Pillars of Flame by Night The Dance Motif in D. H. Lawrence's Poetry

Langdon Elsbree 한국로렌스학회 2007 D.H. 로렌스 연구 Vol.15 No.3

This essay, Part of a larger work-in-progress, explores the dance in Hardy's and Lawrence's poetry My approach to Lawrence's poems is mediated by two perspectives The first is Lawrence's distinction between poetry of the past ("a dance where the hands link. . .for the supreme moment at the end") and poetry of the "immediate present" ("motion. . . haste. . .immediacy. . .without denouement") Much of Hardy's poetry, I will simply assert here, is poetry of the past, including the ones where the dance figures Lawrence's poetry, by contrast, is emphatically of the immediate present, certainly so in the ones touching the dance The second perspective is that of Amit Chaudhuri's D. H. Lawrence and Difference Chaudhuri emphasizes how "the frame" around each poem is constantly broken down by repetition so that images and motifs of one poem may occur in another This resulting fluidity and intertexuality precludes the "masterpiece," separate and perfected, and is an aesthetic like Ruskin's valuing of the Gothic for its heterogeneity and imperfection rather than hierarchy and regularity This perspective foregrounds the significant motif of the dance which has multiple meanings often narrowing the distance between poems but not evolving into a single pattern This perspective also facilitates isolating selected passages from poems both to suggest how energized or unexpected their meanings are, without claiming the poem as a whole is a consistently sustained "masterpiece " Examples follow Concerning Lawrence's work, the polarities of light and darkness occur in his dance images in both earlier and later poems Though the shadow and night become increasingly dominant, darkness has no single meaning, but rather a cluster of meanings the need for / presence of creativity freedom and excess in exploration of the unknown the source of milieu of male sexuality and vigor the complement of light's purity In the courtship poems of Look! We Have Come Through! the dance signifies both the vindication of and tension between the lovers as they struggle to become a couple In later poems the dance's meaning alternates between the poles of masculine physicality, and jazz as the mechanical, mechanized convulsions of the industrial system's prisoners Above all, the dance's most vivid scenes show us "Pillars of Flame by Night"

필연성의 예언자들

랭던 위너(Langdon Winner),장영배(번역자) 과학기술정책연구원 1998 과학기술정책 Vol.- No.112

Review: achieving superplastic properties in ultrafine-grained materials at high temperatures

Kawasaki, Megumi,Langdon, Terence G. Springer-Verlag 2016 JOURNAL OF MATERIALS SCIENCE - Vol.51 No.1

<P>The mechanisms of superplasticity occurring in conventional materials, having grains sizes of the order of a few microns, are now understood reasonably well. However, very recent advances in the processing of ultrafine-grained (UFG) metals have provided an opportunity to extend the understanding of flow behavior to include UFG materials with submicrometer grain sizes. In practice, processing through the application of severe plastic deformation (SPD), as in equal-channel angular pressing (ECAP) and high-pressure torsion (HPT), has permitted the fabrication of relatively large samples having UFG microstructures. Since the occurrence of superplastic flow generally requires a grain size smaller than similar to 10 mu m, it is reasonable to anticipate that materials processed by SPD will exhibit superplastic ductilities when pulled in tension at elevated temperatures. This review examines recent results that demonstrate the occurrence of exceptional superplastic flow in a series of UFG aluminum and magnesium alloys after ECAP and HPT. The results are analyzed to evaluate the superplastic flow mechanism and to compare with materials processed using different techniques. The critical issue of microstructural inhomogeneity is examined in two-phase UFG materials after SPD processing and the influence of microstructural homogeneity on the superplastic properties is also demonstrated.</P>

Description of the Superplastic Flow Process by Deformation Mechanism Maps in Ultrafine-Grained Materials

Kawasaki, Megumi,Langdon, Terence G. Trans Tech Publications, Ltd. 2016 Materials science forum Vol.838 No.-

<P>The synthesis of ultrafine-grained (UFG) materials is very attractive because small grains lead to excellent creep properties including superplastic ductility at elevated temperatures. Severe plastic deformation (SPD) is an attractive processing technique for refining microstructures of metallic materials to have ultrafine grain sizes within the submicrometer to even the nanometer level. Among the SPD techniques, most effective processing is conducted through equal-channel angular pressing (ECAP) and high-pressure torsion (HPT) and there are numerous reports demonstrating the improved tensile properties at elevated temperature. This report demonstrates recent results on superplasticity in metals after ECAP and HPT. Moreover, superplastic flow of the UFG materials is evaluated by using flow mechanisms developed earlier for coarse-grained materials and depicted by plotting deformation mechanism maps which provide excellent visual representations of flow properties over a wide range of testing conditions.</P>

Factors Influencing Microstructural Development in Equal-Channel Angular Pressing

Furukawa, Minoru,Horita, Zenji,Langdon, Terence G. 대한금속재료학회 2003 METALS AND MATERIALS International Vol.9 No.2

Processing through the imposition of severe plastic deformation (SPD) provides an opportunity for achieving very significant grain refinement in bulk materials. Although different SPD procedures are available, the process of equal-channel angular pressing (ECAP) is especially attractive because it can be scaled easily to produce relatively large samples. This paper describes the principles of ECAP processing and demonstrates the potential for achieving unusual mechanical properties in the samples subjected to ECAP. Special emphasis is placed on the possibility of attaining a high strain rate superplastic forming capability in the as-pressed materials: examples are presented for an Al-Mg-Sc alloy prepared in the laboratory by casting and for a commercial Al-2024 alloy.

