Chinese Hard Wear-Resistant Steel Plate

In heavy industries, wear-resistant steels are of great importance. One of the most widely used types of these steels is the Hardox plate. These plates, with very important features such as: high hardness, resistance to wear and impact, are used in various industrial projects. Alongside reputable European brands such as SSAB, Chinese manufacturers have also captured a large share of the market by offering wear-resistant plates under the title of Chinese Hardox plate or NM plate, short for “Nai Mo (耐磨)” meaning “wear resistant.”
Chinese Hardox plates are available in various grades such as NM400, NM450, and NM500, and each of these grades is designed for a specific application.

Chemical Composition of NM Plates

Chinese Hardox plates are made from a special combination of alloying elements that increase hardness and wear resistance. This chemical composition is such that, in addition to wear resistance, it offers high tensile strength and good weldability. The approximate chemical composition of Chinese Hardox plates is shown in the table below:

Element Amount (%)
Carbon (C) 0.25% - 0.35%
Silicon (Si) 0.60% - 0.80%
Manganese (Mn) 1.40% - 1.80%
Chromium (Cr) 0.80% - 1.20%
Molybdenum (Mo) 0.20% - 0.35%
Nickel (Ni) 0.20% - 0.40%
Phosphorus (P) ≤ 0.020%
Sulfur (S) ≤ 0.010%

Mechanical Properties of Chinese Hardox Plates

Chinese Hardox plates have different hardness levels depending on the grade, making them suitable for various applications. The table below presents the mechanical properties of NM400, NM450, and NM500 grades:

Grade Hardness (HBW) Tensile Strength (MPa) Elongation (%) Impact Resistance (J) at -20°C
NM400 ~400 1250 – 1350 14 ≥ 50
NM450 ~450 1350 – 1450 12 ≥ 45
NM500 ~500 1450 – 1600 10 ≥ 40

These features make NM plates highly suitable for use in environments with severe

abrasion or impact conditions.

1. NM400 Plate :

NM400 plate has lower hardness and is suitable for applications with moderate wear. Its applications include:

  • Trailer and dump truck floors: NM400 is very suitable for vehicles transporting heavy materials.
  • Loader and excavator walls: These plates are used in construction and mining machinery under pressure and wear.
  • Conveyor belt plates: In industries using conveyor belts to transport minerals and heavy materials, NM400 resists abrasion.

2. NM450 Plate :

NM450 plate has higher hardness and is suitable for applications requiring higher resistance. Its applications include:

  • Inner walls of crushers: NM450 is used in crushers to resist severe wear from hard materials.
  • Liners of tanks and hoppers: Used in structures exposed to severe impact and wear, such as tanks and hoppers.

3. NM500 Plate :

NM500 has the highest hardness among Chinese Hardox plates and is suitable for applications requiring very high wear resistance. Its applications include:

  • Bulldozer blades and graders: NM500 is used in parts of heavy machinery such as bulldozers and graders.
  • Crusher hammers and mills: Ideal for mining equipment exposed to severe impact and wear.

Advantages of Chinese Hardox Plate

  • More affordable compared to Swedish Hardox plates.
  • Variety of grades: NM400, NM450, and NM500 are produced for different applications.
  • Suitable quality for industrial conditions in Iran.
  • Resistance to wear and impact under harsh environmental conditions.
  • Good weldability and machinability.

Comparison with Swedish Hardox Plate

While Swedish Hardox plates (SSAB) have higher quality and more precise control, Chinese Hardox plates remain a cost-effective option for industries. The following is a simple comparison between the two:

Feature Chinese Hardox (NM) Swedish Hardox (SSAB)
Surface Quality Good Excellent
Price Lower Higher
Quality Consistency Moderate Very High
Technical Certificates Available Complete and Internationally Valid

SSAB STEEL SAZEH Company, as one of the reliable suppliers in the field of steel and stainless steel plates in Iran, has achieved a trusted position in supplying various stainless steel sections and alloy plates such as Hardox, Weldox, and A387 plates.
With direct and unmediated imports from China and continuous cooperation with reputable manufacturers, the company has succeeded in ensuring product quality while providing competitive pricing and fast delivery.
SSAB STEEL SAZEH, with a deep understanding of the needs of Iran’s strategic industries including oil, gas, petrochemical, food, medical equipment, mining, heavy machinery, and metal industries, is ready to offer specialized services, technical consulting, and continuous supply for industrial projects across the country.