An Index to LATR 31/1 (Fall 1997) to 35/2 (Spring 2001)

An Index to LATR 31/1 (Fall 1997) to 35/2 (Spring 2001

An Index to LATR 26/1 (Fall 1992) to 30/2 (Spring 1997)

An Index to LATR 26/1 (Fall 1992) to 30/2 (Spring 1997

An Index to LATR 21/1 (Fall 1987) to 25/2 (Spring 1992)

An Index to LATR 21/1 (Fall 1987) to 25/2 (Spring 1992

Evolution of Austenite Microstructure and Precipitation State during Hot Rolling of a Nb-Microalloyed Steel

Hot torsion tests were used to simulate hot rolling of a Nb-microalloyed steel. Subsequent graphic representation of Mean Flow Stress (MFS) versus the inverse of absolute temperature for each pass allowed to know the critical rolling temperatures (Tnr Ar3, Ar1,)) and residual stress accumulated in austenite just before austenite to ferrite phase transformation. It has been found that, as successive rolling passes are applied at temperatures below Tnr, mean precipitate size decreases as a result of deformation applied and hardening by incomplete recrystallization of austenite.Peer reviewe

Influence mutual of the deformation and chemical composition on induced precipitation in microalloyed steels

[ES] Mediante ensayos de torsión y usando el método hack extrapolation se ha determinado la cinética de recristalización estática de aceros microaleados con vanadio (V), niobio (Nb) y titanio (Ti) y, a partir de las mismas, ha sido posible dibujar los diagramas recristalizaciónprecipitación- tiempo'temperatura (RPTT), que muestran gráficamente la interacción recristalización-precipitación. Estos diagramas muestran que el efecto de la deformación en la cinética de precipitación depende del contenido de microaleante. En este sentido, se propone una nueva expresión para relacionar la influencia de la deformación y del contenido de microaleante sobre el periodo mínimo de incubación de la precipitación inducida.[EN] By means of torsion tests and applying the "back extrapolation" method, the static recrystallization kinetics in microalloyed steels with vanadium (V), niobium (Nb) and titanium (Ti) has been determined and, recrystallization-precipitation-time-temperature(RPTT) diagrams have been plotted also graphically, which show the Recrystallization-Precipitation interaction. These diagrams show that the effect of the deformation on the precipitation kinetics depends of the microalloy content. In this sense, a new expression is proposed to relate the influence of the deformation and the chemical composition on the minimum incubation of the precipitation kinetics.Peer reviewe

Effects of Nb, V, Ti and Al on Recrystallisation/Precipitation Interaction in Microalloyed Steels

Recrystallisation/precipitation interaction in four steels having Nb, V, Ti, and Al, respectively, as microalloying elements has been studied by means of hot torsion tests. Remarkable differences were found in the results obtained for each steel. Nb and V-microalloyed steels presented long inhibition plateaus, but the steel with Al displayed a very short plateau. Finally the steel with Ti did not show plateau. This means that Nb and V precipitates (nitrides and carbides) can inhibit the static recrystallization but this does not happen for Al and Ti (which form nitrides). The difference between activation energies allows to predict the efficiency of different precipitates to strengthen the austenite during hot rolling. RPTT diagrams showed the interaction between both phenomena, along with the strain induced precipitation kinetics and precipitate coarsening. It is found that AlN particles nucleate and grow faster than NbCN or VN.Peer reviewe

Static Recrystallization of Austenite in a Medium-Carbon Vanadium Microalloyed Steel and Inhibition by Strain-Induced Precipitates

The austenite static recrystallization kinetics at several temperatures and the recrystallization-precipitation-time- temperature (RPTT) diagrams of a medium-carbon vanadium microalloyed steel have been determined for a strain ε = 0.35. Unlike many other studies carried out previously on V microalloyed steels, the recrystallized fraction against time curves showed the formation of a double plateau that indicates two stages of inhibition of recrystallization due to the formation of different types of strain induced precipitates. This work makes use of transmission electron microscopy to study the nature and size distribution of these precipitates capable of inhibiting recrystallization. The values of driving and pinning forces for static recrystallization are calculated and an analysis of the relationship between the net balance of these forces, the precipitation state and the progress or inhibition of the recrystallization is accomplished. A value of driving force that decreases as recrystallized fraction grows during isothermal holding time is estimated and helps to interpret the behavior of austenite after deformation.Peer reviewe

Estrategias de Desplazamiento,Desterritorialización y Reterritorialización en Prometeo Deportado de Fernando Mieles

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Resistencia y subversión en los modelos narrativos de Solange Rodríguez Pappe (Crítica)

This paper studies short stories from the collection La bondad de los extraños (2014) by Solange Rodríguez Pappe. It places the work of this Ecuadorian writer in the in-between spaces of traditional and subversive narrative models from where she operates to propose innovate ways of telling stories. This essay uses a theoretical framework based on science fiction cultural studies that allows highlighting the breadth and depth of the scope of Solange Rodriguez Pappe's writing.El presente trabajo estudia cuentos de la colección La bondad de los extraños (2014), de Solange Rodríguez Pappe. Propone que la obra de la escritora guayaquileña se coloca en espacios intermedios de los esquemas de contar para desde allí resistir a la tradición al mismo tiempo que se nutre de sus logros para proponer maneras que renuevan y avanzan los patrones establecidos. El trabajo emplea un marco teórico basado en los emulados de la crítica de la ciencia ficción desde un acercamiento muy inclusivo que permite resaltar la amplitud y extensión de la manera de escribir de Solange Rodríguez Pappe

El pasado en el presente: La historia en la novela mexicana (1980-1993)

Dissertation (Ph.D.)--University of Kansas, Spanish and Portuguese, 1994.This dissertation analyzes how the Mexican novel (1980-1993) incorporates history. The introductory chapter details the main technical and thematic tendencies of the Mexican novel produced during the 1980's. It also outlines the evolution of the historical novel since Sir Walter Scott to the present marking the changes and transformations of the traditional historical novel to what critics now called, the new historical novel. The latter section of this chapter defines the literary theories employed as the basis of this study, namely, Michel Foucault's discourse, Roberto Gonzalez Echevarria's myth and archive, Linda Hutcheon's historiographic metafiction and Hayden White's metahistory. The second chapter studies novels that incorporate historical events that occurred before the birth of the biographical author: Gonzalo Guerrero (1980) by Eugenio Aguirre, Los pasos de Lopez (1982) by Jorge Ibarguengoitia, Ascencion Tun (1981) by Silvia Molina and La campana (1990) by Carlos Fuentes. Chapter three deals with novels that incorporate recent history, Morir en el golfo (1985) by Hector Aguilar Camin, Charras (1990) by Hernan Lara Zavala and Pasaban en silencio nuestros dioses (1987) by Hector Manjarrez. The fourth chapter includes novels that employ history as narrative strategy, La familia vino del norte (1987) by Silvia Molina and Una pinata llena de memoria (1984) by Daniel Leyva. Chapter five studies a novel written by a historian, Como conquiste a los aztecas (1990) by Armando Ayala Anguiano and compares his emplotment to Cortes' Cartas de relacion. A final chapter provides conclusions and generalizations about the narrative techniques, themes and social and political messages present in novels included under the different groups. This study proposes that the Mexican novel of the 1980's reviews and revises traditional historical accounts, providing new versions of old tales. It gives voice to people who previously could not narrate their version of events. It explores the process of writing history and poses the impossibility of recuperating a faithful account of any event and that we must read versions produced from different perspectives if we wish to obtain a version closer to the truth