.2025.180735
  7. Yang L, Yi H, Jia L, Zhang W, Cao H. Achieving collaborative improvement of strength and plasticity of wire arc additive manufactured Ti-6Al-4V titanium alloy via ultrasonic vibration and heat treatment. Appl Mater Today. 2026;48:103040. doi: 10.1016/j.apmt.2025.103040
  8. Zhang H, Li R, Liu J, et al. State‑of‑art review on the process‑structure‑properties‑performance linkage in wire arc additive manufacturing. Virtual Phys Prototyp. 2024;19(1). doi: 10.1080/17452759.2024.2390495
  9. Wang X, Deng J, Zhao R, Shen L, Wang Z. Compressive response and energy absorption of 3D-printed cellular structures: advances and challenges. Virtual Phys Prototyp. 2026;21(1). doi: 10.1080/17452759.2026.2638085
  10. Guo Z, Lu A, Zhao M, Jiang L, Wang G. Effects of bainite transformation on mechanical properties of 300 M ultra-high strength steel fabricated by power plasma arc additive manufacturing. Materialia. 2025;44:102586. doi: 10.1016/j.mtla.2025.102586
  11. Zhang J, Fan J, Xu J, ang D, Peng Y, Wang K. The effect of heat input on the microstructure and mechanical properties of 18Ni 300 maraging steel fabricated by arc directed energy deposition. Mater Sci Eng A. 2023;884:145545. doi: 10.1016/j.msea.2023.145545
  12. Lyu Z, Sato YS, Xu W, et al. Simultaneous enhancements of strength and ductility of wire arc additive manufactured 17‑4PH steel via intrinsic heat treatment. J Mater Process Technol. 2023;321:118149. doi: 10.1016/j.jmatprotec.2023.118149
  13. Xiong Y, Wen D, Zheng Z, Sun C, Xie J, Li J. Effect of heat treatment on microstructure and mechanical properties of directed energy deposition-Arc 300M steel. Mater Charact. 2023;198:112756. doi: 10.1016/j.matchar.2023.112756
  14. Li Y, Xiong Y, Zhao M, et al. Synergistic enhancement of strength and ductility for plasma arc additive manufactured ultrahigh strength steel by a novel heat treatment. Arch Civ Mech Eng. 2026;26(3). doi: 10.1007/s43452-026-01501-w
  15. Dekis M, Tawfik M, Egiza M, Dewidar M. Challenges and developments in wire arc additive manufacturing of steel: a review. Results Eng. 2025;26:104657. doi: 10.1016/j.rineng.2025.104657
  16. Wang C, Lou D, Duan Z,  Rong J, Xu B. Structural topology optimization considering multi‑source anisotropic failure strength from printing space and material locality. Comput Methods Appl Mech Eng. 2025;446:118309. doi: 10.1016/j.cma.2025.118309
  17. Shi Q, Wang J, Xu X, Liu Y, Wen Z, Yue Z. Temperature‑dependent tensile anisotropic behavior of WAAM‑TC4 dual‑phase titanium alloy: Microstructural evolution, deformation mechanisms, and fracture characteristics. Mater Sci Eng A. 2025;943:148748. doi: 10.1016/j.msea.2025.148748
  18. Blinn B, Hassel T, Viebranz VF, Beck T, Maier HJ. Influence of the grain orientation and δ‑ferrite on the cyclic deformation behavior of an austenitic CrNi steel manufactured by wire and arc additive manufacturing. Mater Sci Eng A. 2023;870:144612. doi: 10.1016/j.msea.2023.144612
  19. Akbarzadeh Chiniforoush E, Zargari HH, Jandaghi MR, Moverare J, Warsi R, Gür CH. A sustainable strategy for wire arc additive manufacturing of high‑performance duplex stainless steel: Microstructural refinement and mechanical anisotropy reduction. Mater Sci Eng A. 2025;943:148785. doi: 10.1016/j.msea.2025.148785
  20. Palmeira Belotti L, van Dommelen JAW, Geers MGD, Ya W, Hoefnagels JPM. Influence of the printing strategy on the microstructure and mechanical properties of thick-walled wire arc additive manufactured stainless steels. J Mater Process Tech. 2024;324:118275. doi: 10.1016/j.jmatprotec.2023.118275
  21. Sun L, Jiang F, Huang R, Yuan D, Guo C, Wang J. Anisotropic mechanical properties and deformation behavior of low‑carbon high‑strength steel component fabricated by wire and arc additive manufacturing. Mater Sci Eng A. 2020;787:139514. doi: 10.1016/j.msea.2020.139514
  22. Chen W, Cao H, Zhu L. Heterogeneous microstructure and anisotropic mechanical properties of reduced activation ferritic/martensitic steel fabricated by wire arc additive manufacturing. Nucl Mater Energy. 2022;33:101261. doi: 10.1016/j.nme.2022.101261
