Our 8.8 Grade High-Strength Carbon Steel Hex Head Bolt with Black Oxide Finish is a premium industrial fastening solution manufactured in strict compliance with international ISO 898-1 and DIN standard specifications. As one of the most widely used high-strength fasteners in mechanical manufacturing, steel structure engineering, and industrial equipment assembly, this carbon steel hex bolt features stable mechanical performance, excellent surface treatment, and outstanding assembly adaptability, meeting the high-load fastening demands of various heavy-duty industrial scenarios.
This high-strength hex bolt is made of high-quality medium carbon steel raw materials, which undergoes professional quenching and tempering heat treatment to achieve the standard 8.8 grade mechanical properties. After precise heat treatment, the bolt boasts a minimum tensile strength of 800MPa and a yield strength of 640MPa, with uniform hardness and strong toughness. It effectively resists deformation, fracture, and fatigue damage under high torque, heavy load, and long-term dynamic working conditions, far superior to ordinary grade 4.8 carbon steel bolts in structural stability and service life.
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