C.P. Cutler

Bio: C.P. Cutler is an academic researcher from University of Cambridge. The author has contributed to research in topics: Superplasticity & Eutectic system. The author has an hindex of 3, co-authored 3 publications receiving 83 citations.

Creep behaviour in the superplastic Pb–62% Sn eutectic

Abstract: The creep behaviour of the superplastic Pb-62% Sn eutectic was investigated for grain sizes from 5·8 to 14·5 μm and at temperatures in the range from 336 to 422 K. The results showed a sigmoidal relationship between strain rate and stress. At intermediate strain rates (∼ 10−5–10−2 sec−1), the stress exponent was ∼1·65, the exponent of the inverse grain size was ∼2·3, and the activation energy was similar to the value anticipated for grain boundary diffusion. At very low strain rates (≲10−5 sec−1), the stress exponent was ∼3·0, the exponent of the inverse grain size was ∼2·3, and the activation energy was similar to the value anticipated for lattice self-diffusion. The results are not entirely consistent with either of the two major theories of superplasticity, but suggest instead the sequential operation of two different deformation processes.

Microstructural aspects of superplasticity

Abstract: The microstructural aspects of the superplastic phenomenon are reviewed. The experimental results of a very large number of investigations are critically analysed in the context of: grain shape and size; grain growth; grain boundary sliding and migration, grain rotation and rearrangement; diffusion and dislocation activity. It is shown, that in spite of often conflicting evidence in the literature, a common pattern of microstructural behaviour emerges for all the materials and conditions investigated to date.

Relative motion of grains during superplastic flow in an Al-9Zn-1 wt.%Mg alloy

Abstract: The topological feature of the relative motion of grains during superplastic flow of an Al-9.3Zn-1.03Mg-0.22 wt.%Zr alloy has been examined by the translation of reference markers in the surface and interior of specimens. Microstructural evidence was obtained for grain-switching events based on the relative motion of a group of four grains. The translation of the grains seemed to occur by sliding and rotation. On the basis of the results of a texture study, accommodation strains required in this process are attributed predominantly to slip. Hence, the role played by slip in deformation at maximum strain-rate sensitivity is particularly significant for this alloy.