On January 21, 2015, EPA, states, and the automotive and heavy-duty industry signed an agreement to reduce the use of copper and other materials in motor vehicle brake pads. The next benchmark of the initiative will take effect in 2021.
The agreement calls for reducing copper in brake pads to < 5 percent by weight in 2021 and 0.5 percent by 2025. In addition to copper, this voluntary initiative reduces mercury, lead, cadmium, asbestiform fibers, and chromium-six salts in motor vehicle brake pads.
The initiative will decrease the runoff of these materials from roads into the nation’s streams, rivers, and lakes. Copper from stormwater runoff can affect fish, amphibians, invertebrates, and plants.
Why Was Copper Used in Brakes
According to a study that was published on ScienceDirect.com, manufacturers of heavy-duty and automotive brake material used copper because it contributes to good brake performance properties in addition to providing good thermal conductivity.
The study revealed, “Microstructural investigations of copper chips at the surfaces of brake pads revealed a zone of severe plastic deformation which provides high hardness, but there is also evidence of recrystallized copper nano-particles which are incorporated into friction layers as soft ingredient once detached from the pad surface.”
Thus copper seems to play a dual role, the study also found that copper “firstly is a reinforcing element of the brake pad providing primary contact sites, and secondly as a solid lubricant by contributing to the formation of a layer of granular material providing velocity accommodation between the rotating disc and fixed pad.”
The material properties of solid lubricant particles like copper determine conditions for friction force stabilization and smooth sliding behavior. Copper is much cheaper than silver, which is an alternative that works as well but is too expensive to use, and provided heavy-duty manufacturers with a combination of braking performance and longevity due to its lubricating attributes.
The Impact on Heavy-Duty Brake Manufacturers
The one thing that all manufacturers are required to do is produce brakes that meet the current stopping distance laws which have not changed. Under the current laws in North America, commercial vehicles are “required to stop in not more than 250 feet when loaded to their gross vehicle weight rating (GVWR) and tested at a speed of 60 miles per hour (mph).”
New materials with reduced or no copper must meet current laws, and the performance of the friction material must meet or exceed past performance otherwise heavy-duty manufacturers risk losing market share.
The Copper-Free Initiative 2021 deadline impacts air disc brakes more than S-Cam Drum Brakes. Many commercial vehicle OEM formulations for drum brakes already meet 2025 requirements for reduced copper therefore they are not particularly concerned with the 2021 deadline.
Drum brakes operate at lower temperatures, which allowed non-copper formulas to be used and absorb and dissipate heat energy, which makes it easier for drum brake linings to be produced with little to no copper.
Meeting the Standard Nationwide
Fleets who have trucks that work in multiple-states will specify brakes that meet the requirements of the Copper-Free Initiative even though only two West Coast states are tied to the agreement.
This means that friction material and brake manufacturers will have to roll out compliant friction material nationwide to avoid having brakes that are compliant only in select states.
As environmental issues continue to dominate the political landscape, the Democrats successfully securing the White House with Joe Biden as President starting in 2021 may mean that there will be more focus on these issues that impact the heavy-duty truck and trailer industry. By 2025 it is likely that we will see additional mandates similar to the Copper-Free Initiative being adopted by more states and by extension this will have an impact on Canada as well.
Heavy-Duty Parts Distributors Educate Your Customers
When replacement parts are manufactured to different specifications the inevitable result is that the performance of those parts changes. That change can be an improvement, but it also can mean that it declines in specific areas.
It is important that sales representatives and parts technicians are able to articulate what is changing and how that may impact the performance of the air disc brake replacement parts which are impacted the most by the Copper-Free Initiative.
It is important that distribution companies that work with fleets on a daily basis also monitor what impact these new brake formulas have in the real world conditions that commercial vehicles operate in and report that information back to the manufacturers.
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