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Performance COPPER Alloys

For the past 12 years Performance Copper Alloys have been increasingly used as Valve Seats and Bushings in all types of Motor Sport Racing. From weekend warriors all the way to Top Fuel Dragsters. It is actually hard to find a professional racing format/class where this material, is not used at least as the exhaust seats. In most cases engine builders are using the product on both intake and exhaust. NASCAR, IHRA and NHRA teams using this same alloy because it outperforms any other product on the market, and wear, cracking and erosion problems are non-existent with this particular alloy.

Unleaded Racing Fuels. When NASCAR® made the rule change requiring the use of "unleaded fuel", many teams found that the unleaded fuel formulation caused considerable valve seat deterioration. The NASCAR® teams already running this alloy, which had already been running for other reasons, did not see any problems with the seats with the change in fuel formulation.

HARDNESS

This is one of the more misunderstood and misrepresented phenomenon with copper alloys. Most copper alloys offer high thermal conductivity, high mechanical strength and hardness are from a family of metals considered to be precipitation hardening materials. Another term used to define this heat treatment is an aging process. The specific aging processes are based on the copper alloy chemistry, which when aged in a controlled environment, determines the alloy hardness.

In addition to affecting the chemical structure, the aging process also yields controlled levels of thermal and electrical conductivity. Precipitation hardening is done by heating an alloy to a specific temperature, then holding at that temperature for a predetermined period of time, then air-cooled. For stability reasons aging is done only after a solution annealing process. This means that the alloy properties are changed when exposed to time and temperature while in use—by welding, surface treatments or some incident that heats the component to a temperature above the original aging temperature. Exposure to time and relative temperatures over the original aging temperature for a specific alloy can either increase or decrease the properties of the alloy. An occurrence called over aging can seriously affect the short and long-term performance of copper alloy mold components.

Over aging also can soften materials to surprisingly low levels, where the components will fail because of lack of expected hardness. Or, over aging can reduce elongation and ductility to the point where the component fractures because it is too brittle for an application.

Copper alloys, like steels, provide the most desirable performance characteristics at optimum hardness rather than ultimate hardness.

Some alloy manufacturers provide products at the ultimate hardness in efforts to entice buyers with the highest hardness products. While other manufacturers provide products at the optimum, which in effect allows for the slight increase in hardness and lower ductility as a result of continued aging. Providing products at the ultimate hardness is a disservice to users because the ductility of the product is low—generally 3 percent elongation or less, which when used and exposed to ongoing time and temperature, exhibit even less ductility and eventually fail due to fracture. If someone told you that after running a mold 24/7, your components made of a copper alloy—chosen because it was 38-40 Rockwell “C”—would start fracturing like glass, would you believe them? Those that don’t soon find out that the copper alloys at 30 Rockwell “C” are the superior choice and will yield the longest lasting components. In other words, buyer beware of copper alloys offered at or near 40 Rockwell “C”.

MECHANICAL PROPERTIES:

Tensile Strength	Yield Strength	Compressive Strength	Hardness	Thermal Diffusivity at 20° C cm2 / sec
937.70 MPa	868.63 MPa	744.63 MPa	30 R/C	0.454

COMPOSITION: Beryllium Free