Executive Standard: JIS G4804-1999
● Features and application:
The SP composite carbon free cutting steel, free cutting steel is available in a maximum amount of phosphorus, compared with 15 steel cutting of significant improvement. Mechanical properties of steel significantly anisotropic, the longitudinal mechanical properties of cold-drawn steel and cold-drawn steel close to 15, usually made of steel instead of 15, less demanding on the mechanical properties of various parts such as bolts, nuts, pins, shaft , jackets and other fittings and spark plugs.
● Chemical Composition:
Carbon C: 0.08 ~ 0.16
Si Si: 0.15 ~ 0.35
Manganese Mn: 0.70 ~ 1.00
Sulfur S: 0.10 ~ 0.20
Phosphorus P: 0.08 ~ 0.15
● Mechanical Properties:
Tensile strength σb (MPa): (hot) 390 - 540; (cold drawn) steel thickness or diameter of 8 to 20 hours: 530 ~ 755;> 20 to 30 hours: 510 ~ 735;> 30 hours: 490 ~ 685
Elongation δ5 (%):( hot) ≥ 22; (cold) ≥ 7.0
Reduction of ψ (%):( hot) ≥ 36
Hardness: (hot) ≤ 170HB; (cold drawing) 152 ~ 217HB
● Heat treatment and microstructure specifications:
● Delivery status: the hot-rolled or cold-drawn state of delivery, delivery status should be indicated in the contract.
