Overview
ISO 4383:2012 - Plain bearings: Multilayer materials for thin-walled plain bearings specifies material requirements for multilayer strip materials used to manufacture thin-walled plain bearings (half bearings, bushes, thrust washers). Published as the fourth edition (2012), it covers the multilayer construction: a steel backing, a bearing layer (cast, sintered, roll-bonded) and optional overlay (electroplated, sputtered or polymer). The standard defines chemical composition limits, material selection guidance and designation rules for multilayer plain bearing materials.
Key topics and requirements
- Scope and measurement: Chemical compositions refer to the original unprocessed material and should be measured on representative samples. Test results on finished bearings may differ due to manufacturing effects and are not directly comparable to the standard’s data.
- Chemical composition: Limits for tin-, copper-, and aluminium-based bearing alloys and for sintered bronze/polymer combinations are specified (see Tables 1–4 in the standard).
- Steel backings: Backing steel composition is to be agreed between manufacturer and purchaser; typically low-carbon steel. Backings must conform to ISO 6280.
- Bearing layers: Acceptable bearing metals include tin alloys, copper–lead–tin alloys (e.g., CuPb24Sn), aluminium-based alloys (e.g., AlSn20Cu), and sintered bronze with polymer running surfaces.
- Overlays: Electroplated overlays (e.g., PbSn10Cu2, PbIn7), sputtered overlays (e.g., AlSn20Cu) and polymer overlays are covered; overlay thickness and interlayers are subject to supplier–purchaser agreement.
- Guidance and design: Annex A provides hardness guidance for bearing strips and recommended minimum hardnesses for mating shafts (application-oriented guidance for high-speed engines and other conditions).
- Environmental note: The standard acknowledges that environmental concerns may restrict use of some materials (for example lead) in future applications.
Applications and who uses it
ISO 4383 is intended for:
- Bearing manufacturers producing thin-walled plain bearings (main/connecting rod bearings, bushes, thrust washers)
- OEMs and component designers specifying multilayer bearing materials
- Material suppliers and metallurgists controlling alloy composition and strip production
- Quality, procurement and testing laboratories applying material acceptance criteria
Practical uses include specification of bearing strip materials for automotive engines, rotating and oscillating shafts, high-speed machinery and any application requiring thin-walled plain bearings with controlled bearing-layer chemistry and overlays.
Related standards
- ISO 4381 - Tin casting alloys for multilayer plain bearings
- ISO 4382-1 - Cast copper alloys for plain bearings
- ISO 6280 - Requirements on backings for multilayer bearings
- ISO 6691 - Thermoplastic polymers for plain bearings
- ISO 4384-1 - Hardness testing of multilayer bearing materials
Keywords: ISO 4383, plain bearings, multilayer materials, thin-walled bearings, bearing alloys, overlays, steel backing, bearing layer, sintered bronze, bearing material specification.