Basic artificial intelligence for metallurgical design of acicular ferrite in weld metal

Krishnaswamy Sampath

doi:10.59400/mtr3805

Basic artificial intelligence for metallurgical design of acicular ferrite in weld metal

Krishnaswamy Sampath
Independent Researcher, Santa Clara, CA 95054, USA

Article ID: 3805

Keywords: electrode evaluation, shielded metal arc welding, database, Ti-B-Al-N-O micro-alloy additions, acicular ferrite, JWES-ANN tool, New Ar3 transformation temperature

Abstract

Demand-critical applications require high strength steel (HSS) weldments with a significant spread between yield strength (YS) and ultimate tensile strength (UTS). Predominantly acicular ferrite (AF) microstructure in weld metal (WM) of a Fe-C-Mn-Ni based system is suitable for joining HSSs for demand-critical applications. Controlling carbon content in WM below 0.10 wt-%, actual or calculated transformation-start (T_S) temperature between 630 °C and 730 °C and weld cooling rate (CR) is critical in generating a high-performance AF microstructure. The Japan Welding Engineering Society (JWES) offers an artificial neural network (ANN) template at its website which is helpful in manipulating the addition of 16 elements in WM, each within a restricted range. This manipulation allows one to lower the T_28J/°C Charpy V-notch (CVN) test temperature of WM below −80 °C for achieving 28 Joules impact energy. Secondly, a New A_r3 equation obtained using regression analysis through Machine Learning, enables manipulation of 14 elements (except P and S) in WM (all in wt-%) and weld CR (in °C/s) in achieving a predominantly AF microstructure in WM. Dilatometric analysis of selected WMs with Ti-B-Al-N-O content and limited N content below 85 ppm (0.0085 wt-%) showed that these two supplementary approaches can achieve a nearly “balanced” Ti-B-Al-N-O micro-alloying addition in WM. The above two tools allow welding engineers to use basic Artificial Intelligence (AI) system in evaluating or recognizing welding electrodes and related WMs that ensure adequate spread between YS and UTS, and a predictive T_28J/°C test temperature below −80 °C for demand-critical applications.

Published

2025-09-27

How to Cite

Sampath, K. (2025). Basic artificial intelligence for metallurgical design of acicular ferrite in weld metal. Materials Technology Reports, 3(2). https://doi.org/10.59400/mtr3805

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Issue

Vol. 3 No. 2 (2025)

Section

Review

This work is licensed under a Creative Commons Attribution 4.0 International License.

References

[1]American Welding Society (AWS). Structural Welding Code—Seismic Supplement. American Welding Society; 2021.

[2]Schank JF, Ip C, Lacroix FW, et al. Learning from Experience, Volume II: Lessons from the U.S. Navy's Ohio, Seawolf, and Virginia Submarine Programs. RAND Corporation; 2011.

[3]Ohaeri EG, Szpunar JA. An overview on pipeline steel development for cold climate applications. Journal of Pipeline Science and Engineering. 2022; 2(1): 1–17. doi: 10.1016/j.jpse.2022.01.003

[4]Farrar RA, Harrison PL. Acicular ferrite in carbon-manganese weld metals: An overview. Journal of Materials Science. 1987; 22(11): 3812–3820. doi: 10.1007/BF01133327

[5]Babu SS. The mechanism of acicular ferrite in weld deposits. Current Opinion in Solid State and Materials Science. 2004; 8(3–4): 267–278. doi: 10.1016/j.cossms.2004.10.001

[6]Fox AG, Evans GM. A comparative study of the non-metallic inclusions in C-Mn steel weld metals containing titanium or aluminium. In: DebRoy T, David SA, DuPont JN, et al. (editors). Trends in Welding Research. ASM International; 2013. pp. 623–630.

[7]Costin WL, Lavigne O, Kotousov A. A study on the relationship between microstructure and mechanical properties of acicular ferrite and upper bainite. Materials Science and Engineering: A. 2016; 663: 193–203.

