NM500 High-Hardness Wear-Resistant Steel Plate

Product Overview & Manufacturing Standard

NM500 is a through-hardened abrasion-resistant steel plate produced to GB/T 24186 and delivered in the Quenched & Tempered (Q+T) condition. Its nominal surface hardness is 500 HBW with the guaranteed range 470 – 540 HBW, giving a service life 4 – 8 times that of conventional structural steel in severe sliding and impact abrasion.

Typical thickness 4 mm – 100 mm (up to 150 mm on project basis), width 1,500 – 3,200 mm, length 6,000 – 12,000 mm. Plates are supplied shot blasted to Sa2.5 or bare, with size marking, heat number and hardness traceability.

Chemical Analysis (Ladle, % max)

Chemical Analysis (Ladle, % max)

Low carbon-equivalent design with boron micro-alloying for full through-thickness hardening. Each heat is verified by optical emission spectrometry and reported on the mill certificate together with the unique heat number.

Mechanical Properties

Hardness is measured on a milled surface at a minimum of three locations per plate, with one measurement at mid-thickness for plates over 30 mm. Mechanical values are reported per heat on the mill certificate.

International Equivalent Grades

Fabrication & Processing Notes

• Cutting: high-definition plasma, laser or waterjet gives the cleanest edge. Oxy-fuel cutting is possible with 100°C – 150°C preheat for thickness above 20 mm; always machine or grind the cut edge before welding.
• Drilling: carbide-tipped or cobalt alloy (HSS-Co) drills, rigid clamping, steady coolant flow, low cutting speed with positive feed. Laser or plasma-pierced holes are preferred in production.
• Welding: low-hydrogen consumables (H5 / H10) with 150°C – 200°C preheat for thickness above 20 mm; keep heat input below 15 kJ/cm and interpass temperature below 200°C.
• Post-weld heat treatment: not recommended. Exposure above 250°C reduces hardness permanently — design welded joints so that PWHT is not required.
• Forming: cold bending permitted with an inside radius ≥ 6 t transverse to the rolling direction and ≥ 5 t with preheating at 100°C – 150°C. Roll axis should be transverse to the plate rolling direction.
• Surface treatment: shot blasting to Sa2.5 or painting for corrosion protection in damp environments; hardness loss in the HAZ is recovered by using austenitic or low-hydrogen buffer layers.

Typical Applications

• Crusher liners, jaw and cone crusher wear parts, chute and hopper liners
• Shredder hammers, scrap grabs, demolition equipment and shear blades
• Mining dump truck bodies, loader and excavator buckets, bucket cutting edges
• Cement, steel and port bulk material handling systems subject to severe sliding abrasion