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Einkristallines und polykristallines Eisen-II-Oxid, Fei1–xO, mit einem Kationenleerstellengehalt von 0, 05 ≦ x ≦ 0, 11 wurde im Stauchversuch bei Temperaturen 650 °C ≦ T ≦ 1300 °C statisch und dynamisch verformt. Stationares Kriechen und dynamisches Fliesen lassen sich beschreiben durch die Zustandsgleichung e˙ = C (1 + bx) σm exp( –U/kT) mit m = 4 und U = (3.54 ± 0,21) eV ⌆ (81, 5 ± 4.8) kcal/mol. Einkristalle sind weicher und duktiler als Polykristalle. Fe1–xO wird mit steigendem Leerstellengehalt x plastischer. Fur die beobachtete Streckgrenze werden die von Fe3O4-Ausscheidungen herruhrenden Versetzungsringe verantwortlich gemacht. Die Ergebnisse lassen sich durch ein von der Spannung unterstutztes Klettern von Stufenversetzungen deuten. An investigation is made of compressive deformation in monocrystalline and polycrystalline ferrous oxide Fe1-xO, with a concentration of cation vacancies 0.05≦x≦0.11, in the temperature range 650 °C ≦ T ≦ 1300 °C. Stationary creep as well as flow at constant strain rate can be expressed as e˙ = C (1 + bx)σm exp (– U/kT) with m = 4 and U = (3.54 ± 0.21) eV ⌆ (81.5 ± 4.8) kcal/mol. Single crystals are found to be softer and ductiler than polycrystalline samples. The plasticity of Fe1–xO increases with increasing concentration of iron vacancies. The observed yield point is thought to be due to dislocation loops, resulting from Fe3O4 precipitates. The results are interpreted in terms of stress-induced climb of edge dislocations.

The compressive deformation behavior of polycrystalline iron-aluminum alloys has been investigated (i) at 298°K for specimens heat treated in various ways and containing from 22.0 to 31.7 at% Al, and (ii) from 77 to 655°K for well-annealed specimens containing 26.6 at% Al. Alloys which possess significant DO3 type long range order exhibit marked composition and temperature dependent variations in deformation behavior. Specifically, those containing ⪆ 27 at% Al exhibit two linear and one parabolic deformation stage at 298°K. The linear stages are shown to be a result of the production and motion of DO3 type superlattice dislocations. The absence of these stages in well-annealed specimens is attributed to the lack of thermal assistance for the DO3 superlattice dislocation nucleation process. The flow stress levels which characterize the two linear stage behavior agree with calculations of the stress required for production of antiphase boundaries. Results obtained from quenched specimens are in agreement with the above conclusions, and the changes induced by quenching are in accord with calculations of the effect of thermal antiphase boundaries upon dislocation motion. Das Verformungsverhalten bei Kompression von polykristallinen Eisen-Aluminium-Legierungen wurde: 1. bei 298°K fur Proben, die in verschiedener Weise getempert waren und zwischen 22,0 und 31,7 At% Al enthielten und 2. zwischen 77 und 655 °K fur ausgetemperte Proben mit 26,6 At% Al untersucht. Legierungen, die eine betrachtliche Fernordnung von DO3-Typ besitzen, zeigen merkliche Anderungen im Deformationsverhalten, die von Zusammensetzung und Temperatur abhangen. Proben mit ⪆ 27 At% Al zeigen spezifisch einen parabolischen und zwei lineare Deformationsstufen bei 298 °K. Es wird gezeigt, das die linearen Stufen ein Ergebnis der Bildung und Wanderung von Versetzungen des DO3-Ubergitters sind. Das Fehlen dieser Stufen in ausgetemperten Proben wird dem Fehlen thermischer Assistenz fur den Bildungsprozes der DO3-Ubergitterversetzungen zugeschrieben. Die niedrigen Flusniveaus, die das Verhalten der beiden linearen Stufen charakterisieren, stimmen mit den Berechungen der Spannungen uberein, die fur die Bildung von Antiphasengrenzen notwendig sind. Die Ergebnisse, die fur die getemperten Proben erhalten werden, befinden sich in Ubereinstimmung mit den oben angefuhrten Schlussen, und die durch Tempern induzierten Anderungen stimmen mit Berechnungen des Einflusses der thermischen Antiphasengrenzen auf die Versetzungswanderung uberein.

An acoustic emission test facility was designed and constructed to allow constant strain rate compressive deformation of samples up to an applied load of approximately 180 kg. Strain rates of from 1.6×10−3 to 3.2×10−6 sec−1 were obtained with total system noise limited to less than 10 μV peak‐to‐peak referred to the input of the pre‐amplifier. Over‐all signal amplification was 9900±100 over a bandwidth of 200 Hz–200 kHz.

One stroke of compressive load, at the same load-speed as that caused by earthquake was given onto the concrete and mortar specimen. The relationship between stress and strain, and failure conditions were looked into, and the findings were compared with ordinary statical compressive tests.As a result, it was found that almost linear relations existed between the dynamical strength of failure and the logarithmic value of failure time (0.03sec.-100sec.); that the shorter the failure time, the larger the strength of failure; and that compressibility in the strength of failure was almost unchanged regardless of failure time. It was also noticed that the smaller the failure time was, the steeper the stress-strain curve became, a relationship which substantiates a high degree of viscosity.The authors have attempted to explain the dynamical behaviors of concrete and mortar approximatively by obtaining the coefficient of elasticity and coefficient of viscosity of the simple 3-element model which is composed of the Kelvin body and a spring connected directly to it.

