40Cr steel mechanical hub bolts (wheel studs) are high-strength fasteners designed for automotive wheel assembly applications. These precision-engineered components provide reliable torque transmission and secure wheel mounting for various vehicle types.

• Material: 40Cr steel with excellent mechanical properties
• Strength Grades: 4.8, 8.8, 10.9, 12.9 available
• Common Shapes: T-bolt head, stud with pad configuration
• Surface Treatments: Blue/white galvanized, dazzle galvanized
• Hardenability: Water quenching to Ф28-60mm, oil quenching to 15-40mm
• Cutting Performance: 60% relative machability at 174-229HB hardness

40Cr steel offers superior comprehensive mechanical properties after quenching and tempering processes. This material provides excellent low-temperature impact toughness, minimal notch sensitivity, and is suitable for cyaniding and high-frequency quenching treatments, making it ideal for medium plastic mold applications.

T-head hub bolts (grade 8.8 and above) handle high-torque connections between car hubs and axles, while double-headed hub bolts (grade 4.8 and above) manage light-torque connections between outer hub shells and tires. Micro vehicles typically use grade 10.9, while large and medium-sized vehicles require grade 12.9 strength levels.