What Is a Wear-Resistant Steel Plate
A wear-resistant steel plate is a quenched and tempered carbon alloy steel developed for components that slide, scrape or impact against hard materials such as rock, ore and abrasive slurries. Unlike ordinary structural steel, the NM series plate is specified by surface hardness rather than yield strength alone, because hardness is the property that most directly controls wear resistance in service.
Hardness Grades and Mechanical Characteristics
The NM series produced to GB/T 24186 covers nominal Brinell hardness levels from 360 HBW to 500 HBW. NM360 and NM400 suit medium wear duty, NM450 offers a balanced combination of hardness and formability, and NM500 is selected where maximum abrasion resistance is required. Every plate is tested on the Brinell scale and supplied with a mill certificate stating hardness, chemical composition and impact properties.
NM360 and NM400 for chutes, hoppers and general liners.
NM450 for buckets, blades and structural wear parts.
NM500 for crusher components and high-impact liners.
All grades offer through-hardness and good low-temperature toughness.
Manufacturing Process
The plates are produced by hot rolling followed by quenching and tempering. Quenching from the austenitizing temperature forms a hard martensitic structure, and tempering then adjusts hardness, toughness and residual stress to meet the target grade. The result is a plate that resists abrasive wear while remaining weldable with appropriate procedures and low-hydrogen consumables.
Typical Applications
Excavator buckets, loader blades and wear liners for earthmoving machines.
Chutes, hoppers and transfer points in mining and cement plants.
Dump truck bodies, crusher feed hoppers and conveyor structures.
Wear plates for mixers, scrapers and bulk handling equipment.
Selection and Quality Assurance
Selection starts with the service condition: the hardness level is matched to the abrasiveness of the handled material and the impact energy involved. Dimensional tolerances, flatness and surface quality are verified before delivery, and each order can be accompanied by material certificates and third-party inspection reports.
Frequently Asked Questions
Q: What does the number in NM400 mean?
The number indicates the nominal Brinell hardness of the plate, so NM400 has a nominal surface hardness of about 400 HBW.
Q: Can NM-series wear plates be welded?
Yes, the plates can be welded using low-hydrogen consumables with controlled heat input, and preheating is often recommended for the harder grades.
Q: What is the difference between NM360 and NM500?
The main difference is hardness: NM500 is harder and more abrasion resistant, while NM360 offers better formability and toughness.
Q: Which standard governs the NM series?
NM-series wear plates are generally supplied to GB/T 24186, the Chinese standard for abrasion-resistant steel plates.
Q: Are the plates supplied with material certificates?
Yes, every delivery includes a mill test certificate with hardness, chemical composition and mechanical test results.