The permanent compress! ve deformation of pyrolytic graphite rapidly heated to very high temperatures and loaded in the c direction has been determined experimentally. The test samples were heated resistively while loaded with a calibrated cluster of helical springs. Temperature ranged from 2200° to 3000 °C, times ranged from 10 to 50 sec, and stress ranged from 4200 to 30,000 psi. The data show that the presence of loading lowers the threshold temperature of permanent deformation and significantly increases the deformation rate. Deformation at no load was found to occur at 2600°C; however, permanent deformation was observed at low loads (4200 psi) at temperatures slightly above the deposition temperature. Deformation is very rapid at temperatures above 2600 °C when load is applied. Catastrophic failure of the pyrolytic graphite occurred 5 sec after a sample was heated to 3000 °C when loaded to 13,000 psi. Reheating and reloading of the material appear merely to extend the initial deformation curve. Structural transformation, as evidenced by a decrease in the unit cell dimension CQ, occurred in samples that were tested at the higher temperatures.

The self-diffusion coefficient of silver undergoing plastic compressive deformation was measured over temperatures ranging from 810 to 1172°K and at strain rates from 0.00075 to 0.006 hr −1 . At all temperatures it was found that the diffusion coefficient is proportional to the strain rate. The results were interpreted on the basis of a model in which two vacancy-production mechanisms and two vacancy-annealing mechanisms are assumed to be operative. At low temperatures, vacancy production is assumed to occur by a geometric, temperature-independent process, and the annealing mechanism is assumed to be the migration of vacancies to fixed sinks. At high temperatures, it is suggested that vacancies are formed by a thermally activated process and that they anneal by combining with a highly mobile defect. Energetic considerations lead to the conclusion that this mobile defect is probably a divacancy.

目的 すでに報告したカーペットの圧縮変形理論をさらに改良し, パイルに双糸を用いたカットパイルカーペットにも適用し得るよう拡張した. 成果 (1) パイル糸の圧縮特性を導入できるようにカーペットの圧縮変形モデルの改良を行ない理論式を誘導した. (2) パイルに双糸を用いたカットパイルカーペットに改良理論式を適用した結果, よい精度のあることが確認できた.

It is supposed that there is a close relation between the compressive property of fabric and sensory hardness which can be detected by hand metric method. At first, the compressive property, which has non-linear behavior such as non-linear property in the compressive deformation and hysteresis behavior in the recovery property, is characterized and represented by some number of characteristic constants. And then, forty one samples of woven fabric used for men's suits are measured to obtain those characteristic constants. On the other hand, these samples are tested by an expert of hand ling testing to number them in order of sensory hardness, and the order is transformed to numbers between 0 to 10 following to the order.At first, the linear regression between W (energy required for compressing fabric up to pressure of 50 g/cm2) and Y (= sensory value of hardness) and Y [1] are caluculated using W values by the regression. The residual error, Y-Y [1] , is also related with the next characteristic value, for example β, and checked the relation between Y and β and so on, where, β is the value which represents the characteristics of non-linear curve of pressure-thickness relation.The conclusion shows that all characteristic values which are not so correlated with W have some amounts of relation with Y. The contributions of these values to Y value are examined.

The effect of composition on the properties (bulk resistivity, hardness, compressive deformation, density, and microstructure) of polypropylene-aluminum specimens has been investigated. The changes are not additively related with the composition. An explanation of the observations is proposed.

To enable the compressive deformation properties of some kinds of carpets to be calculated, their compressive mechanism has been analyzed.With the aid of some hypotheses presented, the theoretical equations have been derived on the basis of the thin rod theory on elastica.The experimental curves on flocked or tufted carpet have been compared with the theoretical ones with fairly good agreement, thus verifying that the above hypotheses and theoretical equations are almost right.

A technique is described for determining coefficients of friction in a simple forging operation involving the deformation of a flat ring-shaped specimen between flat dies. This technique involves only the measurement of the change in shape of the ring upon compression and does not require a knowledge of the mechanical properties of the metal under the conditions of testing. It is therefore applicable over a wide range of testing conditions with respect to temperature, amount and rate of deformation, lubrication, etc. This technique has been used to study the limiting conditions of several lubricants for hot and cold working. The possible application of frictional data obtained by this technique to mechanical working operations is discussed.

Samples of 65 μm-grain-size AL2O3 containing 0.05 wt% Mg and 40 μm-grain-size AL2O3 containing 0.13 wt% Mg, both MgO-saturated, undergo compressive deformation in the range 1580° to 1800°C with results interpreted as diffusional creep rate-limited by grain-boundary diffusion with the Coble boundary-diffusion model giving A lower deformation rate for an unsaturated composition indicates that MgO additions enhance grain-boundary diffusion.

Compressive deformation studies on BaTiO3 single crystals show that the crystals deform easily at room temperature because of the movement of twin boundaries which are the 90° domain walls. In the twin‐deformation region, the crystals exhibit time‐dependent deformation, which could be observed as stress relaxation. Some features of this deformation and relaxation behavior are reported.

Recrystallization of KCl crystals deformed in a direction was utilized to develop polycrystalline microstructures, increasing yield stresses, thus making them more attractive as laser window candidates. Using press forging techniques (i.e., slow compressive deformation in the absence of lateral constraints), large plastic strains (≤ 70%) were achieved at temperatures as low as 150 °C, which resulted in recrystallized grain sizes as fine as 5 μm. Although a residual texture was present, there was sufficient grain misorientation to result in general polycrystalline behavior. The yield stresses of the press forged materials increased with decreasing grain size, reaching about 35 MN m−2 (∼5000 psi) at the finest (5 μm) grain size.