A new technique for measuring particle angularity using cone fit analysis

The classical abrasion model, proposed by Rabinowicz, is founded on the premise that abrasive surfaces are composed of protrusions that are approximately conical. This premise is supported by Kruschov’s experiments which show that the wear resistance of pure metals in two body abrasion is linearly related to hardness. This leads to an important question — do most abrasive types exhibit conical behaviour or is it coincidental that the abrasives used by Kruschov conformed to the idealised model? To answer this question, a new particle characterisation technique has been developed. By fitting cones to projected particle profiles at different penetration depths, it is possible to judge how closely the protrusions resemble cones. This technique is also useful for assessing the directional properties of particles and characterising the angularity of particle samples in relation to wear rate. The technique has been called cone fit analysis (CFA) — its development and application are discussed in this paper, together with an experimental assessment of some common types of abrasive particles.