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Metallurgical and Materials Transactions A
Erschienen in: Metallurgical and Materials Transactions A 9/2018

01.06.2018 | Topical Collection: Superalloys and Their Applications

Additive Manufacturing of Nickel Superalloys: Opportunities for Innovation and Challenges Related to Qualification

verfasst von: S. S. Babu, N. Raghavan, J. Raplee, S. J. Foster, C. Frederick, M. Haines, R. Dinwiddie, M. K. Kirka, A. Plotkowski, Y. Lee, R. R. Dehoff

Erschienen in: Metallurgical and Materials Transactions A | Ausgabe 9/2018

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Abstract

Innovative designs for turbines can be achieved by advances in nickel-based superalloys and manufacturing methods, including the adoption of additive manufacturing. In this regard, selective electron beam melting (SEBM) and selective laser melting (SLM) of nickel-based superalloys do provide distinct advantages. Furthermore, the direct energy deposition (DED) processes can be used for repair and reclamation of nickel alloy components. The current paper explores opportunities for innovation and qualification challenges with respect to deployment of AM as a disruptive manufacturing technology. In the first part of the paper, fundamental correlations of processing parameters to defect tendency and microstructure evolution will be explored using DED process. In the second part of the paper, opportunities for innovation in terms of site-specific control of microstructure during processing will be discussed. In the third part of the paper, challenges in qualification of AM parts for service will be discussed and potential methods to alleviate these issues through in situ process monitoring, and big data analytics are proposed.
Vorheriger Artikel Foreword
Nächster Artikel Microstructure and Mechanical Properties of CMSX-4 Single Crystals Prepared by Additive Manufacturing

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Literatur
1.
2.
3.
4.
D. D. Gu, W. Meiners, K. Wissenbach, and R. Poprawe, Int. Mater. Rev., 2012, vol. 57, pp. 133-164CrossRef
5.
B. Ealy, L. Calderon, W. Wang, R. Valentin, I. Mingareev, M. Richardson, J. Kapat, J. Eng. Gas Turbines Power, 2017, Vol. 139, p. 102102CrossRef
6.
C. K. Stimpson, J. C. Snyder, K. A. Thole, D. Mongillo, J. Turbomach., 2017, Vol. 139, p. 021003CrossRef
7.
K. L. Kirsch and K. A. Thole, Int. J. Heat Mass Transf., 2017, Vol. 108, pp. 2502-2513CrossRef
8.
9.
L. E. Murr, E. Martinez, X. M. Pan, S. M. Gaytan, J. A. Castro, C. A. Terrazas, F. Medina, R. B. Wicker and D. H. Abbott, Acta Mater, 2013, Vol. 61, pp. 4289-4296CrossRef
10.
H. Helmer, A. Bauereiβ, R. F. Singer, and C. Körner, Mater. Sci. Eng. A, 2016, Vol. 668, pp. 180-187CrossRef
11.
M. Rambsperger, R. F. Singer, and C. Korner, Metall. Mater. Trans. A, 2016, Vol. 47A, pp. 1469-1480CrossRef
12.
N. J. Harrison, I. Todd, and K. Mumtaz, Acta Mater., 2015, Vol. 94, pp. 59-68CrossRef
13.
A. Basak, R. Acharya, and S. Das, Metall. Mater. Trans. A, 2016, Vol. 47A, pp. 3845-3859CrossRef
14.
S. Das, D. L. Bourell and S. S. Babu, MRS Bull., 2016, Vol. 14, pp. 729-741CrossRef
15.
S. S. Babu, L. Love, R. Dehoff, W. Peter, T. Watkins and S. Pannala, MRS Bull., 2015, Vol. 40, pp. 1154-1161CrossRef
16.
Y. Tian, D. McAllister, H. Colijn, M. Mills, D. F. Farson, M. C. Nordin, and S. S. Babu, Metall. Mater. Trans.A, 2014, Vol. 45, pp. 4470-4483CrossRef
17.
T. Debroy, H. L. Wei, J. S. Zuback, T. Mukerjee, J. W. Elmer, J. O. Milewski, A. M. Beese, A. Wislon-heid, A. De and W. Zhang, Prog. Mater. Sci., 2018, Vol. 92, pp. 112-224CrossRef
18.
W. Sames, F. A. List, S. Pannala, R. R. Dehoff and S. S. Babu, Int. Mater. Rev., 2016, Vol. 61, pp. 315-360CrossRef
19.
