Estudo do processo de laminação transversal com cunha (cross wedge rolling) para fabricação de eixos escalonados




ln this work tests were held with the Cross Wedge Rolling (CWR) process to analyze the influence of the process temperature, process speed and properties of the workpiece materiaJson the stability of the process. To perform these tests it was necessary to design and assemble a laboratory CWR equipment flexible enough to manufacture shafts with large ranges of diameters and strain rates, with a pak of flat tools able to roll parts free of defects in accord to stability diagrams found in the literature for CWR process. Three different alloys were tested: a commercial aluminum alloy, ABNT 4140 steel and the microalloyed steel 48MnV3. This microalloyed steel was chosen because of its mechanical properties are similar to those necessary to manufacture stepped shafts. The shafts rolled with this steel were analyzed measuring the internal defects, Rockwell C hardness and perform metallographic analysise valuating their macro and microstructures. Results showed that the Hayama stability diagram, that are used to design CWR tools, are not representative of this process because they do not consider the properties of the workpiece material in the correct way. The results also showed that higher temperatures reduce the probability of internal defects formation, rise the grain size, the perlite volume ftaction and hardness, but no conclusions can be made relating these defects an structures with the variation of the process speed


metal-rolling laminação (metalurgia) - defeitos cross wedge rolling aço laminação (metalurgia)

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