Alloy 260， Bar(Round bar, Flat bar)，UNS N03260,E FORU

British Specs:，American Specs: AMS 5890 Bar and Forgings，German Specs:

### **Product Datasheet: Alloy 260 (Cartridge Brass, 70/30) Bar** **UNS Designation:** UNS C26000 **Common Names:** Cartridge Brass, 70/30 Brass #### **Overview** Alloy 260 is a single-phase alpha brass composed primarily of copper and zinc, known commercially as Cartridge Brass. It is the most versatile and widely used brass alloy due to its optimal combination of high ductility, excellent cold-working properties, good strength, and superior machinability. The "70/30" name refers to its typical composition of 70% copper and 30% zinc. Supplied in bar form—including **round bar** and **flat bar**—Alloy 260 is a premier choice for machining, forging, and general fabrication. Round bar is predominantly used for screw-machined components, while flat bar is ideal for brackets, guides, and architectural trim. #### **Key Characteristics** * **Excellent Cold Workability:** Ideal for bending, forming, and stamping operations without annealing. * **High Machinability:** Offers a machinability rating of 100% (Free-Cutting Brass C36000 = 100%), making it highly efficient for high-speed automatic screw machines and CNC machining. * **Good Strength and Hardness:** Provides a solid strength-to-weight ratio, which can be enhanced through cold working. * **Attractive Appearance:** Possesses a warm, gold-like color, suitable for both functional and decorative applications. * **Good Corrosion Resistance:** Resists corrosion in atmospheric, fresh water, and steam services. It is, however, susceptible to dezincification in stagnant or certain aggressive waters. * **Excellent Electrical Conductivity:** Suitable for various electrical components. --- #### **Chemical Composition (Weight % - ASTM B16 Specification)** | Element | Content (%) | | :--- | :--- | | Copper (Cu) | 68.5 - 71.5 | | Zinc (Zn) | Remainder | | Iron (Fe) | ≤ 0.05 | | Lead (Pb) | ≤ 0.07 | | Other Elements (Total) | ≤ 0.15 | *Note: The intentionally low lead content makes Alloy 260 a suitable choice for applications with environmental restrictions or those involving potable water, distinguishing it from free-machining grades like C36000.* --- #### **Physical Properties (Typical)** | Property | Value | | :--- | :--- | | Density | 8.53 g/cm³ (0.308 lb/in³) | | Melting Point (Liquidus) | 955 °C (1750 °F) | | Melting Point (Solidus) | 915 °C (1680 °F) | | Electrical Conductivity | 28% IACS | | Thermal Conductivity | 120 W/m·K | | Coefficient of Thermal Expansion | 20.2 x 10⁻⁶/°C (20-300°C) | | Modulus of Elasticity | 110 GPa (16 x 10⁶ psi) | --- #### **Mechanical Properties (for Bar - Typical by Temper)** The mechanical properties are highly dependent on the temper condition, which is achieved by cold working (drawing or rolling) after annealing. | Condition | Tensile Strength (MPa) | Yield Strength (0.5% Ext) (MPa) | Elongation (% in 2 in) | Hardness (Rockwell B) | | :--- | :--- | :--- | :--- | :--- | | **O60 (Annealed)** | 325 - 410 | 75 - 145 | 55 - 65 | 40 - 60 | | **H02 (1/2 Hard)** | 415 - 485 | 205 - 330 | 25 - 45 | 70 - 85 | | **H04 (Hard)** | 485 - 565 | 395 - 485 | 8 - 20 | 85 - 92 | | **H08 (Spring)** | 520 - 600 | 450 - 520 | 5 - 12 | 90 - 96 | --- #### **International Standards** Alloy 260/C26000 bar is specified in numerous international standards for both rod (round bar) and flat bar. * **ASTM (USA):** * **ASTM B16:** Standard Specification for Free-Cutting Brass Rod, Bar and Shapes for Use in Screw Machines. (Covers Round Bar) * **ASTM B21:** Standard Specification for Naval Brass Rod, Bar, and Shapes. (Specific alloys, but a key bar standard) * **ASTM B249/B249M:** Standard Specification for General Requirements for Wrought Copper and Copper-Alloy Rod, Bar, and Shapes. * **SAE (USA):** * **SAE J461:** Wrought Copper and Copper Alloys. * **EN (European Norm):** * **CW508L (Formerly CW505L):** Material designation. * **EN 12164:** Copper and copper alloys - Rod for free machining purposes. * **EN 12165:** Copper and copper alloys - Wrought and unwrought forging stock. * **EN 1652:** Copper and copper alloys - Plate, sheet, strip and circles for general purposes. (Covers flat bar/rectangular section) * **DIN (Germany):** * **DIN 17660:** CuZn30 (CZ106). * **JIS (Japan):** * **JIS H3250:** C2600 (Rod & Bar). --- #### **Product Applications** **Round Bar:** * **Screw Machine Parts:** Ideal for high-volume production of precision components like fittings, fasteners, and valve parts on automatic screw machines. * **Electrical Components:** Terminals, connectors, and switch parts. * **Shafts and Pins:** For low-stress, corrosion-resistant applications. * **Decorative Turnings:** For furniture, marine, and architectural hardware. **Flat Bar:** * **Structural Components:** Used for brackets, supports, and braces in marine and architectural applications. * **Architectural Trim:** Door handles, kick plates, nameplates, and decorative moldings. * **Machined Parts:** Bases, plates, and guides that require a flat profile for fabrication. * **General Fabrication:** Custom parts for machinery, exhibits, and consumer goods. --- #### **Disclaimer** This information is presented in good faith for informational purposes only. The properties and performance of Alloy 260 bar can be influenced by manufacturing processes, specific temper, size, and service environments. For critical applications, it is essential to consult with the material supplier and refer to the complete, official standard specifications.

Packing of Standard Packing: Typical bulk packaging includes palletized plastic 5 gallon/25 kg. pails, fiber and steel drums to 1 ton super sacks in full container (FCL) or truck load (T/L) quantities. Research and sample quantities and hygroscopic, oxidizing or other air sensitive materials may be packaged under argon or vacuum. Solutions are packaged in polypropylene, plastic or glass jars up to palletized 2809 gallon liquid totes Special package is available on request.