S. J. Foster, S. S. Babu and A. Chaudhary, Unpublished Research, University of Tennessee, Knoxville, 2018
20.
R. C. Reed and H. K. D. H. Bhadeshia, Acta Metall. Mater., 1994, Vol. 42, pp. 3663-3678CrossRef
21.
S. S. Babu, R. A. Martukanitz, K. D. Parks, and S. A. David., Metall. Mater. Trans.A, 2002, vol. 33A, pp. 1189-1200CrossRef
22.
23.
A. C. Hall and C. V. Robino, Sci. Technol. Weld. Join., 2004, Vol. 9, pp. 103-108CrossRef
24.
J. C. Villafuerte, H. W. Kerr, and S. A. David., Mater. Sci. Eng. A, 1995, Vol. 194, pp.187-191CrossRef
25.
J. H. Martin, D. D. Yahata, J. M. Hundley, J. A. Meyer, T. A. Schaedler and T. M. Pollock, Nature, 2017, Vol. 549, pp. 365-369CrossRef
26.
O. M. Barabash, S. S. Babu, J. M. Vitek, S. A. David, J.-W. Park, J. A. Horton, G. E. Ice, and R. I. Barabash, J. Appl. Phys., 2004, vol. 96, pp. 3673-3679CrossRef
27.
Y. M. Wang, T. Voslin, J. T. Mckeown, J. Ye, N. P Calta, Z. Li, Z. Zeng, Y. Zhang, W. Chen, T. T. Roehling, R. T. Ott, M. K. Santala, P. J. Depond, M. J. Matthews, A. V. Hamza and T. Zhu, Nat. Mater., 2018, Vol. 17, pp. 63-70CrossRef
28.
D. Qiao, W. Zhang, T.-Y. Pan, P. Crooker, S. David and Z. Feng, Sci. Technol. Weld. Join., 2013, Vol. 18, pp. 624-630CrossRef
29.
L. Kolbus, A. Payzant, P. Cornwell, T. Watkins, S. S. Babu, R. Dehoff, and C. Duty, Metall. Mater. Trans. A, 2015, Vol. 46, Issue 3, pp. 1419-1432CrossRef
30.
D. Dye, O. Hunziker, R. C. Reed, Acta Mater., 2001, Vol. 49, pp. 683-697CrossRef
31.
I. Yadroitsev, A. Gusarov, I. Yadroitsava, I. Smurov, J. Mater. Process. Technol., 2010, Vol. 210, pp. 1624-1631CrossRef
32.
O. Grong, Metallurgical Modelling of Welding Materials Modeling Series, London, The Institute of Materials, 1994
33.
S.S. Babu, in Proceedings of 10th International Conference on Trends in Welding Research and 9th International Welding Symposium of Japan Welding Society (9WS), AWS, 2017
34.
A. Plotkowski, M. M. Kirka, and S. S. Babu, Addit. Manuf., 2017, Vol. 18, pp. 256-268CrossRef
35.
M. St. Weglowski, S. Blacha and A. Philips, Vacuum, 2016, Vol. 130, pp. 72-92CrossRef
36.
M. Gaumann, C. Bezencon, P. Canalis, and W. Kurz, Acta Mater., 2001, Vol. 49, pp. 1051-1062CrossRef
37.
Y. Fujita, K. Saida and K. Nishimoto, Mater. Sci. Forum, 2008, Vol. 580-582, pp. 67-70CrossRef
38.
J.-W. Park, J. M. Vitek, S. S. Babu, and S. A. David., Sci. Technol. Weld. Join., 2004, vol. 9, 472-482CrossRef
39.
M.L. Griffith, D.M. Keicher, C.L. Atwood, J.A. Romero, J.E. Smugeresky, L.D. Harwell, and D.L. Greene, 7th Solid Freeform Fabrication (SFF) Proceedings, 1996, pp. 125–31
40.
D. D. Gu, W. Meiners, K. Wissenbacj, R. Poprawe, Int. Mater. Rev., 2012, Vol. 57 pp. 136-164CrossRef
41.
42.
S.S. Babu, in Proceedings of the International conference on Solid-Solid Phase Transformations in Inorganic Materials 2015, Jun 28 to July 3, 2015, M. Millitzer, G. Botton, L.-Q. Chen, J. How, C. Sinclair, and H. Zurob, TMS, pp. 1019-26
43.
