Plasma transfer arc additive manufacturing of 17-4 PH: assessment of defects


Plasma transferred arc additive manufacturing is a growing technology in the additive manufacturing world. The plasma transferred arc additive manufacturing system’s ability to produce large samples, compared with other common additive manufacturing techniques, makes it highly desirable in many industrial applications. The selected material in this additive process is 17-4 precipitation hardened stainless steel, which is widely used in numerous fields, such as the aerospace, chemical, and mining industries. However, two types of voids were found in the deposits and these voids are detrimental to the mechanical properties. The identified voids were oxide layers and porosity. The presence of oxide layers was correlated to the interaction of atmospheric oxygen with the chromium present in the stainless steel. A shielding hood was designed to provide continuous shielding with inert gas to prevent oxide layer formation. The other source of voids was attributed to the porosity in the initial powders and to the choice of welding process parameters. Changing the powder supplier and optimizing the process parameters, mainly by increasing the heat input to ensure complete melting of the powders, greatly reduced the amount of porosity in the finished part. Hardness measurements were obtained from multiple samples. Hardness was only affected by the aging process, during which copper precipitates formed within the 17-4 precipitation hardened stainless steel matrix. X-ray diffraction and transmission electron microscopy analyses were conducted to characterize the martensitic matrix before and after the heat treatment and to view copper precipitation after the heat treatment. It is demonstrated that an operating solution to avoid oxide formation is the use of 5% hydrogen in the shield, center, and powder gas feeds.

This is a preview of subscription content, log in to check access.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11
Fig. 12
Fig. 13
Fig. 14
Fig. 15
Fig. 16
Fig. 17
Fig. 18
Fig. 19
Fig. 20


  1. 1.

    Zadi-Maad A, Rohib R, Irawan A (2018) Additive manufacturing for steels: a review. IOP Conf Ser Mater Sci Eng 012–028.

  2. 2.

    Mercado Rojas JG, Wolfe T, Fleck BA, Qureshi AJ (2018) Plasma transferred arc additive manufacturing of nickel metal matrix composites. Manuf Lett 18:31–34.

    Article  Google Scholar 

  3. 3.

    Nowacki J (2004) Weldability of 17-4 PH stainless steel in centrifugal compressor impeller applications. J Mater Process Technol 578–583.

  4. 4.

    Murayama M, Katayama Y, Hono K (1999) Microstructural evolution in a 17-4 PH stainless steel after aging at 400 °C. Metall Mater Trans A Phys Metall Mater Sci 30:345–353.

    Article  Google Scholar 

  5. 5.

    Tavakoli Shoushtari MR, Moayed MH, Davoodi A (2010) Post-weld heat treatment influence on galvanic corrosion of GTAW of 17-4PH stainless steel in 3·5%NaCl. Corros Eng Sci Technol 46:415–424.

    Article  Google Scholar 

  6. 6.

    Hsiao CN, Chiou CS, Yang JR (2002) Aging reactions in a 17-4 PH stainless steel. Mater Chem Phys 74:134–142.

    Article  Google Scholar 

  7. 7.

    Hu Z, Zhu H, Zhang H, Zeng X (2017) Experimental investigation on selective laser melting of 17-4PH stainless steel. Opt Laser Technol 87:17–25.

    Article  Google Scholar 

  8. 8.

    Yeli G, Auger MA, Wilford K, Smith GDW, Bagot PAJ, Moody MP (2017) Sequential nucleation of phases in a 17-4PH steel: microstructural characterisation and mechanical properties. Acta Mater 125:38–49.

    Article  Google Scholar 

  9. 9.

    Isogawa S, Yoshida H, Hosoi Y, Tozawa Y (1998) Improvement of the forgability of 17-4 precipitation hardening stainless steel by ausforming. J Mater Process Technol 74:298–306.

    Article  Google Scholar 

  10. 10.

    Viswanathan UK, Banerjee S, Krishnan R (1988) Effects of aging on the microstructure of 17-4 PH stainless steel. Mater Sci Eng 104:181–189.

