scholarly journals COLD PLASTIC DEFORMATION OF PROCESSES IN CONDITIONS OF BORDER FORMATION

Author(s):  
Vasyl Muzychuk

The article considers the process of forming the inner slot profile on a pipe billet by the method of cold plastic deformation, by compressing them with a matrix on a profile slotted mandrel (by the method of "covering" drawing). A comprehensive study of the mechanics of shaping products to assess their quality and study the possibility of improving the process itself. In the case of three-dimensional molding, the surface of plasticity depends on the history of deformation, which is determined by the change in the stress state with increasing accumulated intensity of deformation. The surface of plasticity in this case is not fixed and can be constructed using the criterion of deformability, which provides the position of the point of the fracture surface, taking into account the history of deformation. The planes of deformation and boundary surfaces of plasticity are constructed, which showed a sufficient margin of plasticity for the process of forming the inner splined profile. It is substantiated that when constructing the load trajectory in the space of dimensionless indicators and its type is unambiguously determined by the conditions of formation characteristic of the studied process and practically does not depend on the mechanical properties of the deformed metal. The areas of deformation closest to the failure are determined by indicators that take into account the influence of the first and third invariants of the stress tensor (lateral region and area of depressions of the profile relative to the process of forming the internal splined profile), in which the used plasticity reaches values = 0,34 ... 0,4. From the point of view of providing a margin of safety, such calculations must be performed taking into account the indicator that takes into account the influence of the third invariant of the stress tensor.

2011 ◽  
Vol 56 (2) ◽  
pp. 503-508 ◽  
Author(s):  
R. Pęcherski ◽  
P. Szeptyński ◽  
M. Nowak

An Extension of Burzyński Hypothesis of Material Effort Accounting for the Third Invariant of Stress Tensor The aim of the paper is to propose an extension of the Burzyński hypothesis of material effort to account for the influence of the third invariant of stress tensor deviator. In the proposed formulation the contribution of the density of elastic energy of distortion in material effort is controlled by Lode angle. The resulted yield condition is analyzed and possible applications and comparison with the results known in the literature are discussed.


2014 ◽  
Vol 2 (3) ◽  
Author(s):  
Redacción CEIICH

<p class="p1">The third number of <span class="s1"><strong>INTER</strong></span><span class="s2"><strong>disciplina </strong></span>underscores this generic reference of <em>Bodies </em>as an approach to a key issue in the understanding of social reality from a humanistic perspective, and to understand, from the social point of view, the contributions of the research in philosophy of the body, cultural history of the anatomy, as well as the approximations queer, feminist theories and the psychoanalytical, and literary studies.</p>


PEDIATRICS ◽  
1957 ◽  
Vol 20 (3) ◽  
pp. 552-556
Author(s):  
Reginald S. Lourie

FROM the viewpoint of the pediatric psychiatrist, the problems of obesity, as seen clinically, can be thought of as having three layers. The first is constitutional, better described as physiologic, which may be broken down into genetic and structural elements. The second is psychologic, consisting of the values that food intake or the obesity itself come to have. The third layer is made of the cultural and social reactions to food and fat. These attitudes encountered inside and outside the home intermesh in their effects with the physiologic and psychologic levels. These, in turn, are also interwoven, until one cannot separate one layer from the other. However, when individual cases are scrutinized they reveal the pathology at one layer or the other to predominate and indicate where efforts to modify the abnormality might best be directed. Incidentally, the same levels operate on the other side of the coin, anorexia. From the practical point of view, let us consider the natural history of obesity and the clinical varieties one sees in practice, and let us see how the three-layer concept fits. First, as pointed out by Gordon, there is a tendency to be complacent or even pleased with obese infants. At level one, the physiologic, such constitutional factors as those present in the neonate born with an excessive quantity of pepsinogen secreted by the gastric mucous membrane could have the effect of producing as Mirsky points out, a relatively intense or even continuous hunger, and make greater demands on its mother for nursing.


Traditio ◽  
1968 ◽  
Vol 24 ◽  
pp. 247-292 ◽  
Author(s):  
Alfred A. Triolo

What was Dante's interpretation of the third Aristotelian disposition of Nicomachean Ethics 7, which he calls ‘la matta bestialitade’ and how does it function in the structure of the Inferno? Correlatively, what range of meaning did Dante assign the second disposition, ‘malizia’? The problem is difficult at best and, from a modern point of view, apparently literarily unrewarding. What is more, after a long tradition of scholarly discussion and dispute a kind of consensus has emerged. With the solution which it proposes most are willing to rest content and indeed many simply take its correctness for granted. It is the thesis of this study that the consensus is based on an improvisation and that the high probability of an alternative solution can be effectively demonstrated. Underlying this is the conviction that this is not a scholarly quibble, of interest only to the ‘experts’ or merely a matter of interest for the history of ideas. Rather it is a problem with profound significance for the total structure of the Inferno both intellectual and literary.


