GRADE GUIDE · AR400/AR500
AR400 and AR500 are through-hardened wear plates named for their Brinell hardness — roughly 400 and 500 HBW. They are the liner steels of earthmoving and bulk handling: excavator buckets, crusher and chute liners, tipper bodies, and screens that plain structural plate would wear through in months.
Also listed as: AR400 · AR500 · Hardox 400/500 (brand) · 450 HBW grades between · wear/abrasion plate
Stock turns over piece by piece — what's listed is what exists. Post the spec you need and we match it against incoming material; you're alerted the moment something lands.
Wear plate is bought by hardness the way structural plate is bought by yield: AR400 is the workhorse — hard enough to multiply liner life several times over S355, yet still formable and weldable with ordinary care. AR500 pushes hardness further for severe sliding abrasion (crusher liners, high-wear chutes) at the cost of toughness and much stiffer forming. Proprietary names — Hardox 400/450/500 among them — trade in the same category.
Working it takes precautions the hardness demands: plasma or waterjet cutting beats flame (which softens a heat-affected band), welding wants low-hydrogen consumables and controlled heat input to preserve the hardness next to the joint, and AR500 bends only reluctantly over generous radii. Off-cut drops from bucket and body fabricators are ideal liner patch stock — the classic repair-shop purchase, priced per piece with dimensions upfront.
By the abrasion-versus-impact balance: AR400 keeps enough toughness for buckets and bodies that take hits; AR500 wins in pure sliding wear like chute and crusher liners but chips under heavy impact and barely forms.
Only locally — the heat-affected zone softens back toward ordinary plate hardness. Good practice puts welds out of the primary wear path, uses low-hydrogen consumables, and keeps heat input controlled.
It is not produced to a structural design standard — hardness, not guaranteed yield, is the specification. Use it as liner and wear surface over a structural frame, not as the calculated load path.