Formation of fine multicomponent precipitates and enhanced precipitation-hardening in an Al-Cr-Pr-Zr alloy

Abstract

The microstructure of the Al-1.0Cr-1.4Pr-1.6Zr (mass%) alloy after homogenized at 500°C for 400 h has been investigated. Addition of Cr, Pr and Zr in combination into pure aluminum results in the formation of submicron Zr-containing PrCr2Al20 and nanoscale Cr, Pr-containing Al3Zr dispersed phases. Compared with the Al-1.0Cr-1.4Pr and Al-1.6Zr alloys, a denser distribution of new fine multicomponent dispersed phases and their superimposition effect are associated with enhanced precipitation- hardening behavior of Al-1.0Cr-1.4Pr-1.6Zr alloy. © 2013 The Japan Institute of Light Metals.