Thixoformability evaluation of AA2011 and AA2014 alloys

This paper examines the feasibility of thixoforming two commercial aluminum copper alloys: AA2011 and AA2014. This evaluation was performed in three steps: 1) characterization of the raw materials, including an analysis of their constituents, partial melting range temperatures, and microstructures; 2) characterization of the samples' morphological evolution during partial melting to observe their globularizadon at two different sets of temperatures, (solid fractions of 45% and 60%), and four holding times: 0, 30, 90 and 210 s; and 3) tests of the morphological behavior under the same partial melting conditions of temperature and holding times. The results indicate that, despite the difficulty of controlling the temperature of the semi-solid transition, these two alloys are suitable for thixoforming processes. Their morphology is stable in the semi-solid range and the corresponding viscosity values are lower than 10(6) Pa . s, resulting in a maximum conformational stress of 2.4 MPa.