ThePipingMart Blog Grades UNS C17200 Beryllium Copper (Alloy 172) – Composition, Properties, & Uses

UNS C17200 Beryllium Copper (Alloy 172) – Composition, Properties, & Uses

Beryllium Copper 172-

What is Beryllium Copper 172?

Beryllium copper, or alloy 172, is a unique metal alloy with many useful properties. This alloy contains a combination of copper, beryllium, and other elements that lend it the ability to withstand extreme temperatures and corrosive environments. It is also used in applications requiring thermal conductivity, strength, and electrical conductivity. In this blog post, we’ll explore the physical, chemical, mechanical, and corrosion resistance properties of beryllium copper 172 and its heat treatment and heat resistance capabilities.

What Forms is Beryllium Copper 172 Available at Piping Mart?

  • Bar
  • Bolt
  • Pipe
  • Screw
  • Tubing
  • Valves
  • Washers
  • Flanges
  • Fasteners

C17200 Beryllium Copper Composition

The alloy contains approximately 2% beryllium, giving it superior corrosion resistance compared to other copper alloys. This makes it an ideal choice for applications where exposure to harsh chemicals may be expected. Additionally, beryllium copper 172 is resistant to hydrogen embrittlement, which can cause failure in other materials when exposed to hydrogen at high pressures and temperatures.

Chemistry Information
Element Percentage
Be 1.9
Co 0.2
Cu 97.9

Alloy 172 Physical Properties

Beryllium copper 172 has an impressive range of physical properties. It has a high elastic limit, excellent wear resistance, and toughness. Its high tensile strength makes it ideal for applications requiring superior performance under harsh conditions, such as oil rigs and drilling platforms. Additionally, UNS C17200 low thermal expansion makes it suitable for use in aerospace applications such as aircraft engines.

Physical Properties 172
Density 0.298 lb/in3
Ultimate Tensile Strength 84.8-115 ksi
Yield Tensile Strength 74.7-105 ksi
Fatigue Strength 37 ksi
Shear Strength 64 ksi
Shear Modulus 6,500 ksi
Hardness Rockwell | Brinell B88-102 | 176-253
Elongation at Break Percentage 10-20%
Modulus of Elasticity 18,100-18,900 ksi
Poisson’s Ratio 0.30
Machinability Percentage 20%
Melting Point 1,590-1,800 °F
Specific Heat 1.0 x 10^-1 BTU/lb-°F
Thermal Conductivity 729-902 BTU-in/hr-ft^2-°F
Electrical Conductivity 22% IACS

Beryllium Copper 172 Mechanical Properties

The alloy 172 can withstand extreme loads due to its high yield strength and impact toughness. It also boasts excellent fatigue resistance, allowing it to endure cyclic loading without permanent deformation or failure. This makes it an ideal choice for components that require consistent performance over long periods, such as springs or fasteners used in extreme environments like aerospace or automotive manufacturing plants.

Properties Metric Imperial
Hardness, Rockwell B 80.0 – 85.0 80.0 – 85.0
Tensile strength, ultimate 515 – 585 MPa 74700 – 84800 psi
Tensile strength, yield 275 – 345 MPa 39900 – 50000 psi
Elongation at break 15.0 – 30.0% 15.0 – 30.0%
Modulus of elasticity 125 – 130 GPa 18100 – 18900 ksi
Poissons ratio 0.3 0.3
Machinability (UNS C36000 (free-cutting brass) = 100) 20% 20%
Shear modulus 50.0 GPa 7250 ksi

C17200 Beryllium Copper Equivalent

  • AMS 4651
  • AMS 4725
  • ASTM B194
  • ASTM B196
  • ASTM B197
  • ASTM B570
  • MIL C-21657
  • SAE J461
  • SAE J463
  • UNS C17200

C17200 Beryllium Copper Applications

  • Electrical Components
  • Fasteners
  • Industrial Pumps
  • Bearings
  • Firing Pins
  • Non-Sparking Safety Tools

Beryllium Copper Alloy C17200 Specifications

Beryllium Copper Alloy C17200 Bar AMS 4650, 4651, 4533, ASTM B194, B196, MILITARY MIL-C-21657, SAE J463, J461
Beryllium Copper Alloy C17200 Extrusions ASTM B570
Beryllium Copper Alloy C17200 Forgings AMS 4650, ASTM B570
Beryllium Copper Alloy C17200 Plate ASTM B194
Beryllium Copper Alloy C17200 Rod AMS 4650, 4534, 4533, 4651, ASTM B196, MILITARY MIL-C-21657, SAE J463, J461
Beryllium Copper Alloy C17200 Rod, Beryllium Copper Alloy C17200 Forging AMS 4650
Beryllium Copper Alloy C17200 Sheet ASTM B194
Beryllium Copper Alloy C17200 Strip ASTM B194, SAE J463, J461
Beryllium Copper Alloy C17200 Tube, Beryllium Copper Alloy C17200 Seamless AMS 4535, ASTM B643
Beryllium Copper Alloy C17200 Wire AMS 4725, ASTM B197, SAE J463, J461

C17200 Beryllium Copper Corrosion Resistance

Adding beryllium gives the alloy superior corrosion resistance compared to other UNS C17200, making it suitable for use in marine applications or any environment where exposure to salt water may be a concern. Additionally, the lack of iron content means that beryllium copper 172 does not suffer from galvanic corrosion when exposed to dissimilar metals such as stainless steel and aluminum which can cause premature failure in other materials when subjected to similar conditions.


The machinability rate of C172 copper alloys is 20%.

Heat Treatment & Heat Resistance

Beryllium copper 172 can be heat treated using various methods, including solution heat treatment and ageing treatments. These help maximize hardness while maintaining ductility levels throughout the whole part’s service life cycle, making it suitable for parts requiring tight tolerances or intricate shapes. Additionally, beryllium copper C17200 offers exceptional heat resistance up to 800°C (1472°F). This makes it ideal for soldering or welding  applications, such as electronic components or automotive exhaust systems, where typical materials may fail due to excessive temperatures during operation cycles.


As you can see from this blog post, beryllium copper 172 offers many advantages over other metals, making it an ideal choice for many industries, including aerospace, automotive, and marine engineering industries, where extreme conditions are commonplace. Its combination of physical, chemical, mechanical, corrosion-resistance, heat-treatment & heat-resistance properties gives this material unmatched versatility while providing strong performance guarantees even under harsh conditions. So, if you’re looking for a reliable material that can handle tough jobs, consider investing in beryllium copper 172 today!

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