The literature contains reports of several studies correlating the porosity and mechanical properties of aluminum alloys. Most of these studies determine this correlation based on the parameter of global volumetric porosity. These reports, however, fail to separate the effects of microstructural features and porosity on alloys, though recognizing the influence of the latter on their mechanical properties. Thus, when the decrease in tensile strength due to the porosity effect is taken into account, the findings are highly contradictory. An analysis was made of the correlation between mechanical properties and global volumetric porosity and volumetric porosity in the fracture, as well as of the beta-Al5FeSi phase present in 380 aluminum alloy. Our findings indicate that mechanical properties in tension relating to global volumetric porosity lead to overestimations of the porosity effect in detriment to the mechanical properties. Moreover, the proposed models that take into account the effects of particles, both Si and beta-Al5FeSi, are unapplicable to low ductility alloys

No abstract

ResumenCon el objeto de mejorar la trabajabilidad de aleaciones CuNiSiCr se realizó un estudio de las condiciones del tratamiento térmico de homogeneizado y se evaluó su comportamiento mecánico a través de ensayos de tracción. Se realizaron ensayos de homogeneizados a 850, 950 y 1025ºC con tiempos de mantenimientos de 0, 1,5 y 6 horas y un posterior doble envejecido. Sobre ese material se realizaron ensayos de tracción a temperatura ambiente. Los resultados muestran una importante mejora en la trabajabilidad para temperaturas de 850ºC y tiempos de homogeneizados de 6 horas. Esta mejora en la ductilidad está asociada a la presencia de una microestructura conteniendo una escasa cantidad de precipitados discontinuos en límite de grano y precipitados redondeados en el interior de los granos. Se concluye que el tratamiento térmico de homogeneizado es una herramienta adecuada para aumentar la trabajabilidad de la aleación. Palabras clave: aleación CuNiSiCr, tratamiento térmico, homogeneización, crecimiento de grano, ductilidad Effects of Homogenization Treatment on the Workability of Alloy CuNiSiCr AbstractIn order to improve the workability of alloys CuNiSiCr a study of the conditions of homogenizing heat treatment and assessed their behavior through mechanical tests traction. Standardized tests were conducted at 850, 950 and 1025ºC with time-keeping 0, 1.5 and 6 hours and a subsequent double aged. It was observed that the optimum workability for the alloys occurs at the 850ºC and 6 hours. This improvement in ductility is associated with the presence of a microstructure containing a small amount of discontinuous precipitates in limiting grain and rounded precipitates inside the grains. It is concluded that the homogenizing heat treatment is and adequate method to increase the workability of the alloy.

No abstract