Characterisation of aggregate notch cavity formation properties on abrasive waterjet cut surfaces

Aggregate induced notch cavity formations were observed to have formed on the surface of abrasive waterjet cut edges. The secondary micro-machining effect of the abrasive waterjet has been observed to plastically deform grains in proximity to the cut-edge. This interaction governs the operative mechanism of material removal and resulted in the formation of notch cavities on the cut surface. Controlling the traverse cutting speed was found to be critical towards influencing kerf perpendicularity which influences the characteristics and quantity of notch cavity features and the deposition of nanometer sized particles of aggregate. It is shown that the surface waviness properties are reduced as the traverse speed is increased and there is an association between the surface properties and the plastic deformation of the microstructure.

► The mechanisms behind the formation of notch cavities during the AWJ cutting process are understood.
► The mechanisms notion that connect surface and internal features have been further developed.
► The effect of the AWJ jet on the microstructural properties of steel has been established.