AR400 Steel: wear plate properties, cutting, and fabrication FAQs
Top 5 must-know things about AR400
- AR400 is a quenched-and-tempered abrasion-resistant steel with nominal ~400 HBW hardness built to resist wear, sliding abrasion, and repeated impact.
- Sits below AR500 in hardness, but is easier to fabricate (cutting and limited forming) and often a better fit for wear liners and structural wear parts.
- SendCutSend laser cuts AR400 for clean edges and tight tolerances (±0.005″).
- Excellent for wear plates, buckets, chutes, off-road skid plates, and industrial tooling exposed to abrasion.
What is AR400 steel?
AR400 is part of the abrasion-resistant (AR) family of steels engineered for high wear environments. The “AR” denotes abrasion resistance; the “400” indicates a nominal 400 Brinell hardness. Through quenching and tempering, AR400 achieves a mix of hardness, strength, and toughness that outlasts mild steels in sliding or gouging wear. It’s a workhorse for liners, wear strips, and impact faces in heavy-duty service.
At SendCutSend, AR400 is precision laser cut so you can go straight from CAD to durable, production-ready wear parts.
What does “AR400” mean, and how hard is it?
“AR400” is shorthand for an abrasion-resistant steel engineered to achieve about 400 HBW hardness. Real-world plate often lands in a window (roughly 360–440 HBW), balancing surface hardness for wear with enough ductility to survive impact without shattering. This balance is why AR400 is a common choice for wear plates that still see bending or shock.
What are the material properties of AR400?
Property values vary by mill and thickness, but AR400 generally targets:
- Hardness: ~360–440 HBW (nominal “400”)
- Tensile strength: commonly in the 170–190+ ksi range
- Yield strength: typically > 140 ksi
- Elongation: lower than mild steel; depends on thickness/heat treatment
- Density: ~0.283 lb/in³ (steel baseline)
The key takeaway: AR400’s elevated hardness and strength deliver much longer life under abrasion than A36 or similar mild steels.
Can AR400 be laser cut? What methods work best?
Yes, fiber laser cutting is an excellent method for AR400, and it’s how SendCutSend produces clean, repeatable parts:
- Tolerances: we hold ±0.005″ on laser-cut parts.
- Edge quality: smooth, minimal dross, tight kerf that is ideal for holes, slots, and detailed profiles.
- Heat input: lower and more localized than plasma/oxy-fuel, helping preserve base properties away from the edge.
DIY cutting tools (abrasive saws, consumer plasma) tend to leave rough edges, wider kerfs, and larger HAZ—which can soften the steel where you need it hardest.
What edge condition / HAZ effects occur when cutting AR400?
All thermal cutting creates a heat-affected zone (HAZ) In AR steels, the HAZ can modify hardness: plasma/oxy-fuel often produce wider, softer edges; fiber laser cutting keeps the HAZ narrow so the base hardness is better preserved. Where edge hardness matters (e.g., wear lip), laser cutting is a strong choice.
What are typical applications where AR400 shines?
AR400 is ideal for anywhere steel slides, scrapes, or gets pounded:
- Wear liners & wear bars: chutes, hoppers, conveyors, buckets.
- Off-road/industrial armor: skid plates, rock guards, protective panels.
- Agricultural/mining/construction: blades, scraper edges, impact plates.
- Tooling & fixtures: where long-life surfaces reduce downtime.
If you’re replacing mild-steel plates frequently, AR400 often cuts maintenance cycles and total cost of ownership.
How does AR400 compare to AR500 (and other AR grades)?
- Versus AR500: AR400 is softer but more forgiving—generally easier to process and less crack-prone in limited forming. AR500 offers higher surface hardness (better for extreme impact/target faces) but is less formable and tougher to weld.
- Versus AR450/AR460: incremental steps up in hardness; choose based on wear severity versus fabrication needs.
- Versus mild steel (A36): AR400 dramatically outlasts A36 Mild Steel in abrasion but is less ductile and more demanding to weld/form.
Rule of thumb: pick AR400 when you need durability + workable fabrication; pick AR500 when maximum surface hardness is the priority and forming is minimal.
When should you fabricate AR400 yourself vs outsource to SendCutSend?
You can cut AR400 in-house with industrial equipment, but the usual DIY routes (abrasive saws, consumer plasma) lead to slow cutting, tool wear, wide kerfs, and large HAZ. Precision holes/slots and fine features are especially tricky.
Outsourcing to SendCutSend delivers:
- ±0.005″ laser-cut accuracy with crisp geometry.
- Narrow HAZ to better preserve wear properties at the edge.
- Fast turnarounds (parts typically ship in 2–4 days).
For most teams, outsourcing reduces consumables, rework, and schedule risk while improving consistency.
Conclusion
AR400 hits a versatile sweet spot for abrasion-resistant wear parts: hard enough to dramatically outlast mild steel, yet workable enough to integrate into real-world assemblies with controlled welding and limited forming. With fiber-laser precision (±0.005″), narrow HAZ, and fast 2–4-day turnarounds, SendCutSend makes it straightforward to turn your CAD into durable liners, guards, and skid plates.
