Every mine and quarry burns through liner plate — the only question is how fast. Choosing between AR400 and AR500 abrasion-resistant plate is a trade between wear life, formability and weldability, and the right answer depends on which failure mode is actually killing your components.
What the numbers mean
The AR number is nominal Brinell hardness: AR400 plate is quenched to roughly 360–440 HB, AR500 to roughly 460–540 HB. Hardness resists sliding abrasion — rock scraping across a surface — so as a first approximation, moving from AR400 to AR500 buys meaningfully longer life in high-slide applications. But hardness trades against toughness and workability, which is why the harder grade is not automatically the better buy.
Where AR400 is the right call
- Formed parts — bucket wrappers, chute transitions, anything press-braked. AR400 bends with sensible radii; AR500 fights the brake and may crack.
- Impact-heavy service — primary crusher areas and dump points where plate takes repeated shock as well as slide. AR400’s extra toughness resists cracking and spalling.
- Welded fabrications — AR400 welds with standard low-hydrogen practice and reasonable preheat; AR500 demands more care.
Where AR500 pays for itself
- Sliding-dominated wear — truck body floors, discharge chutes, hopper liners, screen underpans where material flows across the plate.
- Bolt-on liner packages — flat or simply-cut liners that need minimal forming and welding.
- Downtime-driven economics — where a liner change costs more in lost production than in steel, the harder grade’s extra service life wins even at a higher plate price.
Many operations standardize on both: AR400 for formed and welded structures, AR500 for flat sacrificial liners. That is the pattern our mining customers in Australia and South America follow.
Buying wear plate sensibly
Specify by hardness range, thickness and pattern list, not brand names — AR grades are generic classifications produced by many certified mills. Ask for the hardness certification with the shipment: CSACI supplies wear plate with a Certificate of Conformity stating chemistry and Brinell hardness, a Certificate of Origin, and SGS third-party international inspection. Plate ships as mill sheets or cut-to-pattern liner kits; see the wear plates range for scope.
Quick answers
Can AR500 replace AR400 one-for-one? For flat liners, usually yes. For formed or heavily welded parts, review the fabrication first.
Is thicker AR400 better than thinner AR500? Sometimes — in impact zones, added section absorbs energy that hardness alone cannot. In pure slide zones, hardness beats thickness per dollar.
What is the minimum order? 100 metric tons — typically a mixed pattern list across thicknesses and grades, which we consolidate into one shipment with your structural steel if useful.
Send your liner list — grades, thicknesses, patterns, tonnage — for a quotation typically within 1–3 days: request a quote.