Hostname: page-component-586b7cd67f-2plfb Total loading time: 0 Render date: 2024-11-24T22:33:55.416Z Has data issue: false hasContentIssue false

In situ structural and texture analyses of monoclinic phase for polycrystalline Ni-rich Ti49.86Ni50.14 alloy from neutron diffraction data

Published online by Cambridge University Press:  29 February 2012

Husin Sitepu
Affiliation:
Crystallography Laboratory, Virginia Tech, Blacksburg, Virginia 24061, USA and Department of Physics, College of Science, Sultan Qaboos University, P.O. Box 36, Postal Code 123, Muscat, Oman

Abstract

Phase transformation temperatures of a polycrystalline Ni-rich Ti49.86Ni50.14 shape memory alloy were investigated using a differential scanning calorimeter. In situ structural and texture analyses of the monoclinic Ti49.86Ni50.14 were investigated using neutron powder diffractometer technique. Differential scanning calorimeter results showed that this Ni-rich alloy has a one-step cubic to monoclinic martensitic phase transformation on cooling and a one-step monoclinic to cubic transformation on heating. In situ high-resolution neutron powder diffraction data of the monoclinic phase from low temperatures to room temperature on heating are consistent with the differential scanning calorimeter’s heating results. In addition, the refined monoclinic crystal structure parameters for all neutron diffraction data sets agree satisfactorily with single-crystal X-ray diffraction results. The multiple-data-set capabilities of the GSAS Rietveld refinement program, with a generalized spherical-harmonics description was used successfully to extract the texture description directly from a simultaneous refinement using 52 time-of-flight monoclinic neutron diffraction patterns, taken from a polycrystalline sample held in 13 orientations inside the diffractometer.

