Abrasion resistant steel is used in areas where there is likely to be a high degree of abrasion or wear of the steel plate. Typical applications are in truck beds, attachments to diggers and earth movers and in processing applications in the mining industry.400 HB steel is over 3 times harder than mild steel (120HB), but only a third as hard as stainless steel (150HB). Example uses ar... https://www.wearplates.co.in/ar-400-plate-sheets.html