INFORMATION:

Cromax 280X is based on a low carbon, microalloyed steel combining high strength with excellent machinability and weldability. For Ø ≤ 90 mm, yield and tensile strength are 20% higher than is normal for hard-chrome bars based on low-carbon weldable steel. This improvement is achieved without detriment to machinability or weldability.

In comparison with standard products based on grade 20MnV6, the superior properties profile of Cromax 280X offers a number of potential advantages in the design and manufacture of fluid-power cylinders, not the least of which is the possibility to downsize piston rods without loss of load-bearing capacity, thereby reducing not only weight but also cost.

SPECIFICATIONS:

For Ø≥20 mm, the chrome layer thickness is 20 µm min. For smaller sizes, the minimum thickness is 15 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

For Ø<30 mm, the maximum deviation is 0.1 mm/0.5 m. The maximum deviation for larger diameters is 0.1 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:

(Ø) <20 mm

Tensile strength (Rm): 650 – 800 MPa

Yield strength(Re): 520 MPa

Elongation (As): 12%

Hardness (HBW): 200 – 240

Resilience (-20°C): No guarantee

(Ø) 20-90 mm

Tensile strength (Rm): 650 – 800 MPa

Yield strength(Re): 520 MPa

Elongation (As): 19%

Hardness (HBW): 200 – 240

Resilience (-20°C): 27 J

(Ø) >90 mm

Tensile strength (Rm): 550- 700 MPa

Yield strength(Re): 440 MPa

Elongation (As): 19%

Hardness (HBW): 180 – 230

Resilience (-20°C): No guarantee

CORRESPONDING STANDARDS:

Below is the closest equivalent standard for the steel in Cromax 280X.

CROMAX 280X

EN 20MnV6

DIN 20MnV6

BS 55M

AFNOR E420

ASTM A572

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