SUM12 cutting steel:
Standard: JIS G4804-1999
● Features and Scope:
SP compound is carbon free cutting steel, free cutting steel is available in a maximum amount of phosphorus, cutting resistance than the 15th steel has improved significantly. Mechanical properties of steel have significant anisotropy, the mechanical properties of cold-drawn and cold-drawn steel vertical close on the 15th of steel, often in place of the 15th steel less demanding on the mechanical properties of various parts, such as bolts, nuts, pins, shafts , jackets and other fittings and spark plugs.
● Chemical Composition:
Carbon C: 0.08 ~ 0.16
Si Si: 0.15 ~ 0.35
Mn Mn: 0.70 ~ 1.00
Sulfur S: 0.10 ~ 0.20
P P: 0.08 ~ 0.15
● Mechanical Properties:
Tensile strength σb (MPa) :( hot) 390 to 540; (cold drawn) steel thickness or diameter of 8 to 20 o'clock: 530 to 755;> 20 to 30: 510 - 735;> 30: 490 - 685
Elongation δ5 (%) :( hot rolled) ≥22; (rolled) ≥7.0
Reduction of area ψ (%) :( hot rolled) ≥36
Hardness :( hot) ≤170HB; (cold drawing) 152 ~ 217HB
● Heat treatment and microstructure specifications:
● Delivery status: hot-rolled or cold-drawn delivery, the delivery status should be specified in the contract.