[8]Loder D, Michelic SK, Bernhard C. Acicular Ferrite Formation and Its Influencing Factors—A Review. Journal of Materials Science Research. 2016; 6(1): 24. doi: 10.5539/jmsr.v6n1p24

[9]Kang Y, Jeong S, Kang JH, et al. Factors Affecting the Inclusion Potency for Acicular Ferrite Nucleation in High-Strength Steel Welds. Metallurgical and Materials Transactions A. 2016; 47(6): 2842–2854. doi: 10.1007/s11661-016-3456-0

[10]Vezzù S, Scappin M, Boaretto D, et al. On the Effect of Slight Variations of Si, Mn, and Ti on Inclusions Properties, Microstructure, and Mechanical Properties of YS460 C-Mn Steel Welds. Metallography, Microstructure, and Analysis. 2019; 8(3): 292–306. doi: 10.1007/s13632-019-00536-1

[11]Ito Y, Nakanishi M, Komizo Y. Effects of oxygen on low carbon steel weld metal. Metal Construction. 1982; 14(9): 472–478.

[12]Consumables for welding of (very) high strength steels-mechanical properties of weldments in as-welded and stress-relieved applications. Available online: https://www.phase-trans.msm.cam.ac.uk/2005/LINK/90.pdf (accessed on 1 June 2025).

[13]Miettinen J, Koskenniska S, Somani M, et al. Optimization of the CCT Curves for Steels Containing Al, Cu and B. Metallurgical and Materials Transactions B. 2021; 52(3): 1640–1663. doi: 10.1007/s11663-021-02130-9

[14]Yamada T, Terasaki H, Komizo Y. Relation between Inclusion Surface and Acicular Ferrite in Low Carbon Low Alloy Steel Weld. ISIJ International. 2009; 49(7): 1059–1062. doi: 10.2355/isijinternational.49.1059

[15]Takada A, Terasaki H, Komizo Y. Effect of aluminium content on acicular ferrite formation in low carbon steel weld metals. Science and Technology of Welding and Joining. 2013; 18(2): 91–97. doi: 10.1179/1362171812Y.0000000086

[16]Takada A, Komizo YI, Terasaki H, et al. Crystallographic analysis for acicular ferrite formation in low carbon steel weld metals. Welding International. 2015; 29(4): 254–261. doi: 10.1080/09507116.2014.921042

[17]Yurioka N, Suzuki H, Ohshita S, et al. Determination of necessary preheating temperature in steel welding. Welding Journal. 1983; 2(6): 147–153.

[18]Evans GM. Database—Weld metal composition and properties. 2015; doi: 10.13140/RG.2.1.3628.1764

[19]Charpy transition temp of all-weld-metal. Available online: https://www-it.jwes.or.jp/weld_simulator/en/cal6.jsp (accessed on 1 July 2025).

[20]Ilman MN, Cochrane RC, Evans GM. Effect of Nitrogen and Boron on the Development of Acicular Ferrite iN Reheated C-Mn-Ti Steel Weld Metals. Welding in the World. 2012; 56(11–12): 41–50. doi: 10.1007/BF03321394

[21]Ilman MN, Cochrane RC, Evans GM. Effect of titanium and nitrogen on the transformation characteristics of acicular ferrite in reheated C–Mn steel weld metals. Welding in the World. 2014; 58(1): 1–10. doi: 10.1007/s40194-013-0091-x

[22]Ilman MN, Cochrane RC, Evans GM. The development of acicular ferrite in reheated Ti–B–Al–N-type steel weld metals containing various levels of aluminium and nitrogen. Welding in the World. 2015; 59(4): 565–575. doi: 10.1007/s40194-015-0231-6

[23]Evans GM, Bailey N. Metallurgy of Basic Weld Metal. Elsevier; 1997.

[24]Sampath K. Analysis of a High-Strength Steel SMAW Database. Welding Journal. 2021; 100(12): 410–420. doi: 10.29391/2022.101.036

[25]Sampath K, Varadarajan R. High strength steel weld metal properties: metallurgical criteria and computational tools. Welding in the World. 2023; 67(9): 2081–2105. doi: 10.1007/s40194-023-01551-1

[26]Bhadeshia HKDH. Frontiers in the Modelling of Steel Weld Deposits. Journal of The Japan Welding Society. 2007; 76(2): 102–108. doi: 10.2207/jjws.76.102

[27]Dearden J, O’Neill H. A guide to the selection and welding of low alloy structural steel. Transactions of the Institute of Welding. 1940; 3: 203–214.

[28]Ito Y, Bessyo K. Weldability Formula of High Strength Steels Related to Heat Affected Zone Cracking. International Institute of Welding; 1968.

