Effect of laser power on microstructure and mechanical properties of Nd: YAG laser welding of titanium tubes

Abstract

In this work, Nd: YAG laser beam welding was applied to join the grade 2 titanium tubes. Metallurgical characterization and mechanical tests were carried out to study the effect of laser power. The findings showed that when power increased, the bead geometry shape changed from wedge to parallel. The weld zone displayed a rough, uneven, and serrated coarse granular texture. The laser power had a significant impact on the misorientation angle patterns. High laser power revealed large pores. In the weld zone, dislocation pattern with high density and more sub grain boundaries were seen. The weld zone was strengthened during laser welding and less strengthening was observed at higher laser power in microhardness analysis. Higher tensile strength was achieved at lower laser power. The ductile failure was observed due to fine voids in the fracture surface analysis.

Keywords

laser beam welding / titanium tube joints / microstructure / hardness / tensile strength

References

[1] QuaziM M, IshakM, FazalM A, et al. . Current research and development status of dissimilar materials laser welding of titanium and its alloys [J]. Optics & Laser Technology, 2020, 126: 106090

[2] DewanganS, SinghalP. Study and comparison of microstructures in Ti-alloy before and after the heat treatment [J]. Materials Today: Proceedings, 2022, 621570-1574

[3] DewanganS, NagubandiT S, MishraV, et al. . Discussion and analysis of microstructural variation in welded joint of Ti-alloy after heat treatment [J]. AIP Conference Proceedings, 2021, 2341(1): 040027

[4] LeeY, CheonJ, MinB K, et al. . Optimization of gas shielding for the vacuum laser beam welding of Ti-6Al-4V titanium alloy [J]. The International Journal of Advanced Manufacturing Technology, 2022, 12331297-1305

[5] ZouP-y, ZhangH, LeiM, et al. . Formation mechanism of direct laser welding joint between CFRTP and Ti-6Al-4V [J]. Materials Letters, 2022, 325: 132707

[6] ZhangP-l, JiaZ-y, YanH, et al. . Effect of deposition rate on microstructure and mechanical properties of wire arc additive manufacturing of Ti-6Al-4V components [J]. Journal of Central South University, 2021, 28(4): 1100-1110

[7] DaiJ-j, ZhuJ-y, ChenC-z, et al. . High temperature oxidation behavior and research status of modifications on improving high temperature oxidation resistance of titanium alloys and titanium aluminides: A review [J]. Journal of Alloys and Compounds, 2016, 685784-798

[8] WangP, ChenF-h, EckertJ, et al. . Microstructural evolution and mechanical properties of selective laser melted Ti-6Al-4V induced by annealing treatment [J]. Journal of Central South University, 2021, 28(4): 1068-1077

[9] KumarU, AnsariK, KumarP, et al. . Transient thermal analysis of laser beam welding of titanium alloy sheet [J]. Materials Today: Proceedings, 2022, 63: 510-514

[10] KarpagarajA, SivaS N, SankaranarayanasamyK. Some studies on mechanical properties and microstructural characterization of automated TIG welding of thin commercially pure titanium sheets [J]. Materials Science and Engineering A, 2015, 640: 180-189

[11] SubramaniyanM K, VeemanD, NallathambhiS S, et al. . Gas tungsten arc welding of Ti-6Al-4V sheet for pressure vessels used in aerospace application: A detailed characterization of weldment [J]. International Journal of Pressure Vessels and Piping, 2022, 200: 104787

[12] DEWANGAN S. Effect of heat treatment into tensile strength, hardness and microstructural attributes of TIG welded Ti-6Al-4V titanium alloy [J]. Australian Journal of Mechanical Engineering, 2022. DOI: https://doi.org/10.1080/14484846.2022.2059906.

[13] WuM-y, XinR-l, WangY, et al. . Microstructure, texture and mechanical properties of commercial high-purity thick titanium plates jointed by electron beam welding [J]. Materials Science and Engineering A, 2016, 67750-57

[14] st WęglowskiM, BłachaS, PhillipsA. Electron beam welding—Techniques and trends—Review [J]. Vacuum, 2016, 130: 72-92

[15] FujiiH, SunY-f, KatoH, et al. . Investigation of welding parameter dependent microstructure and mechanical properties in friction stir welded pure Ti joints [J]. Materials Science and Engineering A, 2010, 527(15): 3386-3391

[16] EdwardsP D, RamuluM. Material flow during friction stir welding of Ti-6Al-4V [J]. Journal of Materials Processing Technology, 2015, 218: 107-115

[17] WangJ-y, SuJ-q, MishraR S, et al. . Tool wear mechanisms in friction stir welding of Ti-6Al-4V alloy [J]. Wear, 2014, 321: 25-32

[18] HattinghD G, vonW L G, BernardD, et al. . Semiautomatic friction stir welding of 38 mm OD 6082-T6 aluminium tubes [J]. Journal of Materials Processing Technology, 2016, 238: 255-266

[19] RominiyiA L, MashininiP M. Continuous wave laser welding of Ti6Al4V alloy joints: Microstructure and mechanical properties [J]. Materials Letters, 2023, 336: 133934

[20] ChenJ-c, ChenX-m, LiuX-j, et al. . Numerical investigation on keyhole collapsing and rebuilding behavior during pulsed laser beam welding of Ti6Al4V titanium alloy under various pulse frequencies [J]. Applied Physics A, 2022, 128(2): 140

