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This work evaluates the morphological evolution at the semisolid state of the Al-4.0wt%Si-2.5wt%Cu alloy produced by direct chill casting under electromagnetic stirring (EMS) and by one equal channel angular pressing (ECAP) pass. The ECAP emerged as a promising technique capable of reduction and homogeneous metals microstructure imposing large deformations occurs in a matrix that contains two channels of the same cross-sectional area and forms an angle of 120°. The materials were submitted to reheating treatment in condition of 60% solid fraction at treatment times of 0, 30, and 90 s. Comparing the two cases, we have the presented ECAP process that had an excellent response to the recovery and recrystallization mechanisms, and refined microstructures ideal for thixoforming were produced. Primary particle sizes of about 45 μm and grain sizes of about 75 μm and a circularity shape factor of more than 0.60 were obtained. The low silicon alloy, Al-4.0wt%Si-2.5wt%Cu, presented excellent refinement when processed via equal channel angular pressing, presenting good morphological stability at the semisolid state, without significant changes in size or shape of the solid particles. This fully globular structure is favourable for thixoforming processes.

Presidente de la Corporación Autogobierno y Democracia F.A. Hayek que publica la Revista Debate Constitucional. Autor del libro "Presidencialismo Constituyente". www.cad.org.ec Resumen:Ante el vehemente avance de los postulados neoconstitucionalistas, tanto en el ámbito normativo constitucional formal, cuanto en las actuaciones de jueces constitucionales, nos encontramos en un nuevo escenario, marcado por el denominado activismo judicial. Alejados de la aplicación de normas o reglas, la aplicación de principios y valores, constituyen herramientas poderosas puestas a disposición de jueces y que tiene el potencial de resultar en una marcada discrecionalidad, que a su vez puede poner las decisiones judiciales al servicio de intereses o ideologías. Considerando la innegable realidad del panorama jurídico nacional, cabe analizar también las connotaciones de la constitucionalización del derecho privado, como reafirmación de la transversalidad del Estado en la sociedad y como amenaza a las libertades individuales. AbstractFacing the intense advancement of neoconstitutionalism statements, not only in the constitutional regulation, but also in the actions of constitutional judges, we are in a new stage, marked by the so called judicial activism. Far from the application of standards or rules, the application of principles and values,gives judges a powerful tool that can result in a marked discretion, which in turn can make judicial decisions to service private interest or ideologies. Considering the undeniable reality of the national legal scenery, it is also important to analyze the connotations of the constitutionalization of private law, as a reaffirmation of the mainstreaming of the state in society and a threat to individual liberties.Sumario:

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