Microhardness measurements were performed on the cut section of the 2196-T8511 Al-Li alloy specimens
using a FEM-8000 automatic micro-hardness measuring instrument, applying a maximum force of 10 gf with a
dwell time of 6s. Firstly, a good cross-section metallographic sample preparation, the samples were gradually
measurements from the surface to the core part. Secondly, intense deformation zone and the transition zone were
measured once every ȝP then increased the measurement step length until the base material. Three
measurements were performed at each depth and the average value was used to plot microhardness distribution
curve.