  23. Tu Y, Zheng D, Li Z, Zhang C, Gong X. Microstructure and mechanical properties of Mg‑12Gd‑3Y‑4Zr magnesium alloy with layered heterogeneous microstructure fabricated by wire arc additive manufacturing. J Alloys Compd. 2025;1037:182210. doi: 10.1016/j.jallcom.2025.182210
  24. Lyu Z, Sato YS, Tokita S, Zhao Y, Jia J, Wu A. Microstructural distribution and anisotropic tensile behavior in a 2Cr13 martensitic stainless steel thin wall fabricated by wire arc additive manufacturing. Mater Today Commun. 2021;29:102870. doi: 10.1016/j.mtcomm.2021.102870
  25. Zhai W, Wu N, Zhou W. Effect of interpass temperature on wire arc additive manufacturing using high-strength metal-cored wire. Metals. 2022;12(2):212. doi: 10.3390/met12020212
  26. Xiong Y, Wen D, Zheng Z, Li J. Effect of interlayer temperature on microstructure evolution and mechanical performance of wire arc additive manufactured 300M steel. Mater Sci Eng A. 2022;831:142351. doi: 10.1016/j.msea.2021.142351
  27. Wei S, Wang P, Zhang L, Ramamurty U. Grain morphologies in additively manufactured alloys: From solidification fundamentals to advanced microstructure control. J Mater Sci Technol. 2025;235:133-145. doi: 10.1016/j.jmst.2025.02.033
  28. Gao P, Fan J, Cai B, et al. Effect of interlayer temperature on the microstructure and mechanical properties of new Co-Free maraging steel fabricated by arc-based directed energy deposition. Mater Charact. 2025;222:114851. doi: 10.1016/j.matchar.2025.114851
  29. Salahi S, Nemani AV, Ghaffari M,  Lunde J, Nasiri A. On microstructure, crystallographic orientation, and corrosion properties of wire arc additive manufactured 420 martensitic stainless steel: Effect of the inter-layer temperature. Addit Manuf. 2021;46:102157. doi: 10.1016/j.addma.2021.102157
  30. Liu F, Lin X, Song M, et al. Effect of tempering temperature on microstructure and mechanical properties of laser solid formed 300M steel. J Alloys Compd. 2016;689:225-232. doi: 10.1016/j.jallcom.2016.07.276
  31. Chen R, Zheng Z, Li N, Li J, Feng F. In-situ investigation of phase transformation behaviors of 300M steel in continuous cooling process. Mater Charact. 2018;144:400-410. doi: 10.1016/j.matchar.2018.07.034
  32. Franceschi M, Morales‑Rivas L, Cordova‑Tapia E, Jimenez JA, Dabalà M, Garcia-Mateo C. Study of bainite and martensite tempering in a medium C high Si steel. microstructural disparities and equilibrium convergence. J Mater Res Technol. 2024;32:2931-2944. doi: 10.1016/j.jmrt.2024.08.141
  33. Hu Z, Hua L, Ni M, Ji F, Qin X. Microstructure and mechanical properties of directed energy deposition-arc/wire bimetallic hierarchical structures of hot-working tool steel and martensitic stainless steel. Addit Manuf. 2023;67:103495. doi: 10.1016/j.addma.2023.103495
  34. Li M, Zhang W, Zhou Z, et al. Effect of the interlayer temperature on microstructure and mechanical behavior of the high-strength low-alloy steel manufactured by the wire arc additive manufacturing. Mater Today Commun. 2025;46:112845. doi: 10.1016/j.mtcomm.2025.112845
  35. Wang X, Li J, Huang S, et al. Elimination mechanism of the anisotropy of additively manufactured alloys in high temperature mechanical properties by HG-S2A treatment. J Alloys Compd. 2025;1044:184377. doi: 10.1016/j.jallcom.2025.184377
  36. Sun J, Ma N, Deng D, Dilger K. Generation mechanism and distribution characteristics of residual stresses in wire-arc additively manufactured ultra-high strength steel components. J Mater Res Technol. 2025;38:6244-6259. doi: 10.1016/j.jmrt.2025.09.059
  37. Turnali A, Kibaroglu D, Evers N, et al. Segregation-guided alloy design via tailored solidification behavior. Mater Today Adv. 2025;25:100549. doi: 10.1016/j.mtadv.2024.100549
  38. Feng L, Gao J, Liu F, Huang C, Zheng Y. Effect of grain orientation on microstructure and mechanical properties of laser welded joint of additive manufactured 300M steel. Mater Today Commun. 2023;35:105497. doi: 10.1016/j.mtcomm.2023.105497
  39. Jing G, Huang W, Yang H, Wang Z. Microstructural evolution and mechanical properties of 300M steel produced by low and high power selective laser melting. J Mater Sci Technol. 2020;48:44-56. doi: 10.1016/j.jmst.2019.12.020
  40. Mishra NK, Ajay V, Nakrani J, Shrivastava A. Influence of dwell time on mechanical and microstructural anisotropy of additively manufactured SS 316 L: Experimental and numerical investigation. J Manuf Process. 2025;145:600-615. doi: 10.1016/j.jmapro.2025.04.072
