Optimum Parameters by Miscellaneous Response Surface of Solid-State Recycling of AA6061 Chips

摘要

This paper deals with the direct recycling AA6061 aluminum alloy milling chips into semi products by the hot extrusion process. The main goal of this study is to obtain mathematical models that will relate the process parameters of a direct recycling to mechanical properties of final semi products. The influence of preheat temperature, preheat time and constant ram speed on Ultimate Tensile Strength (UTS) was investigated using Miscellaneous Response Surface experimental design. The study has shown that the most influential factor on mechanical properties was preheat temperature. Preheat time does not affect on elongation and preheat temperature most influence on ultimate tensile strength. Optical microscopy revealed the cracks and inhomogeneities for all samples extruded on 450 °C in contrast to those extruded on 550 °C which showed no voids or cracks. Optimal recycling process parameters that would give maximal mechanical properties were found.