To improve the corrosion protection properties it is possible to combine the hard chrome layer with a second layer underneath the chrome. In this case a separation of the functions of the layers is made, the hard chrome layer functions as a wear and tear protection, the base layer functions as a corrosion barrier. Usually the base layer is made of a galvanized Nickel. Over and above we can offer to combine the hard chrome layer with a thermic sprayed NiCr base layer or with a P.T.A. welded layer. Also for the repair of piston rods this is an interesting option, because with the base layer the original diameter can be rebuilt.

Technical facts:

• Mechanical surface qualities like a conventional hard chrome layer
• Layer thickness of the base layer 200 µm, of the top layer 50 µm
• Hardness of the chrome layer 800 HV to 950 HV
• Surface treatment by Superfinishing Ra 0.05 – 0.09 µ m

Properties:
Improved corrosion resistance compared with hard chrome

Field of application:
Hydraulic cylinder requiring increased corrosion protection, in the general machine engineering, hydromechanical engineering, construction machines, printing industry, chemical industry etc.