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What are babbitt metals and how are they used in machine bearings?

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A labeled periodic table entry for antimony shows its symbol Sb, atomic number 51, atomic weight 121.76, electron configuration, and name. It is a solid, weakly acidic other metal with a rhombohedral crystal structure at room temperature. — antimony Properties of antimony.

Babbitt metals are a group of tin- or lead-based alloys used to provide low-friction linings for machine bearings, such as those found in axles and crankshafts. Invented by Isaac Babbitt in 1839, these alloys typically incorporate antimony and copper to achieve specific mechanical properties.12

Composition and Function

Babbitt metals consist of hard metal particles embedded within a softer matrix of tin or lead. This unique structure serves two primary purposes in machine bearings:1
* Load Bearing: The material is strong enough to support relatively high speeds and heavy loads.1
* Protection: The soft matrix allows the bearing to embed dirt or other foreign particles, preventing them from damaging the spinning shaft. Additionally, if lubrication fails, the material is designed to prevent the bearing from seizing up.1

While tin-based babbitts can withstand higher temperatures than lead-based versions, they are generally not suitable for the extreme demands of high-performance internal-combustion engines, which now typically utilize copper and aluminum alloy linings.1