Near net shaped casting of heattreatable Al-Zn-Mg-Cu wrought alloy by controlled diffusion solidification (CDS) process: Microstructure, mechanical properties and heat treatment

In Controlled diffusion solidification (CDS), two differently thermal mass precursor alloys are mixed and subsequently the resultant mixture cast into near net shaped cast component. The CDS process enables casting of the Al wrought alloys into near net shaped components by mitigating the problem of hot tearing through ensuring a non-dendritic morphology of primary Al-phase. The study presents the favorable process and alloy parameters for sound shaped casting of 7xxx Al-wrought alloy (Al-Zn-Mg-Cu-(Si)), namely, 7068, 7050 and 7075, by the CDS process along with the mechanical tensile properties under various heat treatment conditions. The tilt pour gravity casting process was used for this study to demonstrate the ability to cast high integrity components with high strength and ductility. In depth microstructure analysis outlining the phased in the cast and heat treated microstructure would also be presented. Copyright © 2013 MS&T'13®.