Sharpness of abrasive particles and surfaces

The concept of asperity sharpness has recently been developed into a technique for the description of abrasive particle shape. This paper reveals further discoveries on the nature of particle shape and applies sharpness concepts to nominally planar abrasive surfaces composed of self-arranged particle stacks. The main purpose of the investigation is to determine whether there are any significant changes of surface shape that are dictated by particle size; thus establishing to what extent particle stacking influences the well known particle size effect. In pursuing this objective it has been found that the average shape of particle asperities can be conveniently modelled by a power-law—this useful discovery simplifies the description of abrasive particle shape. In addition, when particles are affixed to a planar substrate, the resulting surface exhibits unique properties that are convenient for surface characterisation and the development of abrasion models. The behaviour of these surfaces is investigated in relation to the underlying particle properties. The serial sectioning technique used to investigate the abrasive surfaces is described in this paper and preliminary results are also presented.