What problems are you trying to prevent / avoid. Friction material development tends to be a rather complicated science. If you can be a bit more specific, the CR4 board users maybe able to be of better service.
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"Your theory is crazy, but it's not crazy enough to be true." - Niels Bohr
I am assuming from the use of your words "brake lining" that you are referring to drum brakes (with the expanding shoes). If that is the case, here's an old trick the North Carolina boys used to do back in the days of stock car racing; the forerunner of Nascar, Winston Cup, et. al. Take a hacksaw and cut slits right across the brake lining, right down to the backing steel. Space them about 2" apart. I never heard an explanation as to why this works, but it increases the stopping power and reduces brake fade. It also makes the brakes last longer and, for a race car, that's especially good.
Actually linings refer to both pad (disc) linings and shoe (drum) linings. The slots improve pressure distribution in both lining applications. This in turn improves both stopping power (since more friction is touching the braking surface) and lessens the potential for noise problems (more stable contact area). The only efficient cooling mechanism in brake design are the vents in disc brake design.
fm!
__________________
"Your theory is crazy, but it's not crazy enough to be true." - Niels Bohr