INFORMATION:

Induction-hardened Cromax IH 482 is based on a medium carbon, micro-alloyed steel, which is characterised by high strength in the as-rolled condition, i.e. without heat treatment. The 482 base steel is a cost-effective alternative to traditional low-alloy, quenched and tempered grades with, in the context of piston-rod applications, equivalent properties.

The analysis of the base steel in Cromax IH 482 is well adapted to induction hardening and a high and uniform hardness is achieved throughout the case irrespective of diameter. In consequence, the resistance to even high-energy external impact is excellent.

SPECIFICATIONS:

The thickness of the chrome layer is minimum 20 μm

The surface roughness (Ra) is always less than 0.2 µm and normally in the range 0.05-0.15 µm. Rt (ISO) is always less than 2.0 µm and normally in the range 0.5-1.5 µm

The chrome layer hardness is 850 HV0.1min. The surface hardness in the induction-hardened zone immediately beneath the chrome layer is 55 HRC min. The depth of hardening, which is defined as the distance from the steel/chrome interface at which the hardness has dropped to 400 HV5, is dependent on diameter as tabulated below:

(Ø) ≤28 mm

Hardening depth (mm): 1.0 – 1.5

(Ø) >28 – 40 mm

Hardening depth (mm): 1.3 – 1.7

(Ø) >40 mm

Hardening depth (mm): 1.7 – 2.3

Other hardening depths can be supplied by special arrangement

The maximum deviation is 0.2 mm/1.0 m

The out of roundness is maximized at 50% of the diameter tolerance interval

ISO f7 is standard. Other tolerances can be supplied upon request (narrowest range is ISO level 7)

TYPICAL MECHANICAL PROPERTIES:

Tensile strength (Rm): 850- 1000 MPa

Yield strength(Re): 580 MPa

Elongation (As): 14%

Hardness (HBW): 250 – 300

Resilience (-20°C): No guarantee given, but normally 15 – 30 J

CORRESPONDING STANDARDS:

Below is the closest equivalent standard for the steel in Cromax IH 482. In most cases, the correspondence is only approximate.

CROMAX 482

EN 38MnVS6

DIN 38MnSiVS5

AFNOR 30MV6

SAE/ASTM 1045V

 
 
 
Ovako Cromax is the major manufacturer in Europe of hard-chrome plated products in the form of bar and tube.