Beryllium Copper Alloy 25 (UNS C17200/CDA 172)

Technical Data Sheet

Chemical Composition Limits
Weight % Cu Al Be Co
AMS 4533
CDA 172
Rem 0.20 1.8-2.0 0.2 min

CDA 172 Beryllium Copper is commonly used due to it's high strength and hardness compared to other commercial copper alloys. CDA 172 strength and hardness is similar to that of steel. To achieve it's high strengths whilst still maintaining acceptable levels of toughness for many industrial applications CDA 172 is age hardened. Toughness, fatigue strength, corrosion resistance etc can be modified and controlled by either underaging or overaging during the precipitation hardening process of the alloy.

Typical Mechanical Properties

Material Condition Size Tensile strength ksi Yield Strength ksi Elongation 2" % Hardness
CDA 172 Round Bar Sol + Precipitation heat treated ( TF00 formerly AT)   165 140 4 36-45 HRC
CDA 172 Round Bar Sol Treated, Cold Worked + Precipitation Heat Treated (TH04, formerly HT) < 0.375" 182 157 3 37-45
CDA 172 Round Bar Sol Treated, Cold Worked + Precipitation Heat Treated (TH04, formerly HT) 0.375" - 1.00" 180 154 3 37-45
CDA 172 Round Bar Sol Treated, Cold Worked + Precipitation Heat Treated (TH04, formerly HT) 1.00" - 2.00" 177 150 3 37-45

Physical Properties
Density - 0.298 lb/in3 at 68 F
Coefficient of Thermal Expansion - 9.9 ·10-6 per oF (68-572 F)
Thermal Conductivity - 62 - 70 Btu · ft/(hr · ft2·oF)at 68 F
Relative Magnetic Permeability (u) - 1.003
Modulus of Elasticity in Tension - 18500 ksi
Machinability Rating - 0%

Typical Uses of CDA 172 (AMS 4533, AMS 4534, AMS 4535, AMS 4650, AMS 4651)
Oil & Gas - Instrument Housings, Flex Shafts, MWD & LWD Components, Bearings, Bushings, Valve Components, Pump Shafts

Aerospace - Landing Gear Bushings, Aircraft Components, Cryogenics

Automotive - RWMA Tooling, Plastic Molds, Electronic Components

Electrical - Contact Bridges, Clips, Spring Connectors, Current Carrying Navigational Instruments, Relay Parts, Electrical Switch and Relay Blades, Connectors, Switch Parts, Fuse Clips

Fasteners - Bolts, Screws, Roll Pins, Retaining Rings, Lock Washers,Belleville Washers, Fasteners, Washers

Other Industrial - Flexible Metal Hose, Non Sparking Safety Tools, Shafts, Pump Parts, Rolling Mill Parts, Bearings, Bushings, Valve Seats, Valve Stems, Diaphragms, Housings for Instruments, Wear Plates onHeavy Equipment, Bourdon Tubes, Bellows, Springs, WeldingEquipment, Spline Shafts, Valves, Pumps, Springs,Electrochemical

Ordinance - Firing Pins

CDA 172 is available in Sheet, Plate, Bar, Strip, Pipe, Rod, Forgings, Extrusions, Tube, Wire. CDA 172 Foil (Shim) is available in various thicknesses. View stock list for further information. Foil Stock List. For all other stock availability contact Sales.


Bar AMS 4650, AMS 4651, AMS 4533, ASTM B194, ASTM B196, MIL C 21657, SAE J463, SAE J461
Extrusions ASTM B570
Forgings AMS 4650, ASTM B570
Plate ASTM B194
Rod AMS 4650, AMS 4534, AMS 4651, AMS 4533, ASTM B196, MIL C 21657, SAE J463, SAE J461
Rod, Forging AMS 4650
Sheet ASTM B 194
Strip ASTM B 194, SAE J463, SAE J461
Tube Seamless AMS 4535, ASTM B643
Wire AMS 4725, ASTM B197, SAE J463, J461
Other UNS C17200

Every effort is made to ensure that technical specifications are accurate. However, technical specifications included herein should be used as a guideline only. All specifications are subject to change without notice.