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.