    Article  Google Scholar 

  11. 11.

    Wu MW, Huang ZK, Tseng CF, Hwang KS (2015) Microstructures, mechanical properties, and fracture behaviors of metal-injection molded 17-4PH stainless steel. Met Mater Int 21:531–537.

    Article  Google Scholar 

  12. 12.

    Song B, Zhao X, Li S, Han C, Wei Q, Wen S, Liu J, Shi Y (2015) Differences in microstructure and properties between selective laser melting and traditional manufacturing for fabrication of metal parts: a review. Front Mech Eng 10:111–125.

    Article  Google Scholar 

  13. 13.

    Alberti EA, Bueno BMP, D’Oliveira ASCM (2016) Additive manufacturing using plasma transferred arc. Int J Adv Manuf Technol 83:1861–1871.

    Article  Google Scholar 

  14. 14.

    Liyanage T, Fisher G, Gerlich AP (2012) Microstructures and abrasive wear performance of PTAW deposited Ni-WC overlays using different Ni-alloy chemistries. Wear. 274–275:345–354.

    Article  Google Scholar 

  15. 15.

    Liyanage T, Fisher G, Gerlich AP (2010) Influence of alloy chemistry on microstructure and properties in NiCrBSi overlay coatings deposited by plasma transferred arc welding (PTAW). Surf Coat Technol 205:759–765.

    Article  Google Scholar 

  16. 16.

    Ngo TD, Kashani A, Imbalzano G, Nguyen KTQ, Hui D (2018) Additive manufacturing (3D printing): a review of materials, methods, applications and challenges. Compos Part B Eng 143:172–196.

    Article  Google Scholar 

  17. 17.

    Nezhadfar PD, Masoomi M, Thompson SM, Phan N, Shamsaei N (2017) Mechanical properties of 17-4 PH stainless steel additively manufactured under Ar and N2 shielding gas. Solid Free Fabr Symp 2430–2446

  18. 18.

    Huang PH, Guo MJ (2015) A study on the investment casting of 17-4PH stainless steel helical impeller of centrifugal pump. Mater Res Innov 19:S977–S981.

    Article  Google Scholar 

  19. 19.

    Toyserkani E, Khajepour A, Corbin SF, Khajepour A, Corbin SF (2004) Laser cladding. CRC Press.

  20. 20.

    Yen SK (2006) Determination of the critical temperature for forming a chromium-rich oxide on AISI 430 stainless steel and its corrosion resistance. J Electrochem Soc 143:2493.

    Article  Google Scholar 

  21. 21.

    Peter R, Saric I, Piltaver IK, Badovinac IJ, Petravic M (2017) Oxide formation on chromium metal surfaces by low-energy oxygen implantation at room temperature. Thin Solid Films 636:225–231.

    Article  Google Scholar 

  22. 22.

    Slotwinski JA, Garboczi EJ (2014) Porosity of additive manufacturing parts for process monitoring. AIP Conf Proc 1197–1204.

  23. 23.

    Fayazfar H, Salarian M, Rogalsky A, Sarker D, Russo P, Paserin V, Toyserkani E (2018) A critical review of powder-based additive manufacturing of ferrous alloys: process parameters, microstructure and mechanical properties. Mater Des 144:98–128.

    Article  Google Scholar 

  24. 24.

    Frazier WE (2014) Metal additive manufacturing: a review. J Mater Eng Perform 23:1917–1928.

    Article  Google Scholar 

  25. 25.

    Paul R, Anand S, Gerner F (2014) Effect of thermal deformation on part errors in metal powder based additive manufacturing processes. J Manuf Sci Eng 136:031009.

    Article  Google Scholar 

  26. 26.

    Susan DF, Crenshaw TB, Gearhart JS (2015) The effects of casting porosity on the tensile behavior of investment cast 17-4PH stainless steel. J Mater Eng Perform 24:2917–2924.

    Article  Google Scholar 

  27. 27.

