论文信息 - Morphology and Crystallography of Thermoelastic γ' Cu-Al-Ni Martensite

Morphology and Crystallography of Thermoelastic γ' Cu-Al-Ni Martensite

Thermoelastic γ' Cu–14.2A1–4.3Ni (w/o) martensite has been studied using the techniques of electron microscopy and electron diffraction, in order to explain the morphology on a microscopic scale. A plane of ridge which is frequently observed in a typical “spear-like” martensite has been identified as (121)γ' twinning plane. Further it has been shown that each half divided by the plane of ridge is internally twinned on {121}γ', other than the (121)γ' plane and each internal twin is faulted on each basal plane. A new orientation relationship consistent with the morphology is proposed, that is (110)[11̄1̄]β1 //(121)[21̄0]γ', according to which the two halves divided by the plane of ridge can be regarded as variants of martensite as well as twins to each other. This feature can be satisfied only by the new orientation relationship. Twinning nature of “spear-like” martensite is also discussed.

K. Shimizu | K. Otsuka

[1] J. Christian,et al. The theory of transformations in metals and alloys , 2003 .

[2] K. Otsuka. Origin of Memory Effect in Cu-Al-Ni Alloy , 1971 .

[3] K. Shimizu,et al. Memory effect and thermoelastic martensite transformation in CuAlNi alloy , 1970 .

[4] K. Shimizu,et al. {10\bar12} Transformation Twins in Hexagonal Martensite , 1970 .

[5] M. Duggin. Further studies of martensitic transformations in gold-copper-zinc and copper-aluminium-nickel alloys , 1966 .

[6] M. Duggin,et al. The nature of the martensite transformation in a coppernickel-aluminium alloy , 1964 .

[7] H. Warlimont,et al. The electron-metallography and crystallography of copper-aluminum martensites , 1963 .

[8] W. Rachinger. A "super-elastic" single crystal calibration bar , 1958 .

[9] J. Mackenzie,et al. The crystallography of martensite transformations—IV body-centred cubic to orthorhombic transformations , 1957 .

[10] T. Read,et al. Cubic to Orthorhombic Diffusionless Phase Change— Experimental and Theoretical Studies of AuCd , 1955 .

[11] W. G. Burgers. On the process of transition of the cubic-body-centered modification into the hexagonal-close-packed modification of zirconium , 1934 .

[12] J. Mackenzie,et al. The crystallography of martensite transformations II , 1954 .

[13] M. Wechsler. O the Theory of the Formation of Martensite. , 1953 .

[14] Charles S. Barrett,et al. The Structure of Metals , 1904, Nature.