Cemented carbide bearing balls for rails are spherical parts manufactured using powder metallurgy, primarily composed of high-hardness metal carbide powders such as tungsten carbide (WC), with the addition of binders such as cobalt (Co). They exhibit high hardness, wear resistance, corrosion resistance, and bending resistance, making them suitable for precision bearings, high-speed rail applications, and other applications requiring stringent wear resistance and thermal stability.
I. Material Properties of Cemented Carbide Bearing Balls
High Hardness and Wear Resistance: Cemented carbide bearing balls typically have a hardness ≥90.5 HRA (Rockwell hardness), and their wear resistance is tens to hundreds of times greater than that of traditional steel balls, allowing them to withstand high-load friction for extended periods without significant wear.
Corrosion Resistance and Bending Resistance: The material exhibits high chemical stability, maintaining stable performance in harsh environments such as humid and acidic/alkaline conditions; it also possesses high bending strength, making it resistant to deformation from external impacts.
Thermal Stability: Maintains dimensional stability even under high-temperature environments (such as heat generated by high-speed operation), reducing changes in track clearance due to thermal expansion.
II. Manufacturing Process of Cemented carbide Bearing Balls
Powder Metallurgy Process: Includes steps such as powder preparation, wet grinding and mixing, molding and pressing, and vacuum or high-pressure sintering. By controlling the sintering temperature and time, material density is ensured, eliminating porosity and sand holes.
Precision Machining: Supports rough grinding, polishing, and fine grinding processes, with precision grades reaching G3-G3000 (the smaller the G value, the higher the precision), meeting the stringent requirements of rails for ball dimensional tolerances and surface roughness.
Customization: Can produce special specifications (such as diameters of 0.3mm-60mm) or irregularly shaped balls according to rail design requirements, and supports processing non-standard sizes according to drawings.
III. Application Scenarios of Cemented Carbide Bearing Balls
High-Speed Rail Bearings: Used in bearing systems of high-speed rail, subway, and other rail transit vehicles, bearing the dynamic loads during high-speed vehicle operation, reducing friction loss, and extending bearing life.
Precision instrument bearings: In aerospace, precision machine tools, and other fields, the high precision and stability of cemented carbide balls ensure smooth instrument operation and measurement accuracy.
Heavy-duty industrial equipment: Bearing components in mining machinery and construction machinery utilize their high wear resistance to adapt to heavy-duty, low-speed, and high-impact working environments.