    Ferguson JB, Schultz BF, Moghadam AD, Rohatgi PK (2015) Semi-empirical model of deposit size and porosity in 420 stainless steel and 4140 steel using laser engineered net shaping. J Manuf Process 19:163–170.

    Article  Google Scholar 

  28. 28.

    Tillmann W, Schaak C, Nellesen J, Schaper M, Aydinöz ME, Hoyer KP (2017) Hot isostatic pressing of IN718 components manufactured by selective laser melting. Addit Manuf 13:93–102.

    Article  Google Scholar 

  29. 29.

    Alsalla HH, Smith C, Hao L (2018) Effect of build orientation on the surface quality, microstructure and mechanical properties of selective laser melting 316L stainless steel. Rapid Prototyp J 24:9–17.

    Article  Google Scholar 

  30. 30.

    Davies RG (1978) Influence of martensite composition and content on the properties of dual phase steels. Metall Trans A 9:671–679.

    Article  Google Scholar 

  31. 31.

    Xiao L, Fan Z, Jinxiu Z, Mingxing Z, Mokuang K, Zhenqi G (1995) Lattice-parameter variation with carbon content of martensite. I. X-ray-diffraction experimental study. Phys Rev B 52:9970–9978.

    Article  Google Scholar 

  32. 32.

    Luo Q (2016) A new XRD method to quantify plate and lath martensites of hardened medium-carbon steel. J Mater Eng Perform 25:2170–2179.

    Article  Google Scholar 

  33. 33.

    Schroeder R, Hammes G, Binder C, Klein AN (2011) Plasma debinding and sintering of metal injection moulded 17-4PH stainless steel. Mater Res 14:564–568.

    Article  Google Scholar 

  34. 34.

    Lu Y, Yu H, Sisson RD (2017) The effect of carbon content on the c/a ratio of as-quenched martensite in Fe-C alloys. Mater Sci Eng A 700:592–597.

    Article  Google Scholar 

  35. 35.

    Onsoien M, Peters R, Olson DL, Liu S (1995) Effect of hydrogen in an argon GTAW shielding gas: arc characteristics and bead morphology. Weld J (Miami, Fla) 74:10-s

    Google Scholar 

  36. 36.

    Durgutlu A (2004) Experimental investigation of the effect of hydrogen in argon as a shielding gas on TIG welding of austenitic stainless steel. Mater Des 25:19–23.

    Article  Google Scholar 

  37. 37.

    Tusek J, Suban M (2000) Experimental research of the effect of hydrogen in argon as a shielding gas in arc welding of high-alloy stainless steel. Int J Hydrog Energy 25:369–376.

    Article  Google Scholar 

  38. 38.

    Wang L, Pratt P, Felicelli S, Kadiri H, Wang P (2009) Experimental analysis of porosity formation in laser-assisted powder deposition process. TMS (The Miner Met Mater Soc) 1:389–396 Accessed 22 May 2019

    Google Scholar 

Download references


The authors would like to acknowledge the help and support received from Dr. J. Barry Wiskel, Dr. Ahmed Qureshi, and Professor Leijun Li from the University of Alberta. Dylan Rose and Jose Mercado Rojas, Dr. Jonas Valloton, and Dr. Abdoul-Aziz Bogno, also from the University of Alberta, are also acknowledged for their help with data analysis, as is Mr. Mike Danysh, at InnoTech Alberta, for assistance with the PTA-AM system.


This project received funding from the Natural Sciences and Engineering Research Council (NSERC) of Canada and Syncrude.

Author information



Corresponding author

Correspondence to Sandy N. El Moghazi.

Additional information

Publisher’s note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

El Moghazi, S.N., Wolfe, T., Ivey, D.G. et al. Plasma transfer arc additive manufacturing of 17-4 PH: assessment of defects. Int J Adv Manuf Technol 108, 2301–2313 (2020).

Download citation


  • Plasma transferred arc
  • Additive manufacturing
  • 17-4PH stainless steel
  • Voids
  • Oxide layer
  • Porosity
  • Hardness