  41. Liu X, Liu ZT, Zhang SY, et al. Isotropic high strength Al-Mg-Si-Zn-Cu alloy fabricated by wire-arc additive manufacturing via Ti nanoparticles addition. Mater Charact. 2026;233:116148. doi: 10.1016/j.matchar.2026.116148
  42. Palmeira Belotti LP, van Dommelen JAW, Geers MGD, Goulas C, Ya W, Hoefnagels JPM. Microstructural characterisation of thick‑walled wire arc additively manufactured stainless steel. J Mater Process Technol. 2022;299:117373. doi: 10.1016/j.jmatprotec.2021.117373
  43. Tian C, Ponge D, Christiansen L, Kirchlechner C. On the mechanical heterogeneity in dual phase steel grades: Activation of slip systems and deformation of martensite in DP800. Acta Mater. 2020;183:274-284. doi: 10.1016/j.actamat.2019.11.002
  44. Isavand S, Rao PS, Bondarev A, et al. Integrating micropillar compression testing and crystal plasticity modelling to unravel slip system activity and deformation mechanisms in P91 steel. Mater Sci Eng A. 2025;942:148659. doi: 10.1016/j.msea.2025.148659
  45. Ng KS, Ngan AHW. Breakdown of Schmid’s law in micropillars. Scr Mater. 2008;59(7):796-799. doi: 10.1016/j.scriptamat.2008.06.019
  46. Shen JH, Li YL, Wei Q. Statistic derivation of taylor factors for polycrystalline metals with application to pure magnesium. Mater Sci Eng A. 2013;582:270-275. doi: 10.1016/j.msea.2013.06.025
  47. Sarkar A, Sanyal S, Bandyopadhyay TK,  Mandal S. Implications of microstructure, taylor factor distribution and texture on tensile properties in a Ti-added Fe-Mn-Al-Si-C steel. Mater Sci Eng A. 2019;767:138402. doi: 10.1016/j.msea.2019.138402
  48. Jia N, Cong ZH, Sun X, et al. An in situ high-energy X-ray diffraction study of micromechanical behavior of multiple phases in advanced high-strength steels. Acta Mater. 2009;57(13):3965-3977. doi: 10.1016/j.actamat.2009.05.002
  49. Wronski S, Wierzbanowski K, Jędrychowski M, et al. Microstructure evolution of titanium after tensile test. Mater Sci Eng A. 2016;656:1-11. doi: 10.1016/j.msea.2015.12.041
  50. Gao P, Jing G, Lan X, et al. Effect of heat treatment on microstructure and mechanical properties of Fe–Cr–Ni–Co–Mo maraging stainless steel produced by selective laser melting. Mater Sci Eng A. 2021;814:141149. doi: 10.1016/j.msea.2021.141149
  51. Yin S, Chen C, Yan X, et al. The influence of aging temperature and aging time on the mechanical and tribological properties of selective laser melted maraging 18Ni-300 steel. Addit Manuf. 2018;22:592-600. doi: 10.1016/j.addma.2018.06.005
  52. Otani Y, Takata N, Suzuki A, Kobashi M, Kato M. Microstructural origin of anisotropic tensile ductility of Al-Si alloy manufactured by laser powder bed fusion. Scr Mater. 2023;226:115259. doi: 10.1016/j.scriptamat.2022.115259
  53. Jing G, Wang Z. Influence of molten pool mode on microstructure and mechanical properties of heterogeneously tempered 300M steel by selective laser melting. J Mater Process Technol. 2021;296:117188. doi: 10.1016/j.jmatprotec.2021.117188
  54. Wang H, Zhang J, Liu Y, et al. Achieving high strength and low modulus titanium alloy with non-uniform multiscale heterogeneous microstructures. J Mater Sci Technol. 2026;264:151-162. doi: 10.1016/j.jmst.2025.11.026
  55. Jing G, Wang Z. Defects, densification mechanism and mechanical properties of 300M steel deposited by high power selective laser melting. Addit Manuf. 2021;38:101831. doi: 10.1016/j.addma.2020.101831
  56. Ma K, Wen H, Hu T, et al. Mechanical behavior and strengthening mechanisms in ultrafine grain precipitation-strengthened aluminum alloy. Acta Mater. 2014;62:141-155. doi: 10.1016/j.actamat.2013.09.042
  57. Yu Q, Zhang Y, Jia Z, Huang L, Geng L. Synergistic effect of aluminum distribution and in-situ annealing on layered microstructure formation: Microstructural evolution and mechanical anisotropy mechanisms in EBM-fabricated Ti-48Al-2Cr-2Nb. Mater Sci Eng A. 2026;949:149383. doi: 10.1016/j.msea.2025.149383
Share
Back to top
Materials Science in Additive Manufacturing, Electronic ISSN: 2810-9635 Published by AccScience Publishing
We use cookies on our website to ensure you get the best experience.
Read more about our cookies here
Accept