Alloy 25 (UNS C17200) is the most commonly specified beryllium copper and is available in several wrought forms. In its age-hardened condition, Alloy 25 attains the highest strength and hardness of any commercial copper base alloy. The ultimate tensile strength can exceed 200 ksi, while the hardness approaches Rockwell C45. Also, in the fully aged condition, the electrical conductivity is a minimum of 22% IACS (International Annealed Copper Standard). Alloy 25 also exhibits exceptional resistance to stress relaxation at elevated temperatures.

12' Random Lengths
Condition H (Hardened)
CDA 172 ASTM B196
AMS 4650 UNS 17200
Nominal Composition:
Copper: 98.1% Beryllium: 1.9%
Also available in condition A (annealed).
Unit of Measure



N/A Beryllium Copper


N/A Round Rod


N/A A (Annealed) H (Hardened)


N/A Alloy 25


N/A 15/32 inches


N/A 0.4688 inches11.90752 mm


N/A 0.6173 lbs/ft0.91866586 kg/m

Weight per 12' Length

N/A 7.407 lbs3.3590745 kg

Nominal Composition

N/A 0.20% Min. Cobalt + Nickel 0.6% Max. Cobalt + Nickel + Iron 1.9% Beryllium 98.1% Copper

ASTM Specification

N/A AMS 4650 ASTM B196 CDA 172 UNS 17200

Random Lengths

N/A 12 ft


N/A AMS 4650 AMS 4651 ASTM B196 ASTM B251 ASTM B643 RWMA Class 4 SAE J461 SAE J463

Typical Physical Properties


N/A 0.302 lbs/in³

Elastic Modulus

N/A 19 x 106 psi

Coefficient of Thermal Expansion (70ºF to 400ºF)

N/A 9.7 x 104 in/in/ºF

Thermal Conductivity

N/A 60 Btu/(ºF)

Melting Temperature Range

N/A 1600 to 1800 ºF