Hostname: page-component-586b7cd67f-rcrh6 Total loading time: 0 Render date: 2024-11-23T09:05:30.507Z Has data issue: false hasContentIssue false

Residual stress and strain-free lattice-parameter depth profiles in a γ′-Fe4N1-x layer on an α-Fe substrate measured by x-ray diffraction stress analysis at constant information depth

Published online by Cambridge University Press:  31 January 2011

M. Wohlschlögel
Affiliation:
Max Planck Institute for Metals Research, D-70569 Stuttgart, Germany
U. Welzel*
Affiliation:
Max Planck Institute for Metals Research, D-70569 Stuttgart, Germany
E.J. Mittemeijer
Affiliation:
Max Planck Institute for Metals Research, D-70569 Stuttgart, Germany
*
a) Address all correspondence to this author. e-mail: [email protected]
Get access

Abstract

The residual stress and lattice-parameter depth profiles in a γ′-Fe4N1-x layer (6-μm thickness) grown on top of an α-Fe substrate were investigated using x-ray diffraction stress analysis at constant penetration depths. Three different reflections (220, 311, and 222) were recorded at six different penetration depths using three different wavelengths. At each penetration depth, x-ray diffraction stress analysis was performed on the basis of the sin2ψ method. As a result, the residual-stress depth profile was obtained from the measured lattice strains. The lattice spacings measured in the strain-free direction were used to determine the (strain-free) lattice-parameter depth profile. The nitrogen-concentration depth profile in the layer was calculated by applying a relationship between the (strain-free) γ′ lattice parameter and the nitrogen concentration. It was found that the strain-free lattice-parameter depth profile as derived from the 311 reflections is best compatible with nitrogen concentrations at the surface and at the γ′/α interface as predicted on the basis of local thermodynamic equilibrium. It could be shown that the 311 reflection is most suitable for the analysis of lattice-parameter and residual stress depth profiles because the corresponding x-ray elastic constants exhibit the least sensitivity to the type of and changes in grain interaction. The depth-dependence of the grain interaction could be revealed. It was found that the grain interaction changes from Voigt-type near the surface to Reuss-type at the layer/substrate interface.