R. R. Dehoff, W. J. Sames, M. K. Kirka, H. Bilheux, A. S. Tremsin and S. S. Babu, Mater. Sci. Technol., 2015, Vol. 31, pp. 931-938CrossRef
44.
45.
Dantzig, J. and Rappaz, M., Solidification, 2nd ed, EPFL Press, Lausanne, 2017
46.
S. S. Babu, J. W. Elmer, S. A. David, and J. M. Vitek, Acta Mater., 2002, Vol. 50, pp. 4763-4781CrossRef
47.
48.
49.
N. Raghavan, A. Plotkowski, R. R. Dehoff, J. A. Turner, M. K. Kirka, and S. S. Babu, Acta Mater., 2017, Vol. 140, pp. 375-387CrossRef
50.
N. Raghavan, S. S. Babu. R. R. Dehoff, S. Pannala, S. Simunovic, M. K. Kirka, J. Turner and N. Carlson, Acta Mater., 2016, Vol. 112, pp. 303-314CrossRef
51.
M. Haines, C. Frederick, A. Plotkowski, and S.S. Babu, Unpublished research, UTK, 2018
52.
Y.S. Lee, M.M. Kirka, N. Raghavan, and, R.R. Dehoff, in Proceedings of Solid Freeform Fabrication 2017, pp. 1006-17
53.
54.
X. He, P. W. Fuerschbach, and T. DebRoy, J. Phys. D Appl. Phys., 2003, Vol. 12, pp. 1388-1398CrossRef
55.
J. Raplee, A. Plotkowski, M. Kirka, R. Dinwiddie, A. Okello, R. R. Dehoff and S. S. Babu, Sci. Rep. 2017, Vol. 7, 43554CrossRef
56.
S. S. Babu, M. K. Miller, J. M. Vitek, and S. A. David., Acta Mater., 2001, Vol. 49, pp. 4149-4160CrossRef
57.
Y.S. Lee, M.M. Kirka, S. Kim, N. Sridharan, A. Okello, R.R. Dehoff, and S.S. Babu: submitted to Metall. Mater. Trans. A, 2018
58.
Z. Feng, S. A. David, T. Zacharia and C. L. Tsai, Sci. Technol. Weld. Join., 1997, Vol. 2, pp. 11-19CrossRef
59.
Y. Yang, S.S. Babu, S. Vaze, J. Kikel and D. Dewees: Proceedings of Trends in Welding Research, ASM International, Pine Mountain, 2008.
60.
X. Wang, G. Han, C. Cui, S. Guan, T. Jin, X. Sun and Z. Hu, Metall. Mater. Trans. A, 2016, Vol. 47A, pp. 5994-6003CrossRef
61.
P. Fernandez-Zelaia, B. S. Adair, V. M. Barker and S. D. Antolovich, Metall. Mater. Trans. A, 2015, Vol. 46A, pp. 5596-5609CrossRef
62.
S. D. Antolovich and R. W. Armstrong, Prog. Mater. Sci., 2014, Vol. 59, pp. 1-160CrossRef
63.
W. Dieter and G. Mook, NDI for manufacturing Anomalies in Aero-Engine Rotor Disks, in Proceedings of ECNDT, 2006, Berlin
64.
E. Todorov, R. Spencer, S. Gleeson, M. Jamshidinia, and S.M. Kelly, America Makes: National Additive Manufacturing Innovation Institute: Project 1: Nondestructive Evaluation (NDE) of Complex Metallic Additive Manufactured (AM) structures, AFRL-RX-WP-TR-2014-0162, Interim Report, June 2014
65.
T. Watkins, H. Bilheux, K. An, A. Payzant, R. Dehoff, C. Duty, W. Peter, C. Blue and C. Brice, Adv. Mater. Process., 2013, Vol. 171, pp. 23-27
66.
S. Yoder, S. Morgan, E. Barnes, C. Kinzy, P. Nandwana, M. Kirka, S. S. Babu, V. Paquit, R. R. Dehoff, Addit. Manuf., 2018, Vol. 19, pp. 184-196CrossRef
67.
Y. Lee, M.M. Kirka, R.R. Dehoff, and S.S. Babu: Unpublished Research, UTK, 2018
68.
P. Prabhakar, W. J. Sames, R Smith, R. Dehoff, and S. S. Babu, Addit. Manuf., 2015, Vol. 7, pp. 83-91CrossRef
69.
