Thermalloy C-900

CAL C900 is Copper Nickel Chromium Silicon alloy which can be heat treated by means of precipitation hardening to produce high strength and a range of thermal conductivity properties to accommodate a range of applications.

CAL C900 is the highest strength of this family of alloys close to Beryllium Copper (CuBe/BeCu) with the added advantage of greater hardness retention at elevated temperature which is important for high speed production for injection moulding applications.

Tests have shown that it is more than 4 times more conductive than 420 stainless steel, when used in injection moulding equipment and 25% better than CuBe.

The alloy also maintains its hardness and mechanical strength at higher temperatures and for longer periods than Beryllium Copper. (See graphs below).

Beryllium Copper starts to lose hardness rapidly after temperatures exceed approximately 350°C (662°F).

Despite their high strength, all of the Elite Thermal Alloys are completely resistant to hydrogen embrittlement.

They also would be an excellent choice for aggressive marine environments, possessing excellent corrosion resistance.

Discuss your CAL C900 requirements

Mechanical & Conductivity Properties

• Copper-Nickel-Chromium-Silicon-Alloy
• CuNi2SiCr

Table 1 – Typical Mechanical and Conductivity Properties

Rod, Bar and Tube for Standard Tempers

CAL C900 Applications

Carefully controlled adjustments in composition and process parameters result in the three distinct Elite Thermal Alloys. This gives designers the opportunity to optimise material selection for their particular applications.

• Marine applications requiring high strength coupled with excellent corrosion resistance.
• Aerospace components, such as landing gear bushings and sleeves and bearing retainer rings. .
• It can be used in the manufacture of mould components for the plastic, Zinc and Aluminium injection die casting market where its high heat conductivity over conventional tool steels offers distinct advantages for high production rates.
• The alloy is utilised extensively in the motor racing circuit for valve guides and valve seats where high strength, wear and conductivity are important properties.
• It is also used for electrical application in welding, for electrode holders, spot electrodes, projection and butt welding dies principally for stainless steel and Monel.
• Other electrical applications include heavy duty switch gear components where greater strength is required than conventional high conductivity copper.
• For high stressed structures and wear resistant parts such as bevel gears, worm wheels, valves, bolts and general fasteners.

Discuss your CAL C900 requirements

Availability and Formats

The Elite Thermal Alloys can be supplied in the form of forgings, rounds, blocks, rings and tube to a maximum piece weight of 6000kgs.

The product can also be supplied in bar form in standard lengths.

Copper Alloys is experienced in fully machined components designed for the most extreme engineering applications and can support with turnkey precision machined components.

The Elite Alloys come in three groups:

• Bars (square/flat/round) from 10mm to 500mm (0.375″-20″) in section
• Forgings (to 5 Tonnes): Blocks/Rings to 2400mm (8ft) outer ø / Shafts to 7M (23ft) long / Discs to 1250mm (50″) ø
• Proof machined or fully machined components

Chemical Composition

• Copper-Nickel-Chromium-Silicon-Alloy
• CuNi2SiCr

Table 2 – Elite Thermal Alloy Chemical Composition (weight percentage)

* For reference only – does not form part of the acceptance criteria unless agreed.

Hardening Mechanism

Highly Engineered Alloys for Extreme Environments

Scientific control of precipitation hardening particles from solution enable extreme hardness to be achieved without impacting conductivity.

For most other alloys, there is a compromise between the two, for the first time, the Elite Thermal Alloys, in particular CAL C900 possesses both. The increased conductivity is enhanced by primary and secondary precipitating mechanisms.

The ageing for CuNiSiCr C900 is very complex and there are two hardening mechanisms precipitation hardening by the formation of Ni2Si,Cr3Si and Cr5Si2 and spinodial decompostion. Through precise control of ageing temperatures, Copper Alloys can maximise the electrical and thermal conductivity properties using both hardening mechanism whilst still achieving the highest mechanical properties.

The comprehensive employment of highly engineered process technology is revealed by the ability of CAL C900 to maintain its hardness at elevated temperatures, as shown in the charts below.

Discuss your CAL C900 requirements

Physical Properties

• Copper-Nickel-Chromium-Silicon-Alloy
• CuNi2SiCr

Table 3 – Physical Properties of Elite Thermal Alloys

Additional information can be provided upon request

Corrosion Resistant

This family of alloys, in addition to its corrosion resistance in sea water it can be used in most industrial atmospheres and can be used for components coming into contact with non-oxidising acids and salt solutions.

• High resistance to seawater corrosion and industrial atmospheres.
• Excellent all-round corrosion resistance.
• Immune to hydrogen embrittlement.

Discuss your CAL C900 requirements

Mechanical Properties

• Copper-Nickel-Chromium-Silicon-Alloy
• CuNi2SiCr

Table 1 – Guaranteed Minimum Mechanical Properties

Every batch of forgings is certified to BS EN 10204.3.1 as standard using prolongated test pieces selected from each batch of forgings.

All material can be supplied ultrasonically tested to international requirements.

Copper Alloys manufactures a number of alloys in the CuNiSi family which exhibit varying properties of strength and conductivity to suit customer’s requirements.

Inspection and Certification

Full chemical analysis performed on every cast to ensure compliance with table 1.

Each batch (same size/same cast/same process-run) is mechanically tested to ensure compliance with minimum mechanical property requirements in table 2, which exceed the generic specification requirements.

100% ultrasonic inspection as standard – most test standards and acceptance criteria can be accommodated. Certification provided as standard in both wet-signed and electronic form (soft-copy) in accordance with EN 10204 type 3.1. 3.2 Certification can also be provided.

Detailed Specifications

• Copper-Nickel-Chromium-Silicon-Alloy
• CuNi2SiCr

Table 2 – Detailed Specifications