[21] GaoX-l, ZhangL-j, LiuJ, et al. . A comparative study of pulsed Nd: YAG laser welding and TIG welding of thin Ti6Al4V titanium alloy plate [J]. Materials Science and Engineering A, 2013, 55914-21

[22] DuttaM J, MannaI. Laser material processing [J]. International Materials Reviews, 2011, 56(5–6): 341-388

[23] HongK M, ShinY C. Prospects of laser welding technology in the automotive industry: A review [J]. Journal of Materials Processing Technology, 2017, 24546-69

[24] PadmanabanG, BalasubramanianV. Optimization of laser beam welding process parameters to attain maximum tensile strength in AZ31B magnesium alloy [J]. Optics & Laser Technology, 2010, 42(8): 1253-1260

[25] LiuS, MiG-y, YanF, et al. . Correlation of high power laser welding parameters with real weld geometry and microstructure [J]. Optics & Laser Technology, 2017, 94: 59-67

[26] LiC, MuneharuaK, TakaoS, et al. . Fiber laser-GMA hybrid welding of commercially pure titanium [J]. Materials & Design, 2009, 30(1): 109-114

[27] LiuH, NakataK, YamamotoN, et al. . Mechanical properties and strengthening mechanisms in laser beam welds of pure titanium [J]. Science and Technology of Welding and Joining, 2011, 16(7): 581-585

[28] GaoX-l, ZhangL-j, LiuJ, et al. . Porosity and microstructure in pulsed Nd: YAG laser welded Ti6Al4V sheet [J]. Journal of Materials Processing Technology, 2014, 214(7): 1316-1325

[29] CarvalhoS M, BaptistaC A R P, LimaM S F. Fatigue in laser welded titanium tubes intended for use in aircraft pneumatic systems [J]. International Journal of Fatigue, 2016, 90: 47-56

[30] MaawadE, GanW-m, HofmannM, et al. . Influence of crystallographic texture on the microstructure, tensile properties and residual stress state of laser-welded titanium joints [J]. Materials & Design, 2016, 101: 137-145

[31] AhnJ, ChenL, DaviesC M, et al. . Parametric optimisation and microstructural analysis on high power Yb-fibre laser welding of Ti-6Al-4V [J]. Optics and Lasers in Engineering, 2016, 86: 156-171

[32] KashaevN, PugachevD, VentzkeV, et al. . Microstructure and mechanical performance of autogenously fibre laser beam welded Ti-6242 butt joints [J]. Materials Science and Engineering A, 2017, 694: 110-120

[33] ZhanX-h, PengQ-y, WeiY-h, et al. . Experimental and simulation study on the microstructure of TA15 titanium alloy laser beam welded joints [J]. Optics & Laser Technology, 2017, 94: 279-289

[34] ZhangK-z, NiL-c, LeiZ-l, et al. . In situ investigation of the tensile deformation of laser welded Ti₂AlNb joints [J]. Materials Characterization, 2017, 123: 51-57

[35] TsayL W, ShanY P, ChaoY H, et al. . The influence of porosity on the fatigue crack growth behavior of Ti-6Al-4V laser welds [J]. Journal of Materials Science, 2006, 41(22): 7498-7505

[36] ChattopadhyayA, MuvvalaG, SarkarS, et al. . Mitigation of cracks in laser welding of titanium and stainless steel by in-situ nickel interlayer deposition [J]. Journal of Materials Processing Technology, 2022, 300117403

[37] KangX-f, YanT-y, WangL-l, et al. . Study on the distribution, element characteristics, and formation mechanism of porosity during laser welding for Ti-6Al-4V bottom-locking joint [J]. The International Journal of Advanced Manufacturing Technology, 2022, 123(7): 2691-2701

[38] KimS K, ParkJ K. In-situ measurement of continuous cooling β → α transformation behavior of CP-Ti [J]. Metallurgical and Materials Transactions A, 2002, 33(4): 1051-1056

[39] OhM S, LeeJ Y, ParkJ K. Continuous cooling β-to-α transformation behaviors of extra-pure and commercially pure Ti [J]. Metallurgical and Materials Transactions A, 2004, 35(10): 3071-3077

[40] GuptaA, KhatirkarR, SinghJ. A review of microstructure and texture evolution during plastic deformation and heat treatment of β-Ti alloys [J]. Journal of Alloys and Compounds, 2022, 899163242

[41] GeyN, HumbertM. Characterization of the variant selection occurring during the α → β → α phase transformations of a cold rolled titanium sheet [J]. Acta Materialia, 2002, 50(2): 277-287

[42] ZhangT-l, LiuC T. Design of titanium alloys by additive manufacturing: A critical review [J]. Advanced Powder Materials, 2022, 1(1): 100014

[43] GermainL, GeyN, HumbertM. Reliability of reconstructed β-orientation maps in titanium alloys [J]. Ultramicroscopy, 2007, 107121129-1135

[44] ThompsonA W. Substructure strengthening mechanisms [J]. Metallurgical Transactions A, 1977, 8(6): 833-842

[45] BolzoniL, RaynovaS, YangF. Strengthening mechanisms of Ti via Al addition [J]. Journal of Alloys and Compounds, 2020, 820153447