Type
Articles
Copyright
Copyright © Materials Research Society 2009

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1Knerr, C.H.Rose, T.C. and Filkowski, J.H.: Gas nitriding, in ASM Handbook, vol. 4, edited by Lampman, S.R. and Zorc, T.B. (ASM, 1991), p. 387.Google Scholar
2Jack, K.H.: Binary and ternary interstitial alloys. I. The ironnitrogen system: The structures of Fe4N and Fe2N. Proc. R. Soc. London, Ser. A 195, 34 (1948).Google Scholar
3Jacobs, H.Rechenbach, D. and Zachwieja, U.: Structure determination of γ-Fe4N and ε-Fe3N. J. Alloys Compd. 227, 10 (1995).CrossRefGoogle Scholar
4Kooi, B.J.Somers, M.A.J. and Mittemeijer, E.J.: An evaluation of the Fe-N phase diagram considering long-range order of N atoms in γ-Fe4N1-x and ε-Fe2N1-z. Metall. Mater. Trans. A 27, 1063 (1996).Google Scholar
5Wriedt, H.A.Gokcen, N.A. and Nafziger, R.H.: The Fe-N (ironnitrogen) system. Bull. Alloy Phase Diagr. 8, 355 (1987).Google Scholar
6Mittemeijer, E.J. and Somers, M.A.J.: Thermodynamics, kinetics, and process control of nitriding. Surf. Eng. 13, 483 (1997).Google Scholar
7Coey, J.M.D. and Smith, P.A.I.: Magnetic nitrides. J. Magn. Magn. Mater. 200, 405 (1999).Google Scholar
8Borsa, D.M.Grachev, S.Boerma, D.O. and Kerssemakers, W.J.: High-quality epitaxial iron nitride films grown by gas-assisted molecular-beam epitaxy. Appl. Phys. Lett. 79, 994 (2001).Google Scholar
9Costa-Krämer, J.L., Borsa, D.M.García-Martín, J.M., Martín-González, M.S., Boerma, D.O. and Briones, F.: Structure and magnetism of single-phase epitaxial γ-Fe4N. Phys. Rev. B: Condens. Matter 69, 144402 (2004).Google Scholar
10Easton, E. Bradley, Buhrmester, Th., and Dahn, J.R.: Preparation and characterization of sputtered Fe1-xNx films. Thin Solid Films 493, 60 (2005).Google Scholar
11Gressmann, T.Wohlschlögel, M., Shang, S.Welzel, U.Leineweber, A.Mittemeijer, E.J. and Liu, Z-K.: Elastic anisotropy of γ-Fe4N and elastic grain interaction in γ-Fe4N1-y layers on a-Fe: First-principles calculations and diffraction stress measurements. Acta Mater. 55, 5833 (2007).Google Scholar
12Rozendaal, H.C.F.Mittemeijer, E.J.Colijn, P.F. and van, P.J.der Schaaf: The development of nitrogen concentration profiles on nitriding iron. Metall. Trans. A 14, 395 (1983).Google Scholar
13Somers, M.A.J. and Mittemeijer, E.J.: Layer-growth kinetics on gaseous nitriding of pure iron: Evaluation of diffusion coefficients for nitrogen in iron nitrides. Metall. Mater. Trans. A 26, 57 (1995).Google Scholar
14Liapina, T.Leineweber, A. and Mittemeijer, E.J.: Phase transformations in iron-nitride compound layers upon low-temperature annealing: Diffusion kinetics of nitrogen in ε and γ-iron nitrides. Metall. Mater. Trans. A 37, 319 (2006).CrossRefGoogle Scholar
15Schaaf, P.: Laser nitriding of metals. Prog. Mater. Sci. 47, 1 (2002).Google Scholar
16Wohlschlögel, M., Welzel, U. and Mittemeijer, E.J.: Unexpected formation of ε-Fe3N1+x by gas nitriding of a-Fe thin films. Appl. Phys. Lett. 91, 141901 (2007).Google Scholar
17Somers, M.A.J. and Mittemeijer, E.J.: Development and relaxation of stress in surface layers; Composition and residual stress profiles in γ-Fe4N1-x layers on a-Fe substrates. Metall. Trans. A 21, 189 (1990).Google Scholar
18Somers, M.A.J. and Mittemeijer, E.J.: Phase transformations and stress relaxation in γ-Fe4N1-x surface layers during oxidation. Metall. Trans. A 21, 901 (1990).Google Scholar
19Macherauch, E. and Müller, P.: The sin2ψ method of x-ray diffraction stress analysis. Z. Angew. Phys. 13, 305 (1961).Google Scholar
