Hostname: page-component-cd9895bd7-gbm5v Total loading time: 0 Render date: 2024-12-23T18:59:02.005Z Has data issue: false hasContentIssue false
  • English
  • Français

Particle size and microstrain measurement in ADI alloysa)

Published online by Cambridge University Press:  05 March 2012

Jorge L. Garin ,
Rodolfo L. Mannheim  and
Marco A. Soto
Jorge L. Garin*
Affiliation:
Department of Metallurgical Engineering, Universidad de Santiago de Chile, Casilla 10233, Santiago, Chile
Rodolfo L. Mannheim
Affiliation:
Department of Metallurgical Engineering, Universidad de Santiago de Chile, Casilla 10233, Santiago, Chile
Marco A. Soto
Affiliation:
Department of Metallurgical Engineering, Universidad de Santiago de Chile, Casilla 10233, Santiago, Chile
*
b)Electronic mail: [email protected]
Get access Rights & Permissions [Opens in a new window]

Abstract

In this study we deal with the determination of crystallite-size distribution and microstrain measurement in austempered ductile irons (ADI) subjected to cold deformation, by means of x-ray diffraction line broadening. The deformation process imposed on the material yields the formation of microstrain and crystallite size domains within each grain, which are somehow related to the mechanical behavior of the alloy. Three series of samples were cold-worked from 2.5% to 20.0% of thickness reduction in order to determine the domain size and microstrain induced in the material, in terms of the original thickness of the castings and the percentage of cold work. The x-ray diffraction line-broadening effects were analyzed by means of the Warren–Averbach method, which allowed the separation of size and strain parameters. The particle size distribution resulted in an average column length in the range of 15.7–24.9 nm in the ferrite phase, while the austenite phase showed values varying between 13.4 and 36.3 nm. On the other side, the overall root mean square strain varied from 0.000 85 to 0.003 93 for ferrite and from 0.000 65 to 0.004 38 for austenite. In all of the studied cases the average column length decreased with increasing deformation, while the initial thickness of the cast samples did not show any clear correlation with increasing deformation.

Keywords

crystallite size and microstrainaustempered ductile iron
Type
Technical Articles
Information
Powder Diffraction , Volume 17 , Issue 2 , June 2002 , pp. 119 - 124
Copyright
Copyright © Cambridge University Press 2005

