Manganese bronze contains small additions of manganese, iron, and aluminium, plus lead for lubricity, anti-seizing, and bonding. Like the aluminium bronzes, they combine high strength with excellent corrosion resistance. Manganese bronze bearings can operate at high speeds under heavy loads, but require high shaft hardness and nonabrasive operating conditions.
CHEMICAL COMPOSITION
| Elements | Min (%) | Max (%) |
| Cu | 57.00 | 60.00 |
| Pb | 0.30 | 1.20 |
| Si | – | 1.00 |
| Mn | 1.50 | 2.50 |
| Sn | – | 0.50 |
| Fe | – | 0.50 |
| Al | 1.50 | 2.30 |
| Total Others | – | 0.50 |
| Zn | Remainder |
Mechanical Properties According To SAE J463 C67400 (As Per Temper HO2)
| Range (MM) | From | To | UTS Min (Mpa) | PS Min (Mpa) | ELo Min (%) | Hardness Min (HRB) | Hardness Max (HRB) |
| Round (Dia) | 8 | 75 | 630 | 370 | 8 | 170 | 210 |
| Hex (A/F) | 8 | 70 | 630 | 370 | 8 | 170 | 210 |
| Square | 8 | 60 | 630 | 370 | 8 | 170 | 210 |
| Rectangle (Thickness) | 8 | 50 | 630 | 370 | 8 | 170 | 210 |
| PHYSICAL PROPERTIES |
| Melting Point – Liquidus°F | 1625 |
| Melting Point – Solidus°F | 1590 |
| Density lb/cu in. at 68°F | 0.292 |
| Specific Gravity | 8.08 |
| Electrical Conductivity % IACS at 68°F | 23 |
| Thermal Conductivity Btu/ sq ft/ ft hr/ °F at 68°F | 58 |
| Coefficient of Thermal Expansion 68-57210⁻⁶ per °F (68 – 572°F) | 11 |
| Specific Heat Capacity Btu/ lb /°F at 68°F | 0.09 |
| Modulus of Elasticity in Tension ksi | 16000 |
| Modulus of Rigidity ksi | 6000 |
| FABRICATION PROPERTIES |
| Technique | Suitability |
| Soldering | Fair |
| Brazing | Good |
| Oxyacetylene Welding | Not Recommended |
| Gas Shielded Arc Welding | Fair |
| Coated Metal Arc Welding | Not Recommended |
| Spot Weld | Good |
| Seam Weld | Good |
| Butt Weld | Good |
| Capacity for Being Cold Worked | Poor |
| Capacity for Being Hot Formed | Excellent |
| Forgeability Rating | 100 |
| Machinability Rating | 30 |
TYPICAL USES
- Oil and gas Industries
- Aerospace
- Fastener
- Marine
