65Mn Spring Steel Bar

65Mn Spring Steel Bar

65Mn steel is commonly used as spring steel, and the final heat treatment is quenched and tempered.

Chinese name:65Mn steel

sort:industry

Domain:unit

peculiarity:Low cold deformation plasticity, poor weldability

65mn steel strip

Strength, hardness, elasticity and hardenability are much better than ordinary steel. It has overheating sensitivity and tempering brittleness tendency, and water quenching has cracking tendency. The machinability of annealed state is reasonable, the cold deformation plasticity is low, and the weldability is poor. The surface decarburization tendency is smaller than that of silicon steel.

Chemical composition

Carbon C :0.62~0.70

Silicon Si:0.17~0.37

Manganese Mn:0.90~1.20

Sulfur S :≤0.035

P :≤0.035

Chromium Cr:≤0.25

Nickel Ni:≤0.30

Mechanical property

Tensile strength σb (MPa):≥980(100)

Yield strength σs (MPa):≥784(80)

Elongation δ10 (%):≥8

Section shrinkage ratio ψ (%):≥30

Hardness: hot rolling,≤302HB;

Cold drawing + heat treatment, ≤321HB

use

Used as a small size of various flat, round spring, cushion spring, spring spring, can also make spring ring, valve spring, clutch spring, brake spring and cold drawn wire cold coil spring.

Heat treatment specification

● Heat treatment specifications and metallographic structure:

Heat treatment specification: quench 830℃±20℃, oil cold;

Temper 540 ° C ±50 ° C (for special needs,±30 ° C).

Metallographic structure: troostite.

● Delivery status: Hot rolled steel is delivered in heat treatment or no heat treatment state, cold drawn steel is delivered in heat treatment state.

● Supply specifications:

Disk circle :Φ5.5~16mm

Rolled material :Φ120~150mm

Forging material :Φ160~450mm