PSI - Issue 76

Xabat Orue et al. / Procedia Structural Integrity 76 (2026) 3–10 Murakami ’ s √ parameter enables a proper characterization of the equivalent defect size. The presented work sheds light on the applicability of K-T diagrams of Ti-6Al-4V manufactured by DED-LB/CW for its life predictions based on FCG. Future research lines are undergoing in this field by the authors of this work, including short crack regime for a better fatigue assessment. Acknowledgements The authors wish to acknowledge the fundings received by CDTI in the framework of CERVERA through the SURF-ERA PLUS project with reference EXP 00163512 / CER-20231008. References [1] R.M. Mahamood, Laser Metal Deposition Process of Metals, Alloys, and Composite Materials, 1st ed., Springer, Manchester, 2018. http://www.springer.com/series/4604. [2] X. Orue, J.L. Iñarrairaegi, E. Tabares, M. Abasolo, C. Soriano, I. Quintana, Comparative analysis of Direct Energy Deposition parameters for Ti-6Al-4V using laser beam and coaxial wire (DED-LB/CW), in: Procedia CIRP, Fürth, 2024: pp. 205 – 209. https://doi.org/10.1016/j.procir.2024.08.100. [3] J. Flores, I. Cabanes, A. Gutierrez, K.L. de Calle, O. Gonzalo, E. Portillo, An innovative smart monitoring system for DED-LB/MW process stability based on machine learning techniques, International Journal of Advanced Manufacturing Technology (2025). https://doi.org/10.1007/s00170-025-15134-5. [4] H. Kitagawa, Applicability of Fracture Mechanics to Very Small Cracks or the Cracks in the Early Stage, in: 2nd ICM, 1976: pp. 627 – 631. [5] M.H. El Haddad, K.N. Smith, T.H. Topper, Fatigue Crack Propagation of Short Cracks, J Eng Mater Technol 101 (1979) 42 – 46. https://doi.org/10.1115/1.3443647. [6] Y. Murakami, Metal Fatigue: Effects of Small Defects and Nonmetallic Inclusions, 2nd ed., Elsevier, 2019. https://doi.org/10.1016/b978-0-12-813876-2.00001-7. [7] K. Walker, The Effect of Stress Ratio During Crack Propagation and Fatigue for 2024-T3 and 7075-T6 Aluminum, in: Effects of Environment and Complex Load History on Fatigue Life, ASTM International100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, 1970: pp. 1 – 14. https://doi.org/10.1520/STP32032S. [8] M.D. Chapetti, Fatigue propagation threshold of short cracks under constant amplitude loading, Int J Fatigue 25 (2003) 1319 – 1326. https://doi.org/10.1016/S0142-1123(03)00065-3. [9] E. Brandl, F. Palm, V. Michailov, B. Viehweger, C. Leyens, Mechanical properties of additive manufactured titanium (Ti-6Al-4V) blocks deposited by a solid-state laser and wire, Mater Des 32 (2011) 4665 – 4675. https://doi.org/10.1016/j.matdes.2011.06.062. [10] B. Baufeld, E. Brandl, O. Van Der Biest, Wire based additive layer manufacturing: Comparison of microstructure and mechanical properties of Ti-6Al-4V components fabricated by laser-beam deposition and shaped metal deposition, J Mater Process Technol 211 (2011) 1146 – 1158. https://doi.org/10.1016/j.jmatprotec.2011.01.018. [11] S.H. Mok, G. Bi, J. Folkes, I. Pashby, J. Segal, Deposition of Ti-6Al-4V using a high power diode laser and wire, Part II: Investigation on the mechanical properties, Surf Coat Technol 202 (2008) 4613 – 4619. https://doi.org/10.1016/j.surfcoat.2008.03.028. [12] P. Åkerfeldt, M.L. Antti, R. Pederson, Influence of microstructure on mechanical properties of laser metal wire-deposited Ti-6Al-4V, Materials Science and Engineering: A 674 (2016) 428 – 437. https://doi.org/10.1016/j.msea.2016.07.038. [13] F. Klocke, K. Arntz, N. Klingbeil, M. Schulz, Wire-based laser metal deposition for additive manufacturing of TiAl6V4: basic investigations of microstructure and mechanical properties from build up parts, in: Laser 3D Manufacturing IV, SPIE, 2017: p. 100950U. https://doi.org/10.1117/12.2251336. [14] ASTM, E8-04: Standard Test Methods for Tension Testing of Metallic Materials, West Conshohocken, PA, 2004. [15] ASTM, E466-15: Standard Practice for Conducting Force Controlled Constant Amplitude Axial Fatigue Tests of Metallic Materials, ASTM International, West Conshohocken, PA, 2015. https://doi.org/10.1520/E0466-15. [16] W.J. Dixon, A.M. Mood, A Method for Obtaining and Analyzing Sensitivity Data, J Am Stat Assoc 43 (1948) 109 – 126. https://doi.org/10.1080/01621459.1948.10483254. [17] ASTM, E399-12: Standard Test Method for Linear-Elastic Plane-Strain Fracture Toughness KIc of Metallic Materials, ASTM International, West Conshohocken, PA, 2012. https://doi.org/10.1520/E0399-12E02. [18] ASTM, E647-15: Standard Test Method for Measurement of Fatigue Crack Growth Rates, ASTM International, West Conshohocken, PA, 2015. https://doi.org/10.1520/E0647-15. [19] F.. Liard, Helicopter fatigue design guide, North Atlantic Treaty Organization, Advisory Group for Aerospace Research and Development, 1983. [20] T.H. Becker, P. Kumar, U. Ramamurty, Fracture and fatigue in additively manufactured metals, Acta Mater 219 (2021). https://doi.org/10.1016/j.actamat.2021.117240. [21] M. Madarieta-Churruca, J.L. Arrizabalaga, I. Garmendia-Sáez-de-Heredia, C. Soriano, Comparative study of laser metal deposition (LMD) of coaxial wire and powder in the manufacture of Ti-6Al-4V structures, Dyna Ingeniería e Industria 95 (2020) 376 – 379. https://doi.org/10.6036/9378.

10