Mechanical Properties and Microstructure Evolution of an AA5083 via Introducing 0.33%Sc and Cryorolling

Abstract

The influence of Sc on the mechanical properties and microstructure evolution an AA5083 was studied. AA5083/0.33wt%Sc was prepared by stir casting, and then this alloy was subjected to a cryorolling process at-196°C with 50 % rolling reduction. The mechanical properties of the specimens were measured by tensile strength testing and Vickers microhardness test. Furthermore, the microstructure of specimens was analyzed by X-Ray diffraction analysis, scanning electron microscopy (SEM), optical microscopy and electron back scattered diffraction. The ultimate tensile strength (UTS) of the base AA5083 alloy was 238 MPa, which increased to 244 MPa after adding 0.33wt%Sc. After subjecting the as-cast AA5083/0.33wt%Sc to 50% cryorolling reduction, the UTS increased to 404 MPa. The fractured surfaces revealed a large-scale dimpled structure, similar to the ductile fracture mechanism in the starting material. In the cryorolled sample, a fibrous morphology with tiny dimples was observed, corresponding to the low elongation.