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Role of plasma gas flow rate on the microstructural and mechanical aspects of plasma arc welded titanium alloy joints


Affiliations
1 Centre for Materials Joining & Research (CEMAJOR), Annamalai University, Annamalai Nagar, Tamil Nadu, India, India
2 Centre for Materials Joining & Research (CEMAJOR), Annamalai University, Annamalai Nagar, Tamil Nadu, India., India
     

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In the present investigation, the effect and role of plasma gas flow rate on the formation of microstructure during plasma arc welding of Ti6Al4V titanium alloy were studied using microscopic observation, energy dispersive spectroscopic analysis, tensile tests and microhardness measurements. Plasma gas flow rate influences the arc pressure, arc constriction, and stability. The transformation of plasma arc from conduction mode to keyhole mode causes severe changes to the microstructural characteristics of the titanium welds. This transformation takes place with slight variations of PGFR. Weld geometries increase with an increase in the PGFR. The microstructural examination shows that there are various phases formed during the variation in PGFR. Fusion zone had acicular α and widmanstätten α. Mechanical properties (i.e) strength and hardness of the joints increase with an increase in plasma gas flow rate. In the joint welded with 1 L/min, there is the formation of α-case which is an oxygen rich brittle subsurface structure and found detrimental to the ductility of the joints.

Keywords

Plasma Arc Welding, Titanium Alloy, Microstructure, Defects, Tensile, Hardness.
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  • Balasubramanian, T. S., Balakrishnan, M., Balasubramanian, V., & Muthu Manickam, M. A. (2011). Effect of welding processes on joint characteristics of Ti-6Al-4v alloy. Science and Technology of Welding and Joining, 16(8), 702-708. https://doi.org/10.1179/1362171811 Y.0000000062

  • Balasundar, I., Raghu, T., & Kashyap, B. P. (2019). Correlation between microstructural features and tensile properties in near-α titanium alloy IMI 834 processed in the α + β regime. Materials Performance and Characterization, 8(5), 932-945. https://doi.org/10.1520/MPC 20180162

  • Baruah, M., & Bag, S. (2016). Microstructural Influence on Mechanical Properties in Plasma Microwelding of Ti6Al4V Alloy. Journal of Materials Engineering and Performance, 25(11), 4718-4728. https://doi.org/10.1007/ s11665-016-2333-8

  • Brewer, W. D., Bird, R. K., & Wallace, T. A. (1998). Titanium alloys and processing for high speed aircraft. Materials Science and Engineering A, 243(1-2), 299-304. https://doi.org/10.1016/ s0921-5093(97)00818-6

  • Chen, J. C., & Pan, C. X. (2011). Welding of Ti-6Al-4V alloy using dynamically controlled plasma arc welding process. Transactions of Nonferrous Metals Society of China (English Edition), 21(7), 1506–1512. https://doi.org/10.1016/S1003-63 26(11)60888-1

  • Deshpande, A. A., Short, A. B., Sun, W., McCartney, D. G., Xu, L., & Hyde, T. H. (2012). Finite elementbased analysis of experimentally identified parametric envelopes for stable keyhole plasma arc welding of a titanium alloy. Journal of Strain Analysis for Engineering Design, 47(5), 266–275. https://doi.org/10.1177/0309 324712445417

  • Kumar, P., & Sinha, A. N. (2019). Effect of heat input in pulsed Nd: YAG laser welding of titanium alloy (Ti6Al4V) on microstructure and mechanical properties. Welding in the World, 63(3), 673-689. https://doi.org/10.1007/s401 94-018-00694-w

  • Leonov, V. P., Mikhailov, V. I., Sakharov, I. Y., & Kuznetsov, S. V. (2016). Welding of high-strength titanium alloys of large thicknesses for use in marine environments. Inorganic Materials: Applied Research, 7(6), 877-883. https://doi. org/10.1134/S2075113316060083

  • Leyens, C. (2005). Oxidation and Protection of Titanium Alloys and Titanium Aluminides. Titanium and Titanium Alloys, 187-230. https:// doi.org/10.1002/3527602119.ch6

  • Lukoyanov, A. V. (2014). Formation of pores in the weld metal in automatic argon-shielded arc welding of titanium alloys. Welding International, 28(4), 301-303. https://doi.org/1 0.1080/09507116.2013.796682

  • Murav’ev, V. I., Krupskii, R. F., Fizulakov, R. A., & Demyshev, P. G. (2008). Effect of the quality of filler wire on the formation of pores in welding of titanium alloys. Welding International, 22(12), 853-858.

