| Numéro |
J. Phys. Colloques
Volume 43, Numéro C4, Décembre 1982
ICOMAT-82International Conference on Martensitic Transformations |
|
|---|---|---|
| Page(s) | C4-641 - C4-645 | |
| DOI | https://doi.org/10.1051/jphyscol:19824103 | |
International Conference on Martensitic Transformations
J. Phys. Colloques 43 (1982) C4-641-C4-645
DOI: 10.1051/jphyscol:19824103
DEFORMATION BEHAVIOUR OF SINGLE CRYSTAL OF Cu-Al MARTENSITIC ALLOYS
A. Gyobu1, K. Enami2, A. Nagasawa3 et S. Nenno21 Department of Mechanical Engineering, Niihama Technical College, Ehime, Japan
2 Department of Materials Science and Engineering, Osaka University, Suita, Osaka, Japan
3 Department of Physics, Nara Women's University, Nara, Japan
Abstract
Deformation behaviour and stress-induced martensite-martensite transformation of binary Cu-Al β-martensitic alloys were investigated by tensile and compression test, X-ray analysis and electronmicroscopy. Three kinds of Cu-Al alloys having 18R(β'1), 18R+2H, and 2H(β'1) structures in the initial as-quenched state, respectively, were examined. In the specimen with <001>β tensile axis, it was found that deformation proceeds by Lüders deformation. That is, narrow band appears at first and then this "deformation" band propagates along the tensile axis. It was found that in the deformation band region, martensite-martensite transformation, β'1 or γ'1 → α'1(DO22) occurs, by using precession X-ray method. It was also found that γ'1 martensite transformed directly to α'1 martensite without passing the successive γ'1 to β'1 to α'1 transformation like in the Cu-Al-Ni alloys. When the martensite-martensite transformation took place along the whole length of the tensile specimen, single crystal of α'1 martensite was obtained and this α'1 single crystal was stable upon unloading the tensile stress. When the α'1 single crystal specimen which was produced by tensile deformation of the specimen with 2H+18R mixture along [001]β direction, was compressed along [00[MATH]]β (=[00[MATH]]DO22) direction, the reverse transformation α'1 to γ'1 was found to occur without forming β'1 martensite.