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Erschienen in: Metallurgical and Materials Transactions A 7/2007

01.07.2007

In-Situ Observations on the Fracture Mechanism of Diffusion-Alloyed Ni-Containing Powder Metal Steels and a Proposed Method for Tensile Strength Improvement

verfasst von: M. W. Wu, K. S. Hwang, H. S. Huang

Erschienen in: Metallurgical and Materials Transactions A | Ausgabe 7/2007

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Abstract

The mechanical properties of Ni-containing powder metal (PM) steels are usually inferior to those of their wrought counterparts. The main problem is attributed to the non-uniform Ni distribution, in addition to the problems caused by porosity. The effects of this non-uniform alloying on the mechanical properties were investigated in this study using mini tensile bars that were made of diffusion-alloyed FD-0405 (Fe-4Ni-1.5Cu-0.5Mo-0.5C) powders. In-situ observations under a scanning electron microscope (SEM) were carried out during the tensile testing. The results indicated that the soft Ni-rich/C-lean area around the pore, which was identified as ferrite using electron backscattered diffraction (EBSD) analysis, was responsible for the failures. By adding Cr in the form of prealloyed powders, the distribution of Ni and C became more uniform, and the Ni-rich/C-lean ferrite was replaced by bainite and martensite. After sintering at 1250 °C for 1 hour, the tensile strength of the Fe-4Ni-1.5Cr-0.2Mo-0.5C and Fe-4Ni-3Cr-0.5Mo-0.5C reached 1178 and 1323 MPa, respectively, without employing any accelerated cooling system. These properties are higher than all those reported to date in the literature for sinter-hardened PM alloys that were rapidly cooled after sintering. This significant improvement was attributed to the homogeneous alloying, particularly due to the reduction of the repelling effect between Ni and C, as was explained through the thermodynamics analysis using the Thermo-Calc program.