  • Muth, T. R., Yamamoto, Y., Frederick, D. A., Contescu, C. I., Chen, W., Lim, Y. C., Peter, W. H., & Feng, Z. (2013). Causal factors of weld porosity in gas tungsten arc welding of powder-metallurgyproduced titanium alloys. JOM, 65(5), 643–651. https://doi.org/10.1007/s11837-013-0592-5

  • Pantelis, D. I., Kazasidis, M., & Karakizis, P. N. (2017). Titanium Alloys Thin Sheet Welding with the Use of Concentrated Solar Energy. Journal of Materials Engineering and Performance, 26(12), 5760–5768. https://doi.org/10.1007/ s11665-017-3049-0

  • Peters, M., Hemptenmacher, J., Kumpfert, J., & Leyens, C. (2005). Structure and Properties of Titanium and Titanium Alloys. In Titanium and Titanium Alloys, 1-36.

  • Peters, M., Kumpfert, J., Ward, C. H., & Leyens, C. (2003). Titanium alloys for aerospace applications. Advanced Engineering Materials, 5(6), 419–427. https://doi.org/10.1002/adem. 200310095 Short, A. B. (2009). Gas tungsten arc welding of α + β titanium alloys: A review. Materials Science and Technology, 25(3), 309-324. https://doi. org/10.1179/174328408X389463

  • Sibum, H. (2003). Titanium and titanium alloys - From raw material to semi-finished products. Advanced Engineering Materials, 5(6). https:// doi.org/10.1002/adem.200310092

  • Sun, W., Mohammed, M. B., Xu, L., Hyde, T. H., McCartney, D. G., & Leen, S. B. (2014). Process modelling and optimization of keyhole plasma arc welding of thin Ti-6Al-4V. Journal of Strain Analysis for Engineering Design, 49(6), 410-420. https://doi.org/10.1177/0309324714524947

  • Sundaresan, S., & Janaki Ram, G. D. (1999). Use of magnetic arc oscillation for grain refinement of gas tungsten arc welds in α-β titanium alloys. Science and Technology of Welding and Joining, 4(3), 151–160. https://doi. org/10.1179/136217199101537699

  • Vasechkin, M. A., Davydov, O. Y., Kolomenskii, A. B., & Egorov, S. V. (2018). Effect of Welding and Heat Treatment Regimes on the Mechanical Properties of Various Titanium Alloy Welded Joints. Chemical and Petroleum Engineering, 54(7-8), 525–530. https://doi.org/10.1007/ s10556-018-0512-1

  • Vyskoč, M., Sahul, M., & Sahul, M. (2018). Effect of Shielding Gas on the Properties of AW 5083 Aluminum Alloy Laser Weld Joints. Journal of Materials Engineering and Performance, 27(6), 2993–3006. https://doi.org/10.1007/s11665- 018-3383-x


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  • Role of plasma gas flow rate on the microstructural and mechanical aspects of plasma arc welded titanium alloy joints

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Authors

T. Pragatheswaran
Centre for Materials Joining & Research (CEMAJOR), Annamalai University, Annamalai Nagar, Tamil Nadu, India, India
S. Rajakumar
Centre for Materials Joining & Research (CEMAJOR), Annamalai University, Annamalai Nagar, Tamil Nadu, India., India
V. Balasubramanian
Centre for Materials Joining & Research (CEMAJOR), Annamalai University, Annamalai Nagar, Tamil Nadu, India, India

Abstract


In the present investigation, the effect and role of plasma gas flow rate on the formation of microstructure during plasma arc welding of Ti6Al4V titanium alloy were studied using microscopic observation, energy dispersive spectroscopic analysis, tensile tests and microhardness measurements. Plasma gas flow rate influences the arc pressure, arc constriction, and stability. The transformation of plasma arc from conduction mode to keyhole mode causes severe changes to the microstructural characteristics of the titanium welds. This transformation takes place with slight variations of PGFR. Weld geometries increase with an increase in the PGFR. The microstructural examination shows that there are various phases formed during the variation in PGFR. Fusion zone had acicular α and widmanstätten α. Mechanical properties (i.e) strength and hardness of the joints increase with an increase in plasma gas flow rate. In the joint welded with 1 L/min, there is the formation of α-case which is an oxygen rich brittle subsurface structure and found detrimental to the ductility of the joints.

Keywords


Plasma Arc Welding, Titanium Alloy, Microstructure, Defects, Tensile, Hardness.

References