8737 MOD

8737 MOD, also known as IS 8737 Modified Forging Brass, is a leaded forging brass alloy with manganese added as a strengthening agent. The lead content improves machinability, making it suitable for forging components where machining is required. This alloy is commonly used in manufacturing LPG valves and other forged parts demanding strength, machinability, and corrosion resistance.

Chemical Composition

• Copper (Cu): 56.50 – 60.00%

• Lead (Pb): 1.00 – 2.00%

• Iron (Fe): Up to 0.30%

• Manganese (Mn): 0.50% (minimum)

• Total others (excluding Fe): Up to 0.75%

• Zinc (Zn): Remainder

Mechanical Properties

• Ultimate Tensile Strength (UTS): 392 MPa (minimum)

• Elongation: Minimum 18%

• Hardness: Varies with part form

Physical Properties

• Density: 8.40 g/cm³

• Coefficient of Thermal Expansion (CTE), linear: 26.0 µm/m·°C (14.4 µin/in·°F)

• Specific Heat Capacity: 0.380 J/g·°C (0.0908 BTU/lb·°F)

• Thermal Conductivity: 113 W/m·K (784 BTU-in/hr-ft²-°F)

• Melting Point: Solidus 880°C, Liquidus 900°C (1620–1650°F)

Fabrication Properties

• Machinability: About 80% relative to IS 319 Grade I

• Poor cold workability

• Excellent hot workability (hot forgeability rating 100)

Applications

• Forged components, especially LPG valves

• Industrial hardware requiring machinability and strength

• Mechanical and plumbing fittings