Global Certificate
ISO 9001 : 2015
| Alloy Name | |
| AMW31 | CuSn4 |
| IS/ISO | CuSn4 |
| DIN CEN/TS 13388 | CW450K |
| UNS | C51100 |
| JIS | C51100 |
| This alloy is as per ROHS specification | |
KEI Produces highest quality bronze strips in a thickness range from 0.1 mm to 3 mm in a slit width of 10 mm to 400 mm for Connectors , Electrical contacts , Spring elements & switches.
CuSn4 provides an excellent combination of strength, excellent formability and hardness. It has a good electrical conductivity and corrosion resistance. Soldering and brazing properties are excellent. We offer exceptionally narrow tolerances with regard to chemical composition, dimensional precision and mechanical properties. Special characteristics such as superfine particle size or thermal- mechanical stress relieving improve mechanical properties and provide increased strength and greater malleability.
| Chemical Composition | Weight percentage |
| P | 0.03 - 0.35 % |
| Sn | 3.5 - 4.5 % |
| Pb | 0.02 Max % |
| Zn | 0.30 Max % |
| Fe | 0.10 Max % |
| Cu | Remainder % |
| Main Applications |
| Electrical : Contact Springs,Relais Springs,Terminals,Switch Parts Fuse Clips, Electronic connectors |
| Fasteners : Lock Washers, Fasteners |
| Industrial : Textile Machinery, perforated Sheets,Springs,Sleeve Bushing,Clutch Disks. |
| General : Stamped parts,Connectors,Contact Springs, spring Elements, Ultra high strength spring elements, Fixed contacts. |
| Physical Properties Typical values in annealed temper at 20 °C | ||
| Density | 8.85 | g/cm3 |
| Thermal expansion coefficient -191 .. 16 | 17.8 | 10-6/K |
| Specific heat capacity - 0 .. 300°C | 18.1 | 10-6/K |
| Thermal conductivity | 0.377 | J/(g•K) |
| Electrical conductivity (1 MS/m = 1 m/(O mm²) | 100 | W/(m•K) |
| Electrical conductivity (IACS) | 11 | MS/m % |
| Thermal coefficient of electrical resistance (0 .. 200 C) | 0.10 | 10-3/K |
| Modulus of elasticity ( 1 GPa = 1 kN/mm²) cold formed | 110 | GPA |
| Mechanical Properties (EN 1652) | ||||
| Temper | Tensile Strength Rm MPa(N/mm2) |
Yield Strength Rp0.2 MPa(N/mm2) |
Elongation A50mm % |
Hardness HV |
| O (SOFT) | 295 Min | 190 | 40 Min | 80 Max |
| HA (Quater Hard) | 340 Min | 320 | 30 Min | 100 Min |
| HB (Half Hard) | 460 Min | 440 | 8 Min | 150 Min |
| HD (Hard) | 540 Min | 480 | 4 Min | 180 Min |
| HE (Extra Hard) | 620 Min | 560 | 2 Min | 190 Min |
| HS (Spring Hard) | 650 Min | 620 | 200 Min | |