Slide Bearing Layers

Layers for Sliding Contact Bearing

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According to the number of the main functional bearing layers the bearings may be mono-metal (solid), bi-metal, tri-metal or multi-layer. Most of engine bearings are either bi-metal or tri-metal.
Typical bearings layers and structures are presented in below:

• Steel back supports bearing structure, provides its rigidity and press fit under severe conditions of increased temperature and cycling loads.

• Intermediate layer (lining)is a layer located between the steel back and the overlay.

• Nickel diffusion barrier (nickel dam)is deposited between the intermediate layer and the overlay in order to prevent a migration of tin from the overlay into the intermediate material (copper).

• Bonding layer is used for good adhesion between the steel back and aluminum-tin alloy.

• Non-plated bearing material is referred to mono-metal (solid) and bi-metal bearings. No overlays are deposited on the surface of the material.

• Tin flash is a very thin (max. 0.00004”/1µm) layer of tin applied to the overall bearing surface.