Estudo das alterações das propriedades mecânicas em aço A-516 grau 70 soldado e submetido a tratamento térmico de alívio de tensões

Pressure vessels are equipments that require a great care because of their high cost and human life risk in case of fail, and its fabrication methods are different for each manufacturer. Normally, pressure vessels and its parts are fabricated by welding, which may change local properties of metals. The head of a pressure vessel is a very important structural component and it is fabricated by welding and mechanical conformation. Because its excellent mechanical properties, de steel A-516 Grade 70 is often used in manufacturing of large pressure vessels that are subjected to high pressure and temperature, but was verified that its mechanical resistance is decreased when submitted to a tension relief heat treatment. By experience it was defined that before mechanical conformation of the head of a large pressure vessel, the steel should be submitted to a stress relief heat treatment in order to facilitate the mechanical conformation, but there is no quantitative analysis to prove this method and study its possible risks. In the present work the steel A-516 Grade 70 demonstrated a decrease of its mechanical resistance when submitted to a stress relief heat treatment, but keeping above the minimum limit defined in the literature. By other side its ductility was substantially increased, being possible to deduce that the stress relief heat treatment before mechanical conformation is a viable e recommended technique, but with reservations. With the data acquired during the fabrication e preparation of the specimen and the result of the tests, it was possible to elaborate a welding procedure that provides the same results obtained in this present work

Controle ativo de estruturas reticuladas utilizando atuadores de pilha de pzt

Pós-graduação em Engenharia Mecânica - FEIS

Equipamento para realização de ensaios de tração confinada e aquecida em geossintéticos

Pós-graduação em Engenharia Civil - FEIS

Avaliação da qualidade de vida de pacientes portadores de hepatopatias

Pós-graduação em Odontologia Preventiva e Social - FOA

Desenvolvimento de sistema eletrônico para instrumentar um DPL em ensaio dinâmico de resistência do solo

Pós-graduação em Engenharia Elétrica - FEIS

A política como incômodo

This article holds that the dominant scene of the “crisis of politics” in modern societies reflects a complex process of reconfiguration of social life and way of living. Through critical dialogue with some representatives of political sociology of radicalized modernity, it suggests that current failure of politics is the failure of one way of doing and thinking about politics, direct heir of “historical capitalism”. It is not the failure of politics as such, but of a mode of politics, political system, political practice. It must be associated with a sort of fatigue of the material which composed modern politics, which has always been based on strong national and constitutional states, on mass parties and active parliaments, as well as on the efficient functioning of representative democracies.