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NM400 and NM500 are high-strength wear-resistant steel plates ("N" and "M" come from the Pinyin of "wear-resistant" in Chinese, and 400/500 represent their Brinell Hardness values); they are widely used in engineering machinery to make excavator bucket plates, loader blades and bulldozer edge plates (withstanding intense wear and impact to extend service life), in mining machinery to produce crusher liners and conveyor liners (enhancing equipment reliability in harsh ore environments), while NM400 is also applied in construction (high-rise building structural parts), automotive (body and chassis components) and metallurgy (blast furnace grates), and NM500 in environmental protection machinery, molds and coal mill liners, ensuring durability in wear-prone scenarios like power plants, cement plants and coal yards.