Surface nanocrystallization of magnesium alloy AZ91D by high-energy shot peening

Abstract

High-energy shot peening (HESP), a method to produce severe plastic deformation by high velocity flying balls, was applied on die cast magnesium alloy AZ91D. Effects of surface nanocrystallization by HESP and heat treatment at different temperatures were investigated. The microstructure evolution was conducted using X-ray diffraction (XRD) and field emission scanning electronic microscopy (FESEM). The hardness was measured by microhardness tester. The experimental results show that surface nanocrystrallization of AZ91D obtained by HESP would lead to the increase of microhardness. Low temperature heated at 100 °C for 1 h do not change the property obviously. However, both the microstructure and microhardness vary greatly after heat treatment at 400 °C for 1 h.

Keywords

AZ91D / surface nanocrystallization / HESP / microhardnss / corrosion resistance

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