Effect of Ge addition on the clustering of naturally-aged Al–Mg–Si–Cu alloy

Abstract

Ge addition effect on the delaying natural aging of Al–Mg–Si–Cu alloy was investigated. Natural aging kinetic and cluster size was suppressed by the Ge addition. Using atom probe tomography, it was found that Ge refines cluster evolution by disturbing Mg-enrichment of Si–Si cluster as well as enhancing vacancy trapping. Segregation of Ge at the interface of cluster was also regarded as potential barrier to growth of the clusters.

Keywords

• Aluminum alloys
• Precipitation
• Microalloying
• Trace element
• Natural aging