[29]Sampath K. An Understanding of HSLA-65 Plate Steels. Journal of Materials Engineering and Performance. 2006; 15(1): 32–40. doi: 10.1361/105994906X83439

[30]Sugiyama M, Sawa G, Hata K, et al. Heterogeneous microstructure of low-carbon lath martensite with continuous yielding behavior in Fe-C-Mn alloys. IOP Conference Series: Materials Science and Engineering. 2019; 580(1): 012045. doi: 10.1088/1757-899X/580/1/012045

[31]Jorge JCF, Souza LFG, Mendes MC, et al. Microstructure characterization and its relationship with impact toughness of C–Mn and high strength low alloy steel weld metals—A review. Journal of Materials Research and Technology. 2021; 10: 471–501. doi: 10.1016/j.jmrt.2020.12.006

[32]Sampath K. Three Essential Steps in Metallurgical Design of Solid Wire Electrodes for High Strength Steels. Aspects in Mining & Mineral Science. 2025; 14(1): 1694–1699.

[33]Bosansky J, Evans GM. Relationships between the properties of weld metals microalloyed with V and Nb, their structure and substructure. Welding International. 1992; 6(12): 997–1002. doi: 10.1080/09507119209548332

[34]Sampath K. Constraints-based modeling enables successful development of a welding electrode specification for critical navy applications. Welding Journal. 2005; 84(8): 131–138.

[35]MIL-E-23765/2E, Military Specification: Electrodes and Rods—Welding, Bare, Solid, or Alloy Cored; and Fluxes, Low Alloy Steel (22 APR 1994). Available online: https://everyspec.com/MIL-SPECS/MIL-SPECS-MIL-E/MIL-E-23765-2E_12865/ (accessed on 1 July 2025).

[36]American Welding Society (AWS). Specification for Low-Alloy Steel Electrodes and Rods for Gas Shielded Arc Welding. American Welding Society; 2022.

[37]American Welding Society (AWS). Specification for Low-Alloy Steel Electrodes for Shielded Metal Arc Welding. American Welding Society; 2022.

[38]Bhadeshia HKDH, MacKay DJC, Svensson LE. Impact toughness of C–Mn steel arc welds–Bayesian neural network analysis. Materials Science and Technology. 1995; 11(10): 1046–1051.

[39]Kim JH, Jung CJ, Park YI, et al. Development of Closed-Form Equations for Estimating Mechanical Properties of Weld Metals according to Chemical Composition. Metals. 2022; 12(3): 528. doi: 10.3390/met12030528

[40]Yoon T, Park YI, Kim J, et al. Inverse Neural Network Approach for Optimizing Chemical Composition in Shielded Metal Arc Weld Metals. Materials. 2025; 18(11): 2592. doi: 10.3390/ma18112592

[41]Sampath K. Metallurgical Design Rules for High-Strength Steel Weld Metals. Welding Journal. 2022; 101(5): 123–143. doi: 10.29391/2022.101.010

[42]Svensson LE, Gretoft DB. Microstructure and Impact Toughness of C-Mn Weld Metals. Welding Journal. 1990; 69(12): 454–461.

[43]Zhang Z, Farrar RA. Influence of Mn and Ni on the Microstructure and Toughness of C-Mn-Ni Weld Metals. Welding Journal. 1997; 76(5): 184–196.

[44]Johnson MQ, Evans GM, Edwards GR. The Influence of Titanium Additions and Interpass Temperature on the Microstructures and Mechanical Properties of High Strength SMA Weld Metals. ISIJ International. 1995; 35(10): 1222–1231. doi: 10.2355/isijinternational.35.1222

[45]Oh DW, Olson DL, Frost RH. The influence of boron and titanium on low-carbon steel weld metal. Welding Journal. 1990; 69(4): 151–158.

[46]Sampath K. Selective Analysis of a High-Strength Steel Shielded Metal Arc Weld Metal Database. Aspects in Mining & Mineral Science. 2024; 12(4). doi: 10.31031/AMMS.2024.12.000795

[47]Varadarajan R, Sampath K. Application of Machine Learning to Regression Analysis of a Large SMA Weld Metal Database. Welding Journal. 2023; 102(3): 31–52. doi: 10.29391/2023.102.004

[48]Schroeder N, Rhode M, Kannengiesser T. Influence of microalloying on precipitation behavior and notch impact toughness of welded high-strength structural steels. Welding in the World. 2024; 68(10): 2647–2659. doi: 10.1007/s40194-024-01827-0

[49]Schroeder N, Rhode M, Kannengiesser T, et al. Effect of Ti microalloying on the local strain behavior of cross-weld tensile samples determined by digital image correlation. Welding in the World. 2025;. doi: 10.1007/s40194-025-02185-1

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