The cyclic work-hardening of a bainitic steel was studied by rotation-bending and tension-compression tests. It was found that it is possible to determine the endurance limit against fatigue for this material by means of cyclic work-hardening once the critical value of the ratio \hatσ⁄τ, applied stress amplitude over instantaneous flow strength, has been determined. Work-hardening parameters p and h (flow parameter and hardening parameter, respectively) can be used to check the obtained critical value of \hatσ⁄τ in order to achieve reliable results.

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The influence of the concurrent phase transformation on the deformation of ferritic and pearlitic ductile cast irons was studied under tensile stresses at high and low thermal cycling rates. Transformation plasticity, characterized by the linear relationship between the transformation strain per cycle and the externally applied stress (i.e., strain rate sensitivity exponent, m is 0.8), was observed under all conditions. The transformation strain is greater on heating from pearlite to austenite than on cooling from austenite to pearlite. The transformation strain at the high heating and cooling rate results in a smaller transformation strain. Large uniform elongations (above 200%) can be obtained by repeated thermal cycling under a constant stress. It is suggested that the plasticity is due to the creep enhanced by excess vacancies generated during the volume change. In the early thermal cycling, the voids are formed at both sides of the spheroidal graphite. In the later stage, the voids are filled up with the matrix structure successively.

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In order to investigate the origin of the recrystallized grains with preferred orientation in low carbon steel sheets, the regions of twisted crystal lattice resulting from the dislocation slip being blocked during cold-rolling were examined. The rotation rates for various orientations were mathematically deduced. The cold-rolling deformation was assumed to progress under the plane-strain condition and by operation of the ⟨111⟩ pencil glide systems. The {554}⟨225⟩ preferred orientations in the recrystallization texture of the niobium-added steel rotate about the ⟨110⟩ axes inclined ±60° from the rolling direction toward {211}⟨011⟩ with increasing cold reduction. The rotation rate of the preferred orientation in the recrystallization texture was found to coincide with that of the twisted region calculated from the theory. It is concluded that the {554}⟨225⟩ type recrystallization texture in the niobium-added steel develops from the regions of heavily twisted lattice.

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This report is concerned with fundamental research into the properties of deep drawing of Al–Mg system alloy sheets with respect to the following points:
(i) Influence of additive Mg amounts on properties of deep drawing; (ii) influence of third additive elements on properties of deep drawing; (iii) X-ray texture; and (iv) the relation of the ear after deep drawing to “n” and “r” values.
The following conclusions were drawn from the foregoing experiments:
(1) An increase in additive Mg content augments the limiting drawing ratio and the appropriate drawing area expanded. Of the seven alloy sheets, Al-6.08%Mg alloy showed a favorable value.
(2) “r” and “n” values were quite compatible with deep drawing properties.
With increase in Mg content, the values showed a tendency to increase and become nearly content at 5–6%Mg.
(3) Minute additions of Mn, Cr, Zr and Ti as third elements tended to reduce the deep drawing properties. However, Al-5.85%Mg-0.14%Mn alloy sheets did not reduce the deep drawing properties but increase the strength.
(4) The ear emergency direction and earing ratio were fairly compatible with the “r” value. With an increase in the addition of the third elements, the earing ratio appeared to be reduced.
(5) As to the recrystallization texture, (001)[\bar110] appeared strongly and all ears emerged in a 45° direction.

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The applicability of the dip test to the measurement of the mean internal stress during deformation was examined. It is found that the method is valid only when the dislocation velocity is proportional to the effective stress or when the internal stress is nearly 100% of the flow stress. An extrapolation method is proposed to minimize the error of the dip test. By applying this method to the high-temperature deformation of high-purity aluminium and Al-5.7 at%Mg and from above theoretical prediction, it is found that the internal stress is the main component of the flow stress in pure aluminium, while the frictional stress contribution is as large as that of the internal stress in the Al–Mg alloy.

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Measurements of Young’s modulus at −150∼400°C and of thermal expansion, rigidity modulus and hardness at room temperature were made for Mn–Cu–V alloys subjected to various heat treatments and cold working. The results showed that anomalous changes associated with antiferromagnetic\ ightleftarrowsparamagnetic transformations occur in the Young’s modulus vs temperature curves of the ternary alloys in the annealed state. The temperature coefficient of Young’s modulus, e, varies markedly by annealing, cold working and water quenching, and also shows a large dependence on composition. In the e vs composition curve of the alloys a large positive maximum of e appears, indicating the presence of the Elinvar characteristics.

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