The difference between ordinary bolts and high-strength bolts?

Ordinary bolts are generally made of ordinary carbon structural steel without heat treatment, and high-strength bolts are generally made of high-quality carbon structural steel or alloy structural steel, which requires quenching and tempering heat treatment to improve comprehensive mechanical properties. High strength is divided into 8.8 grades, 10.9 grades, and 12.9 grades. From the strength level: Two strength levels of 8.8S and 10.9S are commonly used for high-strength bolts. Ordinary bolts generally have grades 4.4, 4.8, 5.6 and 8.8. From the force characteristics: High-strength bolts apply pre-tension and transmit external force by friction, while ordinary bolts transmit shear force by the shear force of the bolt rod and the bearing of the hole wall.