DIN 17222 Ck67 1.1231 Cold Rolled Steel Strips for Springs

Cold rolled steel strip for springs is distinguished by high dimensional accuracy and good surface quality and, in the cold rolled + hardened + tempered condition (H + A) offers the possibility of achieving high values of hardness, tensile strength and elastic limit.

Ck67 1.1231 Introduce

Ck67 1.1231 steel is an unalloyed medium carbon engineering steel which has 0.65%-0.72% Carbon. Ck67 steel with low hardening capacity designed for less loaded springs, periodically working for oil hardening

Ck67 1.1231 Dimensions and permissible deviations

Thickness: 0.1 to 4mm; Tolerances: +/- 0.008 to 0.11 mm

Width: 10 to 600mm; Tolerances: +/- 0.15 to 0.60mm

Ck67 1.1231 Equivalent Grade

Ck67 1.1231 Chemical composition

Ck67 1.1231 Treatment condition on delivery

Cold rolled + soft annealed : G

Cold rolled + hardened + tempered : H + A

Ck67 1.1231 Mechanical properties in the cold rolled + soft annealed condition G

Ck67 1.1231 Tensile strength in the cold rolled + hardened + tempered condition (H + A)

Ck67 1.1231 Vickers hardness in the cold rolled + hardened + tempered condition (H + A)

Ck67 1.1231 Surface condition

Strip to be supplied in the

1 cold rolled + soft annealed G or

2 cold rolled + soft annealed + cold rolled (G + K) condition

must have a bright, metallically clean surface.

Cold rolled + hardened + tempered (H + A) strip is supplied, as agreed at the time of ordering, with

1 grey-blue (GR),

2 bright (8K),

3 polished (P) or

4 polished and colour-tempered (P & AF) surface.

Ck67 1.1231 Types of heat treatment

Approximate values for heat treatment and minimum hardness values in the hardened condition of cold rolled steel strips for springs

Ck67 1.1231 Acceptance testing and test certificates

EN 10204/3.1 with all relevant data reg. chem. composition, mech. properties and results of testing.