IS 291 GR l
IS 291 Gr I, commonly recognized as naval brass, garners frequent utilization across a diverse array of marine and subsea applications. Esteemed for its exceptional amalgamation of superior strength and robust corrosion resistance, this brass alloy further boasts effective property retention even under cryogenic conditions. Remarkably, IS 291 Gr I exhibits excellent hot formability and underscores a highly commendable level of corrosion resistance.
CHEMICAL COMPOSITION
| Elements | Min (%) | Max (%) |
| Cu | 61.00 | 64.00 |
| Pb | – | 0.20 |
| Sn | 1.00 | 1.50 |
| Fe | – | 0.10 |
| Total | – | 0.20 |
| Zn | Remainder | |
MECHANICAL PROPERTIES ACCORDING TO IS 291 GR I (AS PER TEMPER HB)
| Range (mm) | From | To | UTS Min (MPa) | PS Min | Elongation Min (%) | Hardness Min (HRB) | Hardness Max (HRB) |
| Round (Dia) | 1.5 | 12.5 | 390 | – | 18 | – | – |
| 12.5 | 50 | 380 | – | 18 | – | – | |
| 50 | 75 | 345 | – | 18 | – | – | |
| Hex (A/F) | 3 | 12.5 | 390 | – | 18 | – | – |
| 12.5 | 50 | 380 | – | 18 | – | – | |
| 50 | 65 | 345 | – | 18 | – | – | |
| Square (A/F) | 3 | 12.5 | 390 | – | 18 | – | – |
| 12.5 | 50 | 380 | – | 18 | – | – | |
| 50 | 60 | 345 | – | 18 | – | – | |
| Rectangle (Thickness) | 3 | 12.5 | 390 | – | 18 | – | – |
| 12.5 | 50 | 380 | – | 18 | – | – |
| PHYSICAL PROPERTIES | |
| Melting Point – Liquidus°F | 1650 |
| Melting Points – Solidus 0F | 1630 |
| Density lb/cu in. at 68 0F | 0.304 |
| Specific Gravity | 8.41 |
| Electrical Conductivity % IACS at 68 0F | 26 |
| Thermal conductivity Btu/ Sq ft / ft hr / 0F at 680F | 67 |
| Coefficient of Thermal Expansion 68-57210 -6 Per 0F (68-5720F) | 11.8 |
| Specific Heat capacity Btu/ lb /0F at 680F | 0.09 |
| Modulus of Elasticity in Tension ksi | 15000 |
| Modulus of Rigidity ksi | 5600 |
| FABRICATION PROPERTIES | |
| Technique | Suitability |
| Capacity for being Cold Worked | Fair |
| Hot Worked | Excellent |
| Machinability Rating | 30% |
| Forgeability Rating | 90% |
| Silver Alloy Brazing | Excellent |
| Soft Soldering | Excellent |
| Oxyacetylene Welding | Good |