20Welzel, U. and Mittemeijer, E.J.: Diffraction stress analysis of macroscopically elastically anisotropic specimens: On the concepts of diffraction elastic constants and stress factors. J. Appl. Phys. 93, 9001 (2003).Google Scholar
21Welzel, U.Ligot, J.Lamparter, P.Vermeulen, A.C. and Mittemeijer, E.J.: Stress analysis of polycrystalline thin films and surface regions by x-ray diffraction. J. Appl. Cryst. 38, 1 (2005).Google Scholar
22Voigt, W.: Textbook of Crystal Physics. (Teubner, Leipzig, 1910).Google Scholar
23Reuss, A.: Calculation of the yield stress of solid solutions based on the plasticity condition for single crystals. Z. Angew. Math. Mech. 9, 49 (1929).Google Scholar
24Neerfeld, H.: On the calculation of stress from x-ray diffraction strain measurements. Mitt. K.-Wilh.-. Inst. Eisenforschg. 24, 61 (1942).Google Scholar
25Hill, R.: The elastic behaviour of a crystalline aggregate. Proc. Phys. Soc. London, Sect. A 65, 349 (1952).Google Scholar
26SAE: Report No. HS-784, Residual Stress Measurement by X-Ray Diffraction, 2003.Google Scholar
27Ricardo, C.L. Azanza, D'Incau, M., and Scardi, P.: Revision and extension of the standard laboratory technique for x-ray diffraction measurement of residual stress gradients. J. Appl. Cryst. 40, 675 (2007).Google Scholar
28Kämpfe, A., Eigenmann, B. and Löhe, D.: Comparative application of measuring techniques for x-ray analysis of grinding residual stresses in Al2O3 and AlN. Z. Metallk. 91, 967 (2000).Google Scholar
29Behnken, H. and Hauk, V.: Determination of steep stress gradients by x-ray diffraction—Results of a joint investigation. Mater. Sci. Eng., A 300, 41 (2001).Google Scholar
30Predecki, P.Ballard, B. and Zhu, X.: Proposed methods for depth profiling of residual stresses using grazing incidence x-ray diffraction (GIXD). Adv. X-Ray Anal. 36, 237 (1993).Google Scholar
31Acker, K. van, Buyser, L. de, Celis, J.P. and Houtte, P. van: Characterization of thin nickel electrocoatings by the lowincident-beam-angle diffraction method. J. Appl. Cryst. 27, 56 (1994).Google Scholar
32Genzel, Ch.: X-ray stress gradient analysis in thin layers—Problems and attempts at their solution. Phys. Status Solidi A 159, 283 (1997).Google Scholar
33Genzel, C.: X-ray residual stress analysis in thin films under grazing incidence—Basic aspects and applications. Mater. Sci. Technol. 21, 10 (2005).CrossRefGoogle Scholar
34Structural and Residual Stress Analysis by Nondestructive Methods, edited by Hauk, V. (Elsevier, Amsterdam, 1997).Google Scholar
35Bein, S.Calvez, C. Le, and Lebrun, J-L.: Determination of stress gradients by x-ray diffraction: Comparison of different methods and applications. Z. Metallkd. 89, 289 (1998).Google Scholar
36Skrzypek, S.J.Baczmanski, A.Ratuszek, W. and Kusior, E.: New approach to stress analysis based on grazing-incidence x-ray diffraction. J. Appl. Crystallogr. 34, 427 (2001).Google Scholar
37Kumar, A.Welzel, U. and Mittemeijer, E.J.: A method for the non-destructive analysis of gradients of mechanical stresses by x-ray diffraction measurements at fixed penetration/information depths. J. Appl. Crystallogr. 39, 633 (2006).CrossRefGoogle Scholar
38Serruys, W.Houtte, P. van, and Aernoudt, E.: X-ray measurement of residual stresses in textured materials with the aid of orientation distribution functions, in Residual Stresses in Science and Technology, edited by Macherauch, E. and Hauk, V. (Deutsche Gesellschaft fü r Metallkunde, Oberursel, 1987).Google Scholar
39Serruys, W.Langouche, F.Houtte, P. van, and Aernoudt, E.: Calculation of x-ray elastic constants in isotropic and textured materials, in Proceedings of ICRS 2, edited by Beck, G.Denis, S. and Simon, A. (Elsevier Applied Science, London, 1989), p. 166.Google Scholar