2011 ◽  
Vol 243-249 ◽  
pp. 2183-2187
Author(s):  
Jun Xin Liu ◽  
Zhong Fu Chen ◽  
Wei Fang Xu

For soils, failure occurs with lower deviatoric stress under the same pressure (the first invariant of stress tensor) in TXE compared with the strength of the triaxial compression, which is indicated that the strength of soils strongly depends on the third invariant of stress deviator; Although in the traditional Mohr-Coulomb criterion it can be reflected in difference of strength between triaxial extension and compression under the same pressure, it’s nothing to do with the pressure for the strength ratio between triaxial extension and compression. By TXC and TXE, changes of deviatoric stress and the ratio with the pressure were studied


2012 ◽  
Vol 38 (4-5) ◽  
pp. 477-483 ◽  
Author(s):  
Akeel Bilgrami

This short essay analyzes the deception and self-deception in talk of ‘the clash of civilizations’ and proceeds to diagnose what is wrong in the standard understanding of Islam in the Western media today by looking to the abiding history of colonial relations with Islam down to this day and also looking to the relation between ideals of democracy and the formation of religious identities. The essay closes with some remarks about the nature of identity and the importance to one's own agency of the distinction between the first and the third person point of view in Muslim self-understanding.


1974 ◽  
Vol 96 (3) ◽  
pp. 207-213 ◽  
Author(s):  
S. Murakami ◽  
Y. Yamada

Creep theories with the effect of the third invariant of the deviatoric stress tensor and their accuracy as applied to practical problems are discussed. Constitutive equations for transient creep are first formulated by assuming creep potentials of the Prager-Drucker and the Bailey-Davis type together with the associated equivalent stress functions. Strain-hardening and time-hardening hypotheses are assumed. Experimental results hitherto reported for thin-walled tubes are discussed according to these equations. Then, the creep of a thick-walled tube of mild steel is analyzed and compared with experiments.


Author(s):  
Daniele Castrizio

The paper examines the coins found inside the Antikythera wreck. The wreck of Antikythera was discovered by chance by some sponge fishermen in October 1900, in the northern part of the island of Antikythera. The archaeological excavation of the wreck has allowed the recovery of many finds in marble and bronze, with acquisitions of human skeletons related to the crew of the sunken ship, in addition to the famous “Antikythera mechanism”. Various proposals have been made for the chronology of the shipwreck, as well as the port of departure of the ship, which have been based on literary sources or on the chronology of ceramic finds. As far as coins are concerned, it should be remembered that thirty-six silver coins and some forty bronze coins were recovered in 1976, all corroded and covered by encrustations. The separate study of the two classes of materials, those Aegean and those Sicilian allows to deepen the history of the ship shipwrecked to Antikythera. The treasury of silver coinage is composed of thirty-six silver cistophoric tetradrachms, 32 of which are attributable to the mint of Pergamon and 4 to that of Ephesus. From the chronological point of view, the coins minted in Pergamon have been attributed by scholars to the years from 104/98 B.C. to 76/67 B.C., the date that marks the end of the coinage until 59 B.C. The coins of Ephesus are easier to date because they report the year of issue, even if, in the specimens found, the only legible refers to the year 53, corresponding to our 77/76 B.C., if it is assumed as the beginning of the era of Ephesus its elevation to the capital of the province of Asia in 129 B.C., or 82/81 B.C., if we consider 134/133 B.C., the year of the creation of the Provincia Asiana. As for the three legible bronzes, we note that there are a specimen of Cnidus and two of Ephesus. The coin of the city of Caria was dated by scholars in the second half of the third century B.C. The two bronzes of Ephesus are dated almost unanimously around the middle of the first century B.C., although this fundamental data was never considered for the dating of the shipwreck. The remaining three legible bronzes from Asian mints, two from the Katane mint and one from the Panormos mint, belong to a completely different geographical context, such as Sicily, with its own circulation of coins. The two coins of Katane show a typology with a right-facing head of Dionysus with ivy crown, while on the reverse we find the figures of the Pii Fratres of Katane, Amphinomos and Anapias, with their parents on their shoulders. The specimen of Panormos has on the front the graduated head of Zeus turned to the left, and on the verse the standing figure of a warrior with whole panoply, in the act of offering a libation, with on the left the monogram of the name of the mint. As regards the series of Katane, usually dated to the second century B.C., it should be noted, as, moreover, had already noticed Michael Crawford, that there is an extraordinary similarity between the reverse of these bronzes and that of the issuance of silver denarii in the name of Sextus Pompey, that have on the front the head of the general, facing right, and towards the two brothers from Katane on the sides of a figure of Neptune with an aplustre in his right hand, and the foot resting on the bow of the ship, dated around 40 B.C., during the course of the Bellum siculum. We wonder how it is possible to justify the presence in a wreck of the half of the first century B.C. of two specimens of a very rare series of one hundred and fifty years before, but well known to the engravers of the coins of Sextus Pompey. The only possible answer is that Katane coins have been minted more recently than scholars have established. For the coin series of Panormos, then, it must be kept in mind that there are three different variants of the same type of reverse, for which it is not possible to indicate a relative chronology. In one coin issue, the legend of the ethnic is written in Greek characters all around the warrior; in another coin we have a monogram that can be easily dissolved as an abbreviation of the name of the city of Panormos; in the third, in addition to the same monogram, we find the legend CATO, written in Latin characters. In our opinion, this legend must necessarily refer to the presence in Sicily of Marcus Porcius Cato of Utica, with the charge of propraetor in the year 49 B.C. Drawing the necessary consequences from the in-depth analysis, the data of the Sicilian coins seem to attest to their production towards the middle of the first century B.C., in line with what is obtained from the ceramic material found inside the shipwrecked ship, and from the dating of the coins of Ephesus. The study of numismatic materials and a proposal of more precise dating allows to offer a new chronological data for the sinking of the ship. The presence of rare bronze coins of Sicilian mints suggests that the ship came from a port on the island, most likely from that of Katane.


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