C38500 Free-Cutting Brass (CuZn39Pb3)
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MA38B is the European reference standard for free-cutting brass with machinability rating of 100, moderate strength, and good resistance to corrosion. The alloy is used in the widest range of applications where excellent machining performance is the key selection criteria, including all types of special machined or micro-machined components with or without electrical requirement.
Mechanical Properties
Round Rod
| TEMPER NAME | TEMPER CODE | TENSILE STRENGTH | YIELD STRENGTH | ELONGATION | MILL LIMITS |
| min, ksi (MPa) | min, ksi (MPa) @ 0.2% |
min, % | |||
| soft anneal | R360 | 52 (360) | 46 (320) max | 15 | .02363 - .3150" (6 - 8mm) |
| half-hard | R430 | 62 (430) | 32 (220) | 7 | 0.0787 - 0.3150" (2 - 8 mm) |
| hard | R500 | 73 (500) | 51 (350) | 4 |
Round Wire
| TEMPER NAME | TEMPER CODE | TENSILE STRENGTH | YIELD STRENGTH | ELONGATION | MILL LIMITS |
| min, ksi (MPa) | min, ksi (MPa) @ 0.2% |
min, % | |||
| soft anneal | R360 | 52 (360) | 46 (320) max | 15 | .02363 - .3150" (6 - 8mm) |
| half-hard | R430 | 62 (430) | 32 (220) | 4 | 0.0197 - 0.3150" (0.5 - 8 mm) |
| hard | R500 | 73 (500) | 51 (350) | 4 |
Physical Properties
| Melting Point (Liquidus) | 1630°F | 890°C |
| Melting Point (Solidus) | 1610°F | 875°C |
| Annealing Range (min - max) | 800 - 1100 °F | 427 - 593 °C |
| Density | 0.306 lb/cu in | 8.40 gm/cu cm |
| Electrical Resistivity (Annealed) | 43.0 Ω·cir-mil/ft @ 68 °F | 6.17 µΩ·cm @ 20 °C |
| Electrical Conductivity (Annealed) | 28% IACS @ 68°F | 0.162 MS/cm @ 20°C |
| Thermal Conductivity | 71 Btu/sq ft/ft·hr/°F @ 68 °F | 123 W/m·K @ 20 °C |
| Coefficient of Thermal Expansion | 0.0000116°F (68-572°F) | 0.0000210°C (20-300°C) |
| Modulus of Elasticity (Tension) | 14,000 ksi | 96,500 MPa |
| Modulus of Rigidity | 5,300 ksi | 36,500 MPa |
For a full size version of product specifications, including chemical composition in both US and Metric units, please download the PDF.