Looser Special Brass 24 (LSM 24) – CuZn34Mn3Al2Fe1-C-GS/GZ/GM DIN EN 1982
Looser Special Brass 24 is a very high strength multi-material alloy based on copper, zinc and aluminium with additions of manganese, iron and nickel (formerly called steel bronze). It is suitable for structural parts that are exposed to high surface pressures and low sliding speeds. It is only suitable for use as a bearing material and for spindle nuts with very good lubrication. Not recommended for dynamic loads, e.g. vibrations. In contrast, Looser Special Brass 24 offers high static strength with good elongation. Can be used at temperatures up to 120°C.
Chemical composition (DIN EN 1982:2017-11)
Element Cu* Zn Mn Al Fe Ni Pb Sn Si Sb P
Min. [%] 55 - 1 1 0,5 - - - - - -
Max. [%] 66 Rest 4 3 2,5 3 0,3 0,3 0,1 0,05 0,03
* inclusive Ni
Mechanical properties (DIN EN 1982:2017-11)
Centrifugal casting-GZ
Yield point Rp0,2 [N/mm2] ≥ 260
Tensile strength Rm [N/mm2] ≥ 620
Brinell hardness [HB] ≥ 150
Elongation at fracture A [%] ≥ 14
Bending fatigue strength* Rbw [N/mm2] ± 170
Modulus of elasticity** E [kN/mm2] ≥ 90
* Guideline value with 108 load cycles and at 20°C / ** 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] 20 Electrical conductivity [m/Wmm2] 7,5
Thermal conductivity [W/mK] 57 Specific gravity [kg/dm3] 8,6
Standards
DIN EN 1982 CuZn34Mn3Al2Fe1-C-GS/GZ/GM DIN 1709 G/GZ/GK-CuZn34Al2 (G-SoMs F60)
VSM 10810 G-CuZn34Al2FeMn
Material designation
DIN EN 1982 DIN 1709
Abbreviated designation Number Casting method Abbreviated designation Number
CuZn34Mn3Al2Fe1-C-GS CC764S-GS GS or G G-CuZn34Al2 2.0596.01
CuZn34Mn3Al2Fe1-C-GM CC764S-GM GM or GK GK-CuZn34Al2 2.0596.02
CuZn34Mn3Al2Fe1-C-GZ CC764S-GZ GZ GZ-CuZn34Al2 2.0596.03
GS = G = Sand casting, GM = GK = Permanent mold casting, GZ = Centrifugal casting
Example uses
Plain bearings with high surface pressures but low sliding speeds (maximum permissible static surface pressure [p] 120 N/mm2). For even higher surface pressures, we recommend Looser Special Brass 27. Slow-running worm wheel rims, spindle nuts, pressure nuts for rolling mills, gear components, valve and control elements, seats and cones.
Machinability
Satisfactory machinability, difficult to weld, not suitable for soldering.
Sliding partners
It is essential to use a hardened and finely ground material as the mating material. Good lubrication is required.
Looser Special Brass 24 – Availability
Centrifuged rings and bushings pre-turned to the rough sizes or contour.
We will be more than pleased to advise you.
Subject to technical modifications; no responsibility is accepted for the accuracy of this information.
Links
Additional information can be found in this Looser Bronzes catalogue or under download.