Abrasion resistant steel is a high-carbon alloy steel that is produced to resist wear and stress. There are several grades of abrasion resistant steel, including AR200, AR235, AR400, AR450, AR500 and AR600.[1]
Abrasion resistant steel undergoes a two-step heat treatment process called quenching and tempering, which alters the steel's grain structure to increase hardness and toughness.[2]
During the quenching phase, the steel is heated to an above-critical temperature and is then rapidly cooled with water. The steel is then re-heated to a below-critical temperature and air cooled, which is the tempering phase.
The hardness of abrasion resistant steel is determined by a Brinell hardness test. This test uses a small steel ball to inflict force on a material. The indentation created by the steel ball is then measured and used to calculate Brinell hardness number (BHN).[3]
| Grade | BHN | |
|---|---|---|
| AR200 & AR235 | 180-260 | |
| AR400 | 360-440 | |
| AR450 | 430-480 | |
| AR500 | 460-544 | |
| AR600 | 570-625 |
Standards for Brinell hardness testing are regulated by ASTM International under E10 specifications.[5]
Abrasion resistant steel is typically used in applications requiring high wear resistance, including backhoe buckets and teeth, bulldozer blades, dump truck beds, ore and coal chutes, augers and aggregate conveyors.[6] Additional uses include shooting targets and armor, AR500 steel is commonly used for these applications as higher BHN steels are more brittle.[7]