Correlation of wear behaviour and microstructural evolution in Mg-Zn-Y alloys with long-period stacking ordered phase

The wear properties of extruded Mg-Zn-Y alloys containing a long-period stacking ordered (LPSO) phase were investigated during lubricated pin-on-disc (POD) type tests. The Mg96Zn2Y2 alloy with uneven LPSO-phase layers and alpha-Mg grains, including fine plate-like LPSO phase, exhibited smaller wear mass loss compared to that of the Mg97Zn1Y2 alloy without the fine plate-like LPSO phase. Transmission electron microscopy at the worn subsurface layer revealed that the dynamic crystallisation of the alpha-Mg grains increased the wear mass loss. The presence of a fine plate-like LPSO phase inside the alpha-Mg delayed the dynamic crystallisation of alpha-Mg grains under the lower normal load while it reduced the thickness of the dynamically crystallised layer after sliding deformation under the higher normal load in the Mg96Zn2Y2 alloy.

Automated summary

The wear properties of extruded Mg-Zn-Y alloys with a long-period stacking ordered (LPSO) phase were studied during lubricated pin-on-disc type tests. It was found that the presence of a fine plate-like LPSO phase inside the alpha-Mg grains has effects on wear mass loss and can delay dynamic crystallisation of alpha-Mg grains.