Investigating the effect of different adhesion materials on electrical resistance using a high pressure torsion rig

This paper presents an assessment of newly-developed conductive adhesion materials (Products A-E) in comparison to standard rail sand used in Britain. Current rail sand is an insulating material which can affect track circuits; newly-developed conductive materials could reduce the risk of this and allow for more material to be applied to further mitigate against low adhesion. The particles were characterised to determine their densities, and size and shape distributions. Bulk behaviour was assessed through three characteristics: angle of repose, bulk shear strength, and particle breakage index. Materials were then assessed using a high pressure torsion approach to measure their effects on adhesion and electrical resistance in dry, wet, and leaf contaminated conditions. It was found that all products produced better or equivalent conductivity compared to the currently used GB rail sand and that Product D and Product E should be considered for future field testing.