C. A. Steed, W. Hasley, R. Dehoff, S. L. Yoder, V. Paquit, and S. Powers., Comput. Gr., 2017, Vol. 63, pp. 50-64CrossRef
70.
C. J. Smith, S. Tamma-Williams, E. Hernandez-Nava and I. Todd, Sci. Rep., 2017, Vol. 7, p. 10514CrossRef
71.
P. Nandwana, A. M. Elliott, D. Siddel, A. Merriman, W. H. Peter, and S. S. Babu, Curr. Opin. Mater. Sci., 2017, Vol. 21, pp. 207-218CrossRef
72.
R. Engeli, T. Etter, S. Hoverl, K. Wegener, J. Mater. Process. Technol., 2016, Vol. 229, pp. 484-491CrossRef
73.
U. Ackelid, Powder pre-processing for additive manufacturing, US Patent # 9,661,542B2, February 2017.
74.
L. N. Carter, X. Wang, N. Read, R. Khan, M. Aristizabal, K. Essa and M. M. Attallah, Mater. Sci. Technol., 2016, Vol. 32, pp. 657-661
75.
L. N. Carter, K. Essa, M. M. Attallah, Rapid Prototyp. J., 2015, Vol. 21, pp. 423-432CrossRef
76.
L.N. Carter, M.M. Attallah, and R.C. Reed, in Superalloys 2012, Proceedings edited by E.S. Huron, R.C. Reed, M.C. Hardy, M.J. Mills, R.E. Montero, P.D. Portella and J. Telesman, pp. 577-86
77.
S. Catchpole-Smith, N. Aboulkhair, L. Parry, C. Tuck, I. A. Ashcroft, A. Clare, Addit. Manuf., 2017, Vol. 15, pp. 113-122CrossRef
78.
79.
P. C. Collins, D. A. Brice, P. Samimi, I. Ghamarian and H. L. Fraser, Ann. Rev. Mater. Res., 2016, Vol. 46, pp. 63-91CrossRef
80.
R. Acharya, R. Bansal, J. J. Gambone and S. Das, Metall. Mater. Trans. B, 2014, Vol. 45B, pp. 2247-2261CrossRef
81.
N. J. Harrison, I. Todd, and K. Mumtaz, Acta Mater., 2015, Vol. 94, pp. 59-68CrossRef
82.
T. Mukherjee, J. S. Zuback, A. De and T. DebRoy, Sci. Rep., 2016, Vol. 6, p. 19717CrossRef
83.
X. Wang, L. N. Carter, B. Pang, M. M. Attallah and M. H. Loretto, Acta Mater., 2017, Vol. 128, pp. 87-95CrossRef
84.
E. Chauvet, P. Kontis, E. A. Jagle, B. Gault, D. Raabe, C. Tassin, J.-J. Blandin, R. Dendievel, B. Vayre, S. Abed, and G. Martin, Acta Mater., 2018, Vol. 142, pp. 82-94CrossRef
85.
E. A. Jagle, Z. Sheng, L. Wu, L. Lu, J. Risse, A. Weisheit, and D. Raabe, JOM, 2016, Vol. 68, pp. 943-949CrossRef
86.
G. H. Cao, T. Y. Sun, C. H. Wang, X. Li, M. Liu, Z. X. Zhang, P. F. Hu, A. M. Russell, R. Scheneider, D. Gerthsen, Z. J. Zhou, C. P. Li and G. F. Chen, Mater. Charact., 2018, Vol. 136, pp. 398-406CrossRef
87.
H. E. Helmer, C. Korner, and R. F. Singer, J. Mater. Res., 2014, Vol. 29, pp. 1987-1996CrossRef
88.
M. Ramsperger, R. F. Singer, and C. Korner, Metall. Mater. Trans. A, 2016, Vol. 47A, pp. 1469-1480CrossRef
89.
C. Li, R. White, X. Y. Fang, M. Weaver, Y. B. Guo, Mater. Sci. Eng. A, 2017, Vol. 705, pp. 20-31CrossRef
90.
K. Essa, R. Khan, H. Hassanin, M. M. Attallah, and R. Reed, Int. J. Adv. Manuf. Technol., 2016, Vol. 83, pp. 1835-1845CrossRef
91.
M. Bambach, I. Sizova, F. Silze, M. Schnik, J. Alloys Compd., 2018, Vol. 740, pp. 278-287CrossRef
92.