40Welzel, U.Leoni, M. and Mittemeijer, E.J.: Diffraction elastic constants and stress factors; Grain interaction and stress in macroscopically elastically anisotropic solids: The case of thin films, in Diffraction Analysis of the Microstructure of Materials, edited by Mittemeijer, E.J. and Scardi, P. (Springer, Berlin, 2004), p. 363.Google Scholar
41Wohlschlögel, M., Baumann, W.Welzel, U. and Mittemeijer, E.J.: Determination of depth gradients of grain interaction and stress in Cu thin films. J. Appl. Crystallogr. 41, 1067 (2008).Google Scholar
42Kumar, A.Welzel, U. and Mittemeijer, E.J.: Depth dependence of elastic grain interaction and mechanical stress: Analysis by x-ray diffraction measurements at fixed penetration/information depths. J. Appl. Phys. 100, 114904 (2006).Google Scholar
43Leverenz, T.Eigenmann, B. and Macherauch, E.: The sectioned polynomial method for non-destructive determination of residual stress states in machined ceramic materials with steep subsurface gradients. Z. Metallkd. 87, 616 (1996).Google Scholar
44Delhez, R.Keijser, Th.H. de, and Mittemeijer, E.J.: Role of x-ray diffraction analysis in surface engineering: Investigation of microstructure of nitrided iron and steels. Surf. Eng. 3, 331 (1987).Google Scholar
45Colijn, P.F.Mittemeijer, E.J. and Rozendaal, H.C.F.: Light-microscopical analysis of nitrided or nitrocarburized iron and steels. Z. Metallkd. 74, 620 (1983).Google Scholar
46Wells, A.: Metallographic analysis of compound layers on ferritic nitrocarburized plain low carbon steel. J. Mater. Sci. 20, 2439 (1985).Google Scholar
47Somers, M.A.J. and Mittemeijer, E.J.: Formation and growth of compound layer on nitrocarburizing iron: Kinetics and microstructural evolution. Surf. Eng. 3, 123 (1987).Google Scholar
48Creagh, D.C.: X-ray absorption spectra, in International Tables for Crystallography, vol. C, edited by Prince, E. (Kluwer, Dordrecht, 2004), p. 213.Google Scholar
49Chantler, C.T.Olsen, K.Dragoset, R.A.Chang, J.Kishore, A.R.Kotochigova, S.A. and Zucker, D.S.: X-ray from factor, attenuation, and scattering tables. Ver. 2.1. (National Institute of Standards and Technology, Gaithersburg, MD, 2005). Available at: http://physics.nist.gov/ffast. Accessed February 27, 2008.Google Scholar
50Wohlschlögel, M., Schülli, T.U., Lantz, B. and Welzel, U.: Application of a single-reflection collimating multilayer optic for x-ray diffraction experiments employing parallel-beam geometry. J. Appl. Crystallogr. 41, 124 (2008).Google Scholar
51Knapp, M.Baehtz, C.Ehrenberg, H. and Fuess, H.: The synchrotron powder diffractometer at beamline B2 at HASYLAB/DESY: Status and capabilities. J. Synchrotron Radiat. 11, 328 (2004).Google Scholar
52Sonneveld, E.J.Delhez, R.Keijser, Th.H. De, and Mittemeijer, E.J.: Quality of unravelling of experimenal diffraction patterns with artificially varied overlap. Mater. Sci. Forum 79–82, 85 (1991).Google Scholar
53Welzel, U.Lamparter, P.Leoni, M. and Mittemeijer, E.J.: Stress and diffusion in Nb-W bilayers. Mater. Sci. Forum 347–349, 405 (2000).Google Scholar
54Somers, M.A.J.Pers, N.M. van der, Schalkoord, D. and E.J. Mittemeijer: Dependence of the lattice parameter of γ iron nitride, Fe4N1-x, on nitrogen content; Accuracy of the nitrogen absorption data. Metall. Trans. A 20, 1533 (1989).Google Scholar
55Touloukian, Y.S.Kirby, R.K.Taylor, R.E. and Desai, P.D.: Thermal Expansion, Metallic Elements and Alloys (IFI/Plenum, New York, 1975).Google Scholar
56Welzel, U.Leoni, M. and Mittemeijer, E.J.: The determination of stresses in thin films; Modelling elastic grain interaction. Philos. Mag. 83, 603 (2003).Google Scholar