| 摘要 |
A method of depositing a bismuth or bismuth alloy overlay 10 on a substrate 11, comprising electroplating the overlay using a plating cycle made-up of a first mode of deposition, followed by a second mode of deposition, wherein one mode is pulsed-current deposition and the other mode is continuous direct current deposition, and optionally repeating cycles to accumulate an intended overlay thickness. Also disclosed is a sliding bearing comprising a backing layer, a bearing metal layer deposited on the backing layer, an optional intermediate layer deposited on the bearing metal layer, and a bismuth or bismuth alloy overlay 10 layer deposited on the bearing metal layer or intermediate layer, characterised in that said overlay comprises a plurality of electrodeposited sub-layers. The plating cycle may comprise sequential application of the DC mode and pulse current mode where the DC mode may follow or precede the pulse mode. The DC current deposition and/or pulsed current may be applied at a constant current level. The overall thickness of the overlay may be from 3-40 µm, where a thickness of 0.1-20 µm may be achieved by one pulsed current plating step or one direct current step in one plating cycle. The overlay 10 thickness deposited in each mode in each cycle may also be different. The bismuth or bismuth alloy may be co deposited with one or more soft particles with a Mohr hardness of ≤5, or one or more hard particles with a Mohr hardness of ≥5. |
