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Principles of Energy Conversion
Published in Hamid A. Toliyat, Gerald B. Kliman, Handbook of Electric Motors, 2018
Hamid A. Toliyat, Gerald B. Kliman
Babbitt metal has very desirable frictional characteristics and bearing-metal characteristics. It has low surface hardness, in the range 10 to 15 Brinell at 100∘C, and the hardness decreases rapidly at high temperatures. The modulus of elasticity of lead-based babbitt is approximately 2×106 pounds/ inch 2 and of tin-based babbitt is approximately 6×106 pounds/inch2. This permits good conformability of the bearing to the journal and the journals do not usually need to be hardened beyond the degree inherently present in the shaft steel.
Basic Materials Engineering
Published in David A. Hansen, Robert B. Puyear, Materials Selection for Hydrocarbon and Chemical Plants, 2017
David A. Hansen, Robert B. Puyear
Carbon is also used in mechanical seals. To obtain greater wear life, the contact surface of carbon components can be converted to silicon carbide by high-temperature exposure to silicon monoxide. Alternatively, they may be impregnated with a phenolic resin or metals such as antimony or Babbitt. (Babbitt is the name of a family of tin-based bearing alloys.)
Friction, Lubrication, and Wear
Published in John B. Heywood, Eran Sher, The Two-Stroke Cycle Engine, 2017
Two approaches are in common use: In the first, the surface is coated with a thin film with superior friction and wear properties, which protects the substrate material from excessive wear. In the second approach, the surface is coated with a solid lubricant that forms a sacrificial film designed to wear continuously during use. It protects the substrate by producing wear debris that provides lubrication in addition to the liquid film. This method has been successfully applied to bearing technology (babbit, an alloy used for lining bearings, is a sacrificial tribological film) and to pistons in gasoline engines (lead or tin is often used to prevent scuffing wear during engine break-in).
A New Design Chart Method of Journal Bearings Based on a Simplified Thermohydrodynamic Lubrication Theory
Published in Tribology Transactions, 2020
Babbitt-lined bearing surfaces are widely used in oil film bearings for high-speed rotating machinery. The tensile strength of babbitt metal decreases with temperature, eventually resulting in bearing surface damage called melting and wiping around the minimum oil film thickness position where the maximum shearing force and maximum bearing temperature are normally found. Consequently, high-speed journal bearings need be designed so that in operation never exceeds a prescribed upper limit.