Type
Technical Articles
Copyright
Copyright © Cambridge University Press 2008

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

Bunge, H.-J. (1982). Texture Analysis in Materials Science: Mathematical Methods (P. R. Morris, Trans.) (Butterworth–Heinemann, London).Google Scholar
Kudoh, Y., Tokonami, M., Miyazaki, S., and Otsuka, K. (1985). “Crystal Structure of the Martensite in Ti50.8Ni49.2 Alloy Analyzed by the Single Crystal X-ray Diffraction Method,” Acta Metall. AMETAR 10.1016/0001-6160(85)90128-2 33, 20492056.CrossRefGoogle Scholar
Larson, A. C. and Von Dreele, R. B. (2000). General Structure Analysis System (GSAS) (Report LAUR 86-748). Los Alamos, New Mexico: Los Alamos National Laboratory.Google Scholar
Lutterotti, L., Matthies, S., Wenk, H.-R., Schultz, A. S., and Richardson, J. W. Jr. (1997). “Combined Texture and Structure Analysis of Deformed Limestone from Time-of-flight Neutron Diffraction Spectra,” J. Appl. Phys. JAPIAU 10.1063/1.364220 81, 594600.CrossRefGoogle Scholar
Matthies, S., Wenk, H.-R., and Vinel, G. W. (1988). “Some Basic Concepts of Texture Analysis and Comparison of Three Methods to Calculate Orientation Distributions from Pole Figures,” J. Appl. Crystallogr. JACGAR 10.1107/S0021889888000275 21, 285304.CrossRefGoogle Scholar
Matthies, S., Lutterotti, L., and Wenk, H.-R. (1997). “Advances in Texture Analysis from Diffraction Spectra,” J. Appl. Crystallogr. JACGAR 10.1107/S0021889896006851 30, 3142.CrossRefGoogle Scholar
Michal, G. M., and Sinclair, R. (1981). “The Structure of Ti-Ni Martensite,” Acta Crystallogr. ACBCAR 10.1107/S0567740881007292 37, 18031807.CrossRefGoogle Scholar
Otsuka, K., and Ren, X. (2005). “Physical Metallurgy of Ti-Ni-based Shape Memory Alloys,” Prog. Mater. Sci. PRMSAQ 10.1016/j.pmatsci.2004.10.001 50, 511678.CrossRefGoogle Scholar
Popa, N. C. (1992). “Texture in Rietveld Refinement,” J. Appl. Crystallogr. JACGAR 10.1107/S0021889892004795 25, 611616.CrossRefGoogle Scholar
Sitepu, H. (2002). “Assessment of Preferred Orientation with Neutron Powder Diffraction Data,” J. Appl. Crystallogr. JACGAR 10.1107/S0021889801021537 35, 274277.CrossRefGoogle Scholar
Sitepu, H. (2003). “Use of Synchrotron Diffraction Data for Describing Crystal Structure and Crystallographic Phase Analysis of R-phase NiTi Shape Memory Alloy,” Textures Microstruct. TEMIDK 35, 185195.CrossRefGoogle Scholar
Sitepu, H. (2007). “Structural Refinement of Neutron Powder Diffraction Data of Two-stage Martensitic Phase Transformations in Ti50.75Ni47.75Fe1.50 Shape Memory Alloy,” Powder Diffr. PODIE2 10.1154/1.2754715 22, 209318.CrossRefGoogle Scholar
Sitepu, H., Schmahl, W. W., Allafi, J. K., Eggeler, G., Dlouhy, A., Toebbens, D. M., and Tovar, M. (2002a). “Neutron Diffraction Phase Analysis During Thermal Cycling of a Ni-rich NiTi Shape Memory Alloy Using the Rietveld Method,” Scr. Mater. SCMAF7 10.1016/S1359-6462(02)00032-5 46, 543548.CrossRefGoogle Scholar
Sitepu, H., Schmahl, W. W., and Von Dreele, R. B. (2002b). “Use of the Generalized Spherical Harmonic Model for Describing Crystallographic Texture in Polycrystalline NiTi Shape-memory Alloy with Time-of-flight Neutron Powder Diffraction Data,” Appl. Phys. A APAMFC 74, S1676S1678.CrossRefGoogle Scholar
Sitepu, H., Schmahl, W. W., and Stalick, J. K. (2002c). “Correction of Intensities for Preferred Orientation in Neutron-diffraction Data of NiTi Shape-memory Alloy Using the Generalized Spherical-harmonic Description,” Appl. Phys. A APAMFC 10.1007/s003390201840 74, S1719S1721.CrossRefGoogle Scholar
Sitepu, H., O’Connor, B. H., and Li, D. (2005). “Comparative Evaluation of the March and Generalized Spherical Harmonic Preferred Orientation Models Using X-ray Diffraction Data for Molybdite and Calcite Powders,” J. Appl. Crystallogr. JACGAR 10.1107/S0021889804031231 38, 158167.CrossRefGoogle Scholar
Volz, H. M., Vogel, S. C., Necker, C. T., Roberts, J. A., Lawson, A. C., Williams, D. J., Daemen, L. L., Lutterotti, L., and Pehl, J. (2006). “Rietveld Texture Analysis by Neutron Diffraction of Highly Absorbing Materials,” Adv. X-Ray Anal. AXRAAA 49, 156162.Google Scholar
Von Dreele, R. B. (1997). “Quantitative Texture Analysis by Rietveld Refinement,” J. Appl. Crystallogr. JACGAR 10.1107/S0021889897005918 30, 517525.CrossRefGoogle Scholar
Wang, F. E., Buehler, W. J., and Pickart, S. J. (1965). “Crystal Structure and a Unique “Martensitic” Transition of TiNi,” J. Appl. Phys. JAPIAU 10.1063/1.1702955 36, 32323239.CrossRefGoogle Scholar
Wenk, H.-R., Lutterotti, L., and Vogel, S. (2003). “Texture Analysis With the New HIPPO TOF Diffractometer,” Nucl. Instrum. Methods Phys. Res. A NIMAER 10.1016/j.nima.2003.05.001 515, 575588.CrossRefGoogle Scholar