High-productivity, field-relevant assessment of relative fracture resistance for hard materials – The ball mill edge chipping test (BMECT)

Abrasion-resistant materials for rock-facing applications typically display low fracture toughness. For materials selection, available fracture data are limited, due to the cost of testing. To address this shortage, a new type of fracture test, denoted the ball mill edge chipping test (BMECT), has been designed. The device is derived from the ball mill abrasion test (BMAT) [37]. It uses simple block or ball specimens with machined edges. Specimens of multiple materials are tested simultaneously. Collisions promote multiple small-scale fracture events at the exposed edges, causing progressive volume loss. The reciprocal of volume loss indicates relative fracture resistance.This paper analyses the BMECT’s relevance to service, and explores its capacity to generate data at low cost. Several data sets are presented, illustrating its application to investigate factors affecting fracture resistance among common abrasion-resistant materials. The results demonstrate multiple advantages over traditional fracture tests — including low cost, high sensitivity to differentiate between materials, and close replication of in-service damage modes. It represents a fundamentally new approach to fracture resistance assessment. Whereas traditional tests are regarded as deterministic, the BMECT is stochastic, providing potential for superior statistical data quality.