Deformation modes of quenched β Ti–16∼27%V alloys are investigated in compressive and tensile tests as a function of crystallographic orientation and deformation temperature. The {332} twinning takes place in the low vanadium content alloys. By analysing the twinning systems appearing in compressive and tensile tests, the polarization of twinning shear is confirmed to occur in the {332} twinning. The {332} twinning is suppressed by aging or oxygen addition. It is suggested that the formation of the {332} twinning is due to the instability of the β phase of Ti–V alloys containing some interstitial impurity atoms. On the other hand, deformation occurs by slip in the alloys with high content of V. These alloys exhibit an asymmetry of both the yield stress and the slip plane, the degree of asymmetry being larger at 77 K than at 300 K.

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The α₁(fct,c⁄a>1)\ ightleftarrowsα₂(fct,c⁄a<1) and α₂\ ightleftarrowsβ(fcc) phase transformations and the shape memory effect in indium-rich lead alloys were studied by means of the X-ray diffraction method supplemented by metallographic observations. The alloys containing 12–15 at%Pb exhibit a transformation from the α₂(fct) phase to the α₁(fct) phase by way of an intermediate phase on cooling. The metastable intermediate phase (m phase) has a face-centred orthorhombic structure and is observed on both cooling and heating. It is shown that the conventional α₁\ ightleftarrowsα₂ transformation should be described as the α₁\ ightleftarrowsm\ ightleftarrowsα₂ transformation. The alloys containing 30–36 at%Pb exhibit a transformation from the β(fcc) phase to the a₂(fct) phase on cooling. Surfaces of these m- and α₂-phase alloys show a banded relief structure due to {110} transformation twinning, and the banded structure disappears completely above the transformation temperature. The m\ ightleftarrowsα₂ and α₂\ ightleftarrowsβ transformations are diffusionless and take place by a mechanism involving macroscopic cooperative movements of atoms. The mechanism of these phase transformations is described in terms of the soft phonon mode, considering that one phonon mode corresponds to one cooperative movement of atoms. A remarkable shape memory effect is observed in the reverse transformation on heating. Its mechanism is discussed on the basis of the crystallographic reversibility of these transformations.

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Internal friction was measured at about 550 Hz in the temperature range between 160 K and 350 K for austenitic stainless steel subjected to hydrogen charging and plastic deformation. A hydrogen-induced characteristic peak was found at 300 K for both annealed and deformed specimens of all the materials used; SUS 310S, SUS 316 and SUS 304. Plastic deformation did not alter its height and shape at all, but brought about two distinct sub-peaks at 330 K and 230 K. The main peak at 300 K is attributable to the Snoek ordering of hydrogen atom-pairs in the FCC alloy steels, being independent of dislocations and other defects produced by plastic deformation. The 330 K sub-peak was observed for all deformed specimens in both cases of prestraining and post-straining. It may be a modified form of the cold work peak, presumably due to the dislocation relaxation associated with hydrogen atmosphere. The 230 K sub-peak was observed only after post-straining of the hydrogen-charged specimen and may be attributed to trapped hydrogen bound tightly to lattice defects.

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Two kinds of martensites (stress-induced and thermally-formed) in thin foils of an Fe–328 mass%Ni alloy (M_s∼170 K) have been investigated by means of electron microscopy and diffraction. The stress-induced martensite is observed in as-electropolished thin foils at room temperature, and only in the neighborhood of cracks or edges of the thin foils. Sometimes, the stress-induced martensite is accompanied by fcc twins, which appear as if they were martensite nuclei. The thermally-formed martensite is observed in thin foils cooled below M_s, and in the inner part of the thin foils. Both the martensites exhibit irregular interfaces and internal {112}_M twins, but the distribution of the twins is different from each other. The stress-induced martensite exhibits the Kurdjumov-Sacks orientation relationship for the austenite matrix, whereas the thermally-formed one does the Nishiyama’s. The thermally-formed martensite exhibits another orientation relationship, (111)_A⁄⁄(101)_M and [\bar1\bar12]_A⁄⁄[14\bar1]_M, which is in a {112}_M twin relation with the Nishiyama’s and is for internal twins of the martensite.

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The effect of material parameters on the plastic instability of a dual-phase steel (VAN-QN) sheet in uniaxial tension tested over the temperature range of 78–700 K was investigated employing gridded specimens. Fracture by cleavage occurred at 78 and 200 K and a ductile-to-brittle type transition was indicated in the vicinity of 200 K . The critical strain for diffuse necking ε_d^∗ (which occurred at all temperatures) and that for local necking ε_l^∗ (which occurred at 200–700 K) were found to be in accord with the following derived relationships:
ε_d^∗=n_d+1⁄(δlnε⁄δlnA₀)
ε_l^∗≅2[n_u+m_u(α_l^∗+ε_u)]
where the term δ ln ε⁄δ ln A₀ represents the difference in strain ε at a geometric defect with an initial difference in cross-sectional area A₀. n=d ln σ⁄d ln ε, m=∂ ln σ⁄∂ ln \dotε and α=d ln \dotε⁄d ln ε of the element under consideration, the subscripts indicating the strain at which the measurements were made. The results for the dual-phase steel are compared with those for rimmed steel and the reasons for the better formability of the dual-phase steel at a constant tensile strength are discussed. Dislocation mechanisms operative over the test temperature range are considered.

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Emf measurements of the following galvanic cells with the solid oxide electrolytes (ZrO₂+Y₂O₃ or ZrO₂+CaO) were carried out to determine the standard molar Gibbs energies of formation of ZnO (wurtz) and ZnGa₂O₄ (spinel):
(−)W,Re⁄Zn,ZnO⁄ZrO₂+Y₂O₃⁄In,In₂O₃⁄Re,W(+)
(−)Pt,Re⁄Zn,ZnO⁄ZrO₂+Y₂O₃⁄air,Pt(+)
(−)Pt,Re⁄Cu–10 at%Zn,Ga₂O₃,ZnGa₂O₄⁄ZrO₂+CaO⁄Fe,Fe_xO⁄Pt(+)
(−)Pt,Re⁄Cu–10 at%Zn,ZnO⁄ZrO₂+CaO⁄Fe,Fe₂O⁄Pt(+)
The results were represented by the following equations:
ΔG_f^°⁄J±280=−354560+107.8T⁄K, (843–1067 K)
for Zn(1)+1⁄2O₂(g)→ZnO(wurtz)
and ΔG_f^°⁄J±370=−8640+0.463T⁄K, (988–1172 K)
for ZnO (wurtz)+Ga₂O₃(β)→ZnGa₂O₄ (spinel).

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Modified coulometric titrations on the electrochemical cell: O in liquid Cu–Bi alloys/ZrO₂(+CaO)/Air, Pt, were performed to determine the activity coefficientsof oxygen, γ_O, in liquid Cu–Bi alloys at 1373 K as a function of alloy composition.
A deep upwardly concave curve of the lnγ_O values vs composition was observed over the whole composition range of alloys, as predicted by several solution models. The measured data itself, how-ever, are considerably lower than the calculated values, especially those according to the regular solution model. The interaction parameter of bismuth on oxygen is evaluated from the data for the dilute alloy of bismuth to be −12.0 at 1373 K.

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The relative partial molar quantities of Na₂O in the ternary system were evaluated from an electro-motive force measurement. B₂O₃ functions as an acid more strongly than SiO₂ in the composition studied. Large entropy change of Na₂O implies the nature characteristic of network formation. The results were discussed in comparison with Na₂O–B₂O₃–Al₂O₃ melt.

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