Royal Mail decided to look for an alternative material for the deflector plates, and three pairs (front and back) of blades were installed in sorting equipment for a six month trial period. All were 304 stainless steel with one pair being Hard Chrome (HCr) plated, one coated with Hardide-T CVD tungsten carbide coating and one being an uncoated OEM part. The Hardide-T coated parts processed 50% more items than the HCr plated part and 255% more items than the OEM parts. In all three sets, the front blade was more affected than the rear so comparative analysis was carried out on the front blades to analyse the more severe wear effects.
A visual examination showed that the highest levels of wear were apparent on the OEM part where the material had completely broken down. The HCr plated part showed some signs of wear and the Hardide-T coated part looked as new, despite the much higher item throughput.