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NM400 and NM500 steel bars are widely used in engineering machinery for manufacturing excavator bucket teeth, loader ripper tips, and bulldozer blade shafts, as their high hardness and wear resistance can endure intense impact and friction during operation to extend component service life. In mining machinery, they are applied to produce crusher jaw plates, conveyor idler shafts, and ore hopper support rods, effectively enhancing equipment reliability and stability in harsh ore-extraction and transportation environments. NM400 steel bars also find use in the construction field (for wear-resistant drill rods in foundation engineering) and metallurgical industry (for high-temperature furnace door guide rails), while NM500 steel bars are suitable for coal mining machinery (coal cutter pick holders) and environmental protection equipment (waste crusher rotor shafts); both types ensure durable performance in wear-prone scenarios such as power plants, cement plants, and coal yards.