carbon-steelISO 898-1
Property Class 4.8
Low or medium carbon steel, general purpose. Common in furniture and light assemblies.
Tensile Rm420 MPa
Yield Rp0.2340 MPa
HardnessHRB 67–95
Nut class4
Mechanical properties
- Property class
- Property Class 4.8
- Defined in
- ISO 898-1
- Tensile strength Rm (min)
- 420 MPa
- Yield strength Rp0.2 (min)
- 340 MPa
- Hardness
- HRB 67–95
- Matching nut class
- 4
- Material
- Carbon Steel
Where this grade is used
Property classes are stamped on the head of bolts and screws above 5 mm diameter. A Property Class 4.8 fastener is specified where the joint needs a proof load of roughly 306 MPa or less. Always match the bolt class with a nut of class 4 or higher so the bolt fails before the thread strips.