Review: Overcoming the paradox of strength and ductility in ultrafine-grained materials at low temperatures

Kumar, Praveen,Kawasaki, Megumi,Langdon, Terence G. Springer-Verlag 2016 JOURNAL OF MATERIALS SCIENCE - Vol.51 No.1

<P>Ultrafine-grained (UFG) materials with grain sizes in the submicrometer or nanometer range may be prepared through the application of severe plastic deformation (SPD) to bulk coarse-grained solids. These materials generally exhibit high strength but only very limited ductility in low-temperature testing, thereby giving rise to the so-called paradox of strength and ductility. This paradox is examined and a new quantitative diagram is presented which permits the easy insertion of experimental data. It is shown that relatively simple procedures are available for achieving both high strength and high ductility in UFG materials including processing the material to a very high strain and/or applying a very short-term anneal immediately after the SPD processing. Significant evidence is now available demonstrating the occurrence of grain boundary sliding in these materials at low temperatures, where this is attributed to the presence of non-equilibrium grain boundaries and the occurrence of enhanced diffusion along these boundaries.</P>

Microstructural homogeneity and superplastic behavior in an aluminum-copper eutectic alloy processed by high-pressure torsion

Kawasaki, Megumi,Lee, Han-Joo,Langdon, Terence G. Springer-Verlag 2015 JOURNAL OF MATERIALS SCIENCE - Vol.50 No.20

Superplastic Flow and Micro-Mechanical Response of Ultrafine-Grained Materials

Kawasaki, Megumi,Jang, Jae Il,Langdon, Terence G. Trans Tech Publications, Ltd. 2018 Diffusion and defect data. DDF. Pt. A, Defect and Vol.385 No.-

<P>The bulk ultrafine-grained (UFG) materials usually show superior mechanical properties. Since the occurrence of superplastic flow generally requires a grain size smaller than ~10 μm, it is anticipated that materials processed by severe plastic deformation (SPD) will exhibit superplastic ductilities when pulled in tension at elevated temperatures. Recent advances in the processing of UFG metals have provided an opportunity to extend the understanding of superplastic flow behavior to include UFG materials with submicrometer grain sizes. Recent studies showed the UFG materials demonstrated the development of plasticity in micro-mechanical response at room temperature by the significant changes in microstructure attributed to high-pressure torsion (HPT). Accordingly, this study summarizes recent results on excellent ductility and plasticity in a UFG Zn-22% Al alloy. Specifically, the alloy demonstrated the occurrence of exceptional superplastic flow at high temperature after equal-channel angular pressing and HPT and excellent room temperature plasticity of the alloy after HPT where the plasticity was evaluated by the nanoindentation technique. The significance of purity of the alloy is also considered for enhancing the ductility at room temperature.</P>

Equal - Channel Angular Pressing : A Novel Tool for Microstructural Control

NEMOTO, Minoru,Horita, Zenji,Furukawa, Minoru,Langdon, Terence G . 대한금속재료학회(대한금속학회) 1998 METALS AND MATERIALS International Vol.4 No.6

The principles of equal-channel angular (ECA) pressing are reviewed. It is demonstrated that this processing procedure is capable of introducing an ultrafine grain size into bulk materials and the precise nature of the microstructure is dependent upon the total strain introduced by the pressing. When the strain is sufficiently high, it is possible to achieve very high tensile ductilities at high strain rates, thereby providing the potential for substantially increasing the viability of superplastic forming in the metal forming industry.

Microstructural evolution and mechanical properties in a Zn-Al eutectoid alloy processed by high-pressure torsion

Cho, T.S.,Lee, H.J.,Ahn, B.,Kawasaki, M.,Langdon, T.G. Elsevier Science 2014 Acta materialia Vol.72 No.-

Experiments were conducted to examine the evolution of microstructure and mechanical properties in a Zn-22% Al eutectoid alloy processed by high-pressure torsion (HPT). Measurements of the Vickers microhardness revealed significant weakening in the alloy after HPT, and microstructural analysis showed that the initial duplex structure, consisting of equiaxed grains and lamellae, was retained at the disk centers after HPT, whereas equiaxed fine grains were observed at the disk edges. Direct evidence is presented for a transformation of the lamellae into equiaxed very fine grains and subsequent dynamic recrystallization in the early stages of HPT. The reduction of the lamellar structure and the loss of Zn precipitates account for the weakening in the alloy in HPT processing. Excellent high strain rate superplasticity was recorded after HPT, with elongations up to ~1800% at 473K at a strain rate of 10<SUP>-1</SUP>s<SUP>-1</SUP>. The experiments show that the maximum elongations are displaced to faster strain rates with increasing numbers of HPT turns.