Looser Lead Bronze 85 (LBB 85) – CuSn5Pb20-C-GS/GC/GZ DIN EN 1982
In the liquid state, lead is practically insoluble in copper. For this reason, highly leaded bronzes such as Looser Lead Bronze 85 are difficult to produce. Due to the rapid cooling rate in the continuous casting process, however, Looser Leaded Bronze 85 produced in this way has a remarkably fine lead distribution in copper, even with substantial cross sections.
Looser Lead Bronze 85 has optimum sliding and emergency running properties and is therefore also suitable for bushings lubricated only in water or temporary dry-running bushings and for bearings with low surface pressures and relatively high speeds. With good lubrication, maximum surface pressures [p] of 20 to 30 N/mm2 are permissible.
Due to the plasticity of the material, Looser Lead Bronze 85 is insensitive to misalignment and edge pressures. It offers good embeddability for foreign bodies.
Thanks to its good corrosion resistance against sulphuric acid, it is an ideal material for fittings and apparatus used in the chemical industry.
Chemical composition (DIN EN 1982:2017-11)
Element Cu* Pb Sn Ni Zn Sb Fe Mn S P Al Si
Min. [%] 70 18 4 0,5 - - - - - - -
Max. [%] 78 23 6 2,5 2 0,75 0,25 0,2 0,1 0,1 0,01 0,01
* inclusive Ni
Mechanical properties (DIN EN 1982:2017-11)
Continuous casting-GC
Yield point Rp0,2 [N/mm2] ≥ 90
Tensile strength Rm [N/mm2] ≥ 180
Brinell hardness [HB] ≥ 50
Elongation at fracture A [%] ≥ 7
Modulus of elasticity* E [kN/mm2] ≥ 74
* Guideline value
The sample bar is removed from the casting in the case of centrifugal castings and continuous castings. The sample position – e.g. lengthwise or crosswise sample – must be agreed between orderer and manufacturer: the values specified in the table apply only to wall thicknesses up to 50 mm for the blank casting. In the case of wall thicknesses over 50 mm, with the wall thickness of the blank casting being the decisive factor, it must be anticipated that the strength and hardness values are lower. This applies in particular to the yield point.
It must not be expected that the strength and hardness values are uniformly high at all points of the casting. In general, the values in the outer layers will be higher than in the core zone.
Physical properties (Guideline values)
Coefficient of thermal expansion [10-6/K] 19,3 Electrical conductivity [m/Wmm2] 8,5
Thermal conductivity [W/mK] 71 Specific gravity [kg/dm3] 9,3
Standards
DIN EN 1982 CuSn7Pb15-C-GS/GC/GZ VSM 10810 G-CuPb15Sn8 (G-PbBz15)
DIN 1716 G/GC/GZ-CuPb15Sn (G-SnPbBz15) ASTM Alloy C 93900
Material designation
DIN EN 1982 DIN 1716
Abbreviated designation Number Casting method Abbreviated designation Number
CuSn5Pb20-C-GS CC497K-GS GS or G G-CuPb20Sn 2.1188.01
CuSn5Pb20-C-GZ CC497K-GZ GZ - -
CuSn5Pb20-C-GC CC497K-GC GC - -
GS = G = Sand casting; GZ = Centrifugal casting; GC = Continuous casting
Example uses
Bearings for water pumps and fans, thrust and sealing rings for compressors and underwater pumps. Bearings for cold and foil rolling mills, bearings with substantial, unavoidable edge pressures.
Machinability
Looser Lead Bronze 85 is easy to machine. It is suitable for soft and hard soldering but not for welding.
Sliding partners
Both hardened and unhardened shafts can be used. The bearing clearance can be kept relatively tight because a good runin is guaranteed.
Looser Lead Bronze 85 – Availability
- Numerous sizes of tubular and round bars are available from stock or at short notice.
- Ready-to-install parts in accordance with customer drawing.
We will be more than pleased to advise you.
Subject to technical modifications; no responsibility is accepted for the accuracy of this information.