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This is a follow-up for the aluminum bar question here: Aluminum bus bars connection to PCB

My design now is based on copper - low resistance, assembly by soldering. For now, this is probably the best. Yet, there are two contacts that I have no choice but to make of aluminum due to the cost involved with copper machining (big chunks cost a lot).

How do I connect aluminum and copper? Do I need to plate either of those with nickel or some other material? Even perhaps gold. Should i solder or press them?

The key requirement - reliability of the joint. The current that will flow there will be between 500A and 1000A.

TQQQ
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    Hello again! Have you investigated any standards / regulations / best practices for this project? 500A+ and lord knows how many volts doesn't sound like something I'd like erupting into an electrical fire because I'd asked some people on the internet about it. – Tim Williams Mar 03 '23 at 21:43
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    @TimWilliams thank you for your concern. Yes, i am talking to different people, constantly looking on internet and eventually am going through UL. But at certain points the most effective way of getting ideas is asking on the forum. Voltage is fairly low at this time, before UL all tests will be conducted at 24V. – TQQQ Mar 03 '23 at 22:03

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How do I connect aluminum and copper?

Dissimilar metals can have issues with galvanic corrosion, especially in the presence of water/humidity. Plating can help. Another option that I've used in the past is to make both metals the same (but not always possible like you mentioned)

Electroless nickel plating can provide a robust solution to corrosive attack across a range of corrosive mechanisms including galvanic corrosion, chemical attack and erosion. Electroless nickel plating (EN) can be applied to a wide range of basis metals including steel, copper, brass and aluminum alloys. Electroless Nickel plating is currently utilized to promote corrosion protection performance across a diverse range of industries including heavy equipment, oil & gas, power transmission & distribution, automotive, marine and railway to name a few.

Source: https://advancedplatingtech.com/blog/corrosion-protection-benefits-electroless-nickel-plating/

Here is a chart on galvanic corrosion compatibility:

enter image description here Source: https://torksystems.com/Article/ask-the-experts-electrolysis-galvanic-corrosion/

Voltage Spike
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