M. Ramsperger, L. M. Roncery, I. Lopez-Galilea, R. F. Singer, W. Theisen and C. Korner, Adv. Eng. Mater., 2005, Vol. 17, pp. 1486-1493CrossRef
93.
T. G. Vilaro, C. Colin, J. D. Barout, L. Naze and M. Sennour, Mater. Sci. Eng. A, 2012, Vol. 534, pp. 446-451CrossRef
94.
95.
P. Kanagarajah, F. Brenne, T. Niendorf and H. J. Maier, Mater. Sci. Eng. A, 2013, Vol. 588, pp. 188-195CrossRef
96.
K. Kunze, T. Etter, J. Grasslin, V. Shklover, Mater. Sci. Eng. A, 2015, Vol. 620, pp. 213-222CrossRef
97.
A. Krietcberg, V. Brailovski and S. Turenne, Mater. Sci. Eng. A, 2017, Vol. 689, pp. 1-10CrossRef
98.
G. Bi, C-N. Sun, H-C. Chen, F. L. Nag, C. C. K. Ma, Mat. Des., 2014, Vol. 60, pp. 401-408CrossRef
99.
E. R. Denlinger, J. C. Heigel, P. Michaleris and T. A. Palmer, J. Mater. Process. Technol., 2015, Vol. 215, pp. 123-131CrossRef
100.
Z. Wang, E. Denlinger, P. Michaleris, A. D. Stoica, D. Ma and A. M. Beese, Mater. Des., 2017 Vol. 113, pp. 169-177CrossRef
101.
M. M. Attallah, R. Jennings, X. Q. Wang, and L N. Carter, MRS Bull., 2016, Vol. 41, pp. 758-764CrossRef
102.
S. K. Everton, M. Hirsch, P. Stravroulakis, R. K. Leach, and A. T. Clare, Mater. Des., 2016, Vol. 95, pp. 431-445CrossRef
103.
M. Hirsch, R. Patel, W. Li, G. Guan, R. K. Leach, S. D. Sharples and A. T. Clare, Addit. Manuf., 2017, Vol. 13, pp. 135-142CrossRef
104.
A. Townsend, N. Senin, L. Blunt, R. K. Leach and J. S. Taylor, Precis. Eng., 2016, Vol. 46, pp. 34-47CrossRef
105.
M. Islam, T. Purtonen, H. Piili, A. Salminen and O. Nyrhila, Phys. Proc., 2013, Vol. 41, pp. 835-842CrossRef
106.
L. Song, W. Huang, X. Han and J. Mazumder, IEEE Trans. Ind. Electron., 2017, Vol. 64, pp. 633-642CrossRef
107.
National academics of Sciences, Engineering, and Medicine 2016, in Predictive Theoretical and Computational Approaches for Additive Manufacturing: Proceedings of a Workshop. The National Academics Press, Washington, DC. https://​doi.​org/​10.​17226/​23646
108.
M. Thomas, G. J. Baxter, and I. Todd, Acta Mater., 2016, Vol. 108, pp. 26-35CrossRef
109.
110.
T. M. Rodgers, J. D. Madison, and V. Tikare, Comput. Mater. Sci., 2017, Vol. 135, pp. 78-89CrossRef
111.
R. Acharya, J. A. Sharon and A. Staroselsky, Acta Mater., 2017, Vol. 124, pp. 360-371CrossRef
112.
H. L. Wei, J. Mazumder and T. DebRoy, Sci. Rep., 2015, Vol. 5, p. 16446CrossRef
113.
T. Mukherjee, W. Zhang and T. DebRoy, Comput. Mater. Sci., 2017, Vol. 126, pp. 360-372CrossRef
Metadaten
Titel
Additive Manufacturing of Nickel Superalloys: Opportunities for Innovation and Challenges Related to Qualification
verfasst von
S. S. Babu
N. Raghavan
J. Raplee
S. J. Foster
C. Frederick
M. Haines
R. Dinwiddie
M. K. Kirka
A. Plotkowski
Y. Lee
R. R. Dehoff
Publikationsdatum
01.06.2018
Verlag
Springer US
Erschienen in
Metallurgical and Materials Transactions A / Ausgabe 9/2018
Print ISSN: 1073-5623
Elektronische ISSN: 1543-1940
DOI
https://doi.org/10.1007/s11661-018-4702-4

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