10B21 can do as big as 8.8 class bolts

10B21 is a common carbon steel material, commonly used to make bolts, screws and other fasteners. Class 8.8 is a sign indicating the strength level of the bolt, indicating that the minimum tensile strength of the bolt is 800MPa, and the minimum tensile strength is 0.8 times the yield strength. According to the specification,8.8 class bolts are usually made of carbon steel materials, common materials include 45 steel, 40Cr and so on. 10B21 is also a carbon steel material, but its strength is slightly lower than 45 steel and 40Cr. For Class 8.8 bolts made of 10B21 material, the diameter and length that can be used need to be determined according to specific standards and design requirements.