DIN 17222 Ck60 1.1221 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.

Ck60 1.1221 Introduce

Ck60 1.1221 Carbon Steel is a high-carbon steel of low hardenability; it may be used in the as-rolled, annealed, normalized or liquid-quenched-and-tempered condition, depending on the desired properties. It is normally hardened by austenitizing and quenching in oil; however, it may be quenched in water if precautions are taken to prevent cracking. Its many uses include springs.

Ck60 1.1221 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

Ck60 1.1221 Equivalent Grade

Ck60 1.1221 Chemical composition

Ck60 1.1221 Treatment condition on delivery

Cold rolled + soft annealed : G

Cold rolled + hardened + tempered : H + A

Ck60 1.1221 Mechanical properties in the cold rolled + soft annealed condition G

Ck60 1.1221 Tensile strength in the cold rolled + hardened + tempered condition (H + A)

Ck60 1.1221 Vickers hardness in the cold rolled + hardened + tempered condition (H + A)

Ck60 1.1221 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.

Ck60 1.1221 Types of heat treatment

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

Ck60 1.1221 Acceptance testing and test certificates

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