NM550 vs NM500
These two grades are listed as equivalents of each other: their chemistry windows overlap and they serve the same applications. They are not always identical — check the differences below before substituting, especially in certified designs.
NM550
Wear-Resistant Plate
NM550 is the 550 HBW member of the GB/T 24186 family, aimed at extreme sliding abrasion where NM500 wears through too fast. The cost is toughness: it is a liner material, not a forming or impact material.
Standards: DIN — (cf. XAR550 class) · AISI AR550 class · GB NM550 (GB/T 24186)
NM500
Wear-Resistant Plate
NM500 is the 500 HBW abrasion-resistant plate for severe wear: roughly double the service life of NM400 in sliding abrasion, at higher forming and welding demands.
Standards: DIN — (cf. XAR500 class) · AISI AR500 class · GB NM500 (GB/T 24186)
Chemical composition compared (%)
| Element | NM550 | NM500 |
|---|---|---|
| C | ≤0.32 | ≤0.30 (typ.) |
| Si | ≤0.70 | ≤0.70 |
| Mn | ≤1.60 | ≤1.60 |
| P | ≤0.025 | ≤0.025 |
| S | ≤0.010 | ≤0.010 |
| Cr | ≤1.50 | ≤1.50 |
| Ni | ≤1.00 | ≤1.00 (typ.) |
| Mo | ≤0.65 | ≤0.65 |
| B | ≤0.004 | ≤0.004 |
Properties compared
| Property | NM550 | NM500 |
|---|---|---|
| Hardness | 520–580 HBW | 470–540 HBW |
| Tensile strength | ≥1500 MPa (typ.) | ≥1450 MPa (typ.) |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
Sourcing either grade?
Nasteel stocks both families from Shenzhen with EN 10204 3.1 mill certificates by heat number.
Ask for a quotationSee full data sheets: NM550 · NM500. Substitution decisions for certified parts stay with the design authority.