Metals to use for a Bus Bar???

[kandiman71874]

Stainless steel hardware is used on aluminum so that there isnt a galling or corrosion problem. Zinc plated bolts in aluminum are prone to corrosion problems due to chemical reactions with elements in the atmosphere.

[AMI CUSTOMS]

^^^^ or BRASS hardware which is a better conductor then stainless.

[walwalka]

Those buss bars look fantastic! Nice find

[Dwn4BassAlan]

despite you having chosen already and this thread being so old, but thanks to SnowDrifter we get to revisit and reconsider, I'll try to put the material vs material battle to bed.

aluminum, which has 61% of the conductivity of copper, is normally used because it's cheaper, but it has properties that cause problems when used for wiring. It starts to form a resistive oxide from within the connections, which can cause the terminals on wiring devices to heat up. Also, aluminum can "creep", slowly deforming under a constant load which may or may not be the case for bus bars, but it can eventually cause the connections with devices to loosen, and it also has a different coefficient of thermal expansion compared to the materials used for connections, which speeds up the loosening of connections.

As its been said, you're going for the maximum amount of power the electrical system, as in whatever the alt can possibly produce and whatever the batteries can supply you'll be trying to receive it as efficiently as possible.

But my dilemma is, again, with heat. Heat can cause electrical power loss like it's nobody's business. The power lost in an electrical wire is given by the equation Power = (Current^2 x resistance). So to reduce the power loss, we just have to reduce either the current or the resistance. To reduce the resistance of a wire, it needs to be larger, and if you want you can change the conductor material in it. There will be more metal to carry the current, so the resistance will be lower, and if you upgrade the material you can also reduce resistance. Though you run into a problem, a wire can only be so big before it becomes very difficult to make connections and bend around/through your car. Obviously reducing current in a car audio system would be a bad thing, you'd be trying to solve a power loss issue by essentially "losing" necessary power, right? Wrong. It would only be bad if you couldn't account for the power loss. The advantage is that if you reduce the current by x5, then power loss would be reduced x50, since power loss is (current^2 x resistance) But the problem remains, if you reduce current how can you keep supplying the same power? Well that's where the low-voltage of a cars electrical are somewhat useful because it's not like you need a generator putting out hundreds of volts, you just need the right equipment. So to counteract the the loss of current you just raise your voltage since power is (voltage x current). So, if you have a considerably high car voltage you can reduce the amount of current required drastically, but the problem is being able to get your electrical system to reach and retain a high voltage, but if you can do it, you're set.

So the final bus bar issue comes down to heat yet again. Between aluminum and copper. Take a look at heatsinks, most (consumer ones at least) are traditionally made from aluminum or copper (or some alloy of those). They both do the same job a little differently. Copper is twice as thermally conductive as aluminum, which in this case can be a bad thing, but because I would have more copper I have more material, this has a lot of pros and cons but it basically means that the copper will absorb more heat more quickly than would aluminum, but it would still need to heat up more material than aluminum, and because its heat transfer ability is possibly better, due to the air cooling flow that would have more surface area to remove heat from the copper, though it is denser so it holds more heat inside. So if the bars got to the same temperature the aluminum would cool down faster because of it's lower density, but it also requires less energy to heat it to a certain point. It's not exactly definitive which is positively better because there is no variable for heat transfer from a surface for the surface composition, it only depends on the fluid (air or water) flow and other related properties of the flow, but not the metal/surface, as long as the same surface areas are considered, (which is where the bars might differ in my case, in size, so surface area would not be the same.)

But I've heard a lot of back and forth on the topic, but here's a good example explanation: (ill reduce font to save space, since this is getting spacey lol)

So, because of its higher thermal conductivity copper soaks up more heat more quickly, but because of its higher mass it's going to STAY hot. Aluminum isn't as good at absorbing heat but, because of its lower density and mass, it releases the heat more quickly. So the idea is more mass / greater density = holds onto heat better.
To get the copper block to the same temperature as the aluminum one, more energy must be put into the copper block, because if it is denser (more molecules to heat up) then the same amount of energy will not heat up each molecule as much as in aluminum. So in this example, the copper block must dissipate more energy than the aluminum, and hence the aluminum gets rid of it faster (because they both give off the energy at the same rate to the air), but it requires much more energy to get the copper block at the same temperature.

But even though copper would absorb and hold more heat, its resistance would remain lower and it would not lose as much power as aluminum at a higher temp because of its much higher conductivity.

So in my mind I believe copper would work better, but obviously you can do what you want if it works for you.