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

Aranzabal, J., Gutiérrez, I., Rodríguez-Ibabe, J. M., and Urcola, J. J. (1997). “Influence of the amount and morphology of retained austenite on the mechanical properties of an austempered ductile iron,” Metall. Mater. Trans. A MMTAEB 28A, 1143–1156. mma, MMTAEB CrossRefGoogle Scholar
Bayati, H., and Elliott, R. (1997). “Role of austenite in promoting ductility in an austempered ductile iron,” Mater. Sci. Technol. MSCTEP 13, 319–326. mtt, MSCTEP CrossRefGoogle Scholar
Cullity, B. D. (1978). Elements of X-Ray Diffraction, 2nd ed. (Addison-Wesley, Reading).Google Scholar
Garin, J. L., and Mannheim, R. L. (2000). “Microstructural characterization of ADI and AVI alloys by means of Rietveld analysis,” Z. Metallkd. ZEMTAE 91, 842–847. zem, ZEMTAE Google Scholar
Hill, R. J., and Howard, C. J. (1987). “Quantitative phase analysis from neutron powder diffraction data using the Rietveld method,” J. Appl. Crystallogr. JACGAR 20, 467–474. acr, JACGAR CrossRefGoogle Scholar
Hill, R. J. (1991). “Expanded use of the Rietveld method in studies of phase abundance in multiphase mixtures,” Powder Diffr. PODIE2 6, 74–77. pdj, PODIE2 Google Scholar
Jenkins, R., and Snyder, R. L. (1996). X-Ray Powder Diffractometry (Wiley, New York).Google Scholar
Kirgin, K. H. (1998). “Looking forward: ductile Iron’s ‘roar’ into the 21st century,” Mod. Cast. MOCAB5 88, 63–66. 9tk, MOCAB5 Google Scholar
Nusinovici, J., and Rehfeldt-Oskierski, A. (1990). “DIFFRAC-AT search/match and profile fitting programs,” Collected Abstracts, IUCr Powder Diffraction Satellite Meeting, Toulouse, France, 16–19 July 1990, pp. 315–316.Google Scholar
Rao, P. P., and Putatunda, S. K. (1997). “Influence of microstructure on fracture-toughness of austempered ductile iron,” Metall. Mater. Trans. A MMTAEB 28, 1457–1470. mma, MMTAEB Google Scholar
Rao, S., and Houska, C. R. (1986). “X-ray particle-size broadening,” Acta Crystallogr., Sect. A: Found. Crystallogr. ACACEQ 42, 6–13. acf, ACACEQ Google Scholar
Sigma-C GmbH (1991). “WIN-CRYSIZE Crystallite size and microstrain,” Update Version 1.03, Rosenheimer Landstr. 74, Mu¨nchen.Google Scholar
Thompson, P., Cox, D. E., and Hastings, J. B. (1987). “Rietveld refinement of Debye–Scherrer synchrotron X-ray data from Al2O3,” J. Appl. Crystallogr. JACGAR 20, 79–83. acr, JACGAR Google Scholar
Van Berkum, J. G. M., Vermeulen, A. C., Delhez, R., de Keijser, T. H., and Mittemeijer, E. J. (1993). “Fourier methods for separation of size and strain broadening,” Mater. Sci. Forum MSFOEP 133–136, 77–82. msf, MSFOEP CrossRefGoogle Scholar
Van Berkum, J. G. M., Vermeulen, A. C., Delhez, R., Dkeijser, T. H., and Mittemeijer, E. J. (1994). “Applicabilities of the Warren–Averbach analysis and an alternative analysis for separation of size and strain broadening,” J. Appl. Crystallogr. JACGAR 27, 345–357. acr, JACGAR CrossRefGoogle Scholar
Van Berkum, J. G. M., Delhez, R., Dkeijser, T. H., and Mittemeijer, E. J. (1996). “Diffraction-line broadening due to strain fields in materials; fundamental aspects and methods of analysis,” Acta Crystallog. Sect. A: Found. Crystallogr. ACACEQ 52, 730–747. acf, ACACEQ CrossRefGoogle Scholar
Waander, F. B., Vorster, S. W., and Vorster, M. J. (1998). “Some mechanical properties of austempered ductile iron,” Hyperfine Interact. HYINDN 112, 143–146. hfi, HYINDN CrossRefGoogle Scholar
Warren, B. E. (1969). X-Ray Diffraction (Addison-Wesley, Reading).Google Scholar
Warren, B. E., and Averbach, B. L. (1950). “The effect of cold-work distortion on x-ray patterns,” J. Appl. Phys. JAPIAU 21, 595–599. jap, JAPIAU Google Scholar
Warren, B. E., and Averbach, B. L. (1952). “The separation of cold work distortion and particle size broadening in x-ray patterns,” J. Appl. Phys. JAPIAU 23, 497. jap, JAPIAU CrossRefGoogle Scholar
Wen, D. C., and Lei, T. S. (1999). “The mechanical properties of a low-alloyed austempered ductile iron in the upper ausferrite region,” ISIJ Int. IINTEY 39 (5), 493–500. iit, IINTEY CrossRefGoogle Scholar
Young, R. A. (1996). The Rietveld Method (Oxford University Press, Oxford), reprinted, p. 292.Google Scholar
Young, R. A., Sakthivel, A., Moss, T. S., and Paiva-Santos, C. O. (1996). “Rietveld analysis of x-ray and neutron powder diffraction patterns,” Program DBWS-9411, Georgia Institute of Technology, Atlanta.Google Scholar
Yvon, K., Jeitschko, W., and Parthé, E. (1977). “LAZY-PULVERIX, a computer program, for calculating x-ray and neutron diffraction powder patterns,” J. Appl. Crystallogr. JACGAR 10, 73–74. acr, JACGAR CrossRefGoogle Scholar