HEAT TREATMENT SPECIFICATION:
Tensile strength σb (MPa)≥715,
Yeild strength  σs (MPa)≥420,
englongation δ5 (%)≥9
Reduction area  ψ (%)≥30,
Hardness HBS ≤269；

MECHANICAL PROPERTIES:
DELIVERY CONDITION :
normalized ,annealed, black surface ,rough machined or quenched & tempered , should be indicated in contract .
DIMENSION : mm
length : forged bar free length 4-5.8M,rolled bar 5.8M. for customers special requirment, the bar length can do 20 meters long.
APPLIED RANGE:
Suitable to make round ,square spiral spring which section not big, strength requirement not high. Such as flat plate spring
 and round spiral spring
used in vehicle tractor or train to bear vibratory .

REMARK：

Above listed parameters and sepcification only for reference . Specific parameters according to standard. Requirments beyond standard will be negotiate by both sides .
Delivery state:annealed, spheroidal annealed, quenched & tempered ,bright bar, cold-drawn, etc.
Listed specifications are only typical grades; products of required specifications can be developed/produced per international, Chinese or industry standards, or based
on agreements with customers.