Bob Weber is president of Virginia-based Write Stuff. He is an award-winning freelance automotive and technical writer and photographer with over two decades of journalism experience. He is an ASE-certified Master Automobile Technician, and has worked on automobiles, trucks and small engines. He is a member of the Society of Automotive Engineers (SAE) and numerous other automotive trade associations. He has worked as an auto service technician, a shop manager and a regional manager for an automotive service franchise operation.
Brakes have been around for as long as the wheel. The original friction material was probably Fred Flintstone’s feet. Romans saved their sandals by using wooden blocks pressed against the wheels of their chariots.
The evolution of vehicle brakes has been surprisingly slow. In two millennia, brakes changed very little. In the early days of America, wagons and stagecoaches still used the wooden block and lever brake system.
However slowly, brake technology may never stop evolving.
One of the greatest issues precipitating change is legislation calling for an end to copper in brake pads.
In the 1990s, towns south of San Francisco were having trouble meeting Clean Water Act requirements to reduce copper in urban run-off flowing into San Francisco Bay. Preliminary studies indicated that brake pads were a significant source of that copper. Tiny amounts of copper fall onto the streets and parking lots every time drivers step on their brakes. Then, when it rains, that copper is washed into nearby streams and rivers. Although copper is essential for the health of both plants and animals, excessive amounts are harmful.
The Brake Pad Partnership, a cooperative effort among representatives of the auto industry, brake pad manufacturers, environmental groups, storm water agencies and coastal cities, discovered that the use of brake friction material accounts for anywhere from 35% to 60% of copper in California’s urban watershed run-off. The group’s members determined a course of action that would address the issue. The partnership decided that the most effective and fair thing to do would be to pursue legislation mandating the phased reduction of copper used in brakes.
Copper has long been used as a friction modifier in ceramic formulations. In some brake pads, copper was as much as 20% of material content by weight.ccording to the Copper Development Association, a U.S.-based, not-for-profit association of the global copper industry, copper makes for a smooth braking, transfers heat efficiently and improves stopping in cold weather. Copper also helps prevent squealing and shuddering caused by pad vibration.
As a result of legislation enacted in 2010 in California (SB346) and Washington (SB6557), copper must be reduced to one-half of one percent or completely phased out by 2021 in Washington and 2025 in California.
The Copper Development Association supports the conclusion of the Brake Pad Partnership and its plan to phase out copper from brake pads over a 15-year period.
The evolution of copper-free brake pads has already begun and it will soon affect the entire automotive repair market.
“The automotive industry is shifting to low-copper or no-copper content in braking products,” stated Dr. Mark Phipps, director, R&D and engineering for Bosch Braking Components, North America. “Bosch has been using its patented copper-free ceramic material in the premium grade QuietCast line of braking products since last year,” he added.
OE vehicle manufacturers reportedly began using low- and zero-copper formulations in millions of vehicles in the 2014 model year. As a result, low-copper technology will be coming to all markets, not just Washington and California, on many popular models.