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Fußnoten
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Literatur
1.
Zurück zum Zitat F. Thümmler and R. Oberacker: Introduction to PM, The Institute of Materials, London, UK, 1993, pp. 255–58 F. Thümmler and R. Oberacker: Introduction to PM, The Institute of Materials, London, UK, 1993, pp. 255–58
2.
Zurück zum Zitat N. Chawla, X. Deng: Mater. Sci. Eng., 2005, vol. 390A, pp. 98–112 N. Chawla, X. Deng: Mater. Sci. Eng., 2005, vol. 390A, pp. 98–112
3.
Zurück zum Zitat W.A. Spitzig, R.E. Semlser, O. Richmond: Acta Metall., 1988, vol. 36 (5), pp. 1201–11CrossRef W.A. Spitzig, R.E. Semlser, O. Richmond: Acta Metall., 1988, vol. 36 (5), pp. 1201–11CrossRef
4.
Zurück zum Zitat R.J. Bourcier, D.A. Koss, R.E. Smelser, O. Richmond: Acta Metall., 1986, vol. 34 (12), pp. 2443–53CrossRef R.J. Bourcier, D.A. Koss, R.E. Smelser, O. Richmond: Acta Metall., 1986, vol. 34 (12), pp. 2443–53CrossRef
5.
Zurück zum Zitat K.M. Vedula, R.W. Heckel: in Modem Developments in Powder Metallurgy, H.H. Hausner, H.W. Antes, G.D. Smith, eds., Metal Powder Industries Federation, Princeton, NJ, 1981, vol. 12, pp. 759–77 K.M. Vedula, R.W. Heckel: in Modem Developments in Powder Metallurgy, H.H. Hausner, H.W. Antes, G.D. Smith, eds., Metal Powder Industries Federation, Princeton, NJ, 1981, vol. 12, pp. 759–77
6.
Zurück zum Zitat T. Marcu, A. Molinari, G. Straffelini, S. Berg: Powder Metall., 2005, vol. 48 (2), pp. 139–43CrossRef T. Marcu, A. Molinari, G. Straffelini, S. Berg: Powder Metall., 2005, vol. 48 (2), pp. 139–43CrossRef
7.
Zurück zum Zitat M. Hanada, N. Motooka, and T. Honda: Advances in Powder Metallurgy and Particulate Materials, compiled by J.M. Capus and R.M. German, MPIF, Princeton, NJ, 1992, vol. 5, pp. 215–26 M. Hanada, N. Motooka, and T. Honda: Advances in Powder Metallurgy and Particulate Materials, compiled by J.M. Capus and R.M. German, MPIF, Princeton, NJ, 1992, vol. 5, pp. 215–26
8.
Zurück zum Zitat R. J. Causton: Advances in Powder Metallurgy and Particulate Materials, compiled by T.M. Cadle and K.S. Narasimhan, MPIF, Princeton, NJ, 1996, vol. 4, part 13, pp. 391–412 R. J. Causton: Advances in Powder Metallurgy and Particulate Materials, compiled by T.M. Cadle and K.S. Narasimhan, MPIF, Princeton, NJ, 1996, vol. 4, part 13, pp. 391–412
9.
Zurück zum Zitat M. Khaleghi, R. Haynes: Powder Metall., 1985, vol. 28 (4), pp. 217–23 M. Khaleghi, R. Haynes: Powder Metall., 1985, vol. 28 (4), pp. 217–23
10.
Zurück zum Zitat Materials Standards for P/M Structural Parts, Metal Powder Industries Federation, Princeton, NJ, 2003, pp. 42–49 Materials Standards for P/M Structural Parts, Metal Powder Industries Federation, Princeton, NJ, 2003, pp. 42–49
11.
Zurück zum Zitat M.W. Wu, K.S. Hwang, H.S. Huang, K.S. Narasimhan: Metall. Mater. Trans. A, 2006, vol. 37A, pp. 2559–68CrossRef M.W. Wu, K.S. Hwang, H.S. Huang, K.S. Narasimhan: Metall. Mater. Trans. A, 2006, vol. 37A, pp. 2559–68CrossRef
12.
Zurück zum Zitat S. Carabajar, C. Verdu, R. Fougeres: Mater. Sci. Eng., 1997, vol. 232A, pp. 80–87 S. Carabajar, C. Verdu, R. Fougeres: Mater. Sci. Eng., 1997, vol. 232A, pp. 80–87
13.
Zurück zum Zitat N. Chawla, T.F. Murphy, K.S. Narasimhan, M. Koopman, K.K. Chawla: Mater. Sci. Eng., 2001, vol. 308A, pp. 180–88 N. Chawla, T.F. Murphy, K.S. Narasimhan, M. Koopman, K.K. Chawla: Mater. Sci. Eng., 2001, vol. 308A, pp. 180–88
14.
Zurück zum Zitat E. Dudrova, M. Kabatova, M. Kupkova: Kov. Mater. 2002, vol. 40, pp. 24–33 E. Dudrova, M. Kabatova, M. Kupkova: Kov. Mater. 2002, vol. 40, pp. 24–33
15.
Zurück zum Zitat S.J. Polasik, J.J. Williams, N. Chawla: Metall. Mater. Trans. A, 2002, vol. 33A, pp. 73–81CrossRef S.J. Polasik, J.J. Williams, N. Chawla: Metall. Mater. Trans. A, 2002, vol. 33A, pp. 73–81CrossRef
16.
Zurück zum Zitat S. Carabajar, C. Verdu, A. Hamel, R. Fougeres: Mater. Sci. Eng., 1998, vol. 257A, pp. 225–34 S. Carabajar, C. Verdu, A. Hamel, R. Fougeres: Mater. Sci. Eng., 1998, vol. 257A, pp. 225–34
17.
Zurück zum Zitat N. Chawla, S. Polasik, K.S. Narasimhan, T. Murphy, M. Koopman, K.K. Chawla: Int. J. Powder Metall., 2001, vol. 37 (3), pp. 49–57 N. Chawla, S. Polasik, K.S. Narasimhan, T. Murphy, M. Koopman, K.K. Chawla: Int. J. Powder Metall., 2001, vol. 37 (3), pp. 49–57
18.
Zurück zum Zitat B.A. Gething, D.F. Heaney, D.A. Koss, T.J. Mueller: Mater. Sci. Eng., 2005, vol. 390A, pp. 19–26 B.A. Gething, D.F. Heaney, D.A. Koss, T.J. Mueller: Mater. Sci. Eng., 2005, vol. 390A, pp. 19–26
19.
Zurück zum Zitat Z.R. He, G.X. Lin, H.A. Chen: Mater. Sci. Eng., 2001, vols. 319A–321A, pp. 312–15 Z.R. He, G.X. Lin, H.A. Chen: Mater. Sci. Eng., 2001, vols. 319A–321A, pp. 312–15
20.
Zurück zum Zitat M. Dollar, I.M. Bernstein, A.W. Thompson: Acta Metall., 1988, vol. 36 (2), pp. 311–20CrossRef M. Dollar, I.M. Bernstein, A.W. Thompson: Acta Metall., 1988, vol. 36 (2), pp. 311–20CrossRef
21.
Zurück zum Zitat M.W. Wu, K.S. Hwang: Metall. Mater. Trans. A, 2006, vol. 37A, pp. 3577–85 M.W. Wu, K.S. Hwang: Metall. Mater. Trans. A, 2006, vol. 37A, pp. 3577–85
22.
Zurück zum Zitat S.T. Campbell, T. Singh, and T.F. Stephenson: Advances in Powder Metallurgy and Particulate Materials, compiled by W.B. James and R.A. Chernenkoff, MPIF, Princeton, NJ, 2004, part 7, pp. 105–15 S.T. Campbell, T. Singh, and T.F. Stephenson: Advances in Powder Metallurgy and Particulate Materials, compiled by W.B. James and R.A. Chernenkoff, MPIF, Princeton, NJ, 2004, part 7, pp. 105–15
23.
Zurück zum Zitat H. Danninger, D. Spoljaric, B. Weiss: Int. J. Powder Metall., 1997, vol. 33 (4), pp. 43–53 H. Danninger, D. Spoljaric, B. Weiss: Int. J. Powder Metall., 1997, vol. 33 (4), pp. 43–53
24.
Zurück zum Zitat W.F. Smith: Structure and Properties of Engineering Alloys, 2nd ed., McGraw-Hill Co., New York, NY, 1993, pp. 136–37 W.F. Smith: Structure and Properties of Engineering Alloys, 2nd ed., McGraw-Hill Co., New York, NY, 1993, pp. 136–37
25.
Zurück zum Zitat A. Moser, A. Legat: Hart. Techn. Mitt., 1969, vol. 24 (2), pp. 100–05. A. Moser, A. Legat: Hart. Techn. Mitt., 1969, vol. 24 (2), pp. 100–05.
Metadaten
Titel
In-Situ Observations on the Fracture Mechanism of Diffusion-Alloyed Ni-Containing Powder Metal Steels and a Proposed Method for Tensile Strength Improvement
verfasst von
M. W. Wu
K. S. Hwang
H. S. Huang
Publikationsdatum
01.07.2007
Erschienen in
Metallurgical and Materials Transactions A / Ausgabe 7/2007
Print ISSN: 1073-5623
Elektronische ISSN: 1543-1940
DOI
https://doi.org/10.1007/s11661-007-9201-y

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