Why nickel plated ramsinks?

[beatle]

I noticed that the Tweakmonster ramsinks are nickel plated. Why? If it gives a better appearance, that's one thing, but isn't nickel considerably further down on the conductivity scale? Seems like raw copper would provide better performance for less. They won't be exposed to the elements, so oxidation would be of no more concern than a copper heatsink for your cpu.

 

[dannybin1742]

nickel prevents oxidation of the metal

 

[LED]

Haven't seen or read about them but are you sure it's not silver?

 

[Lizardman]

its not silver. Its nickel.

 

[beatle]

If it were silver I'd agree with it, since silver conducts heat better than copper. Here are the sinks in question.

Why would oxidation be a problem in a fairly dry, climate controlled environment like your computer case? It's obviously not a problem for copper cpu heatsinks like the SK7.

 

[mEarles]

it looks cooler than plain copper, and sadly, that is what sells them

 

[LED]

Originally posted by: mEarles
it looks cooler than plain copper, and sadly, that is what sells them

Then why not plate it Chrome???

 

[Drewpy]

Because nickel plating is thinner than chroming, reducing the impact of its reduced thermal conductivity. If they were made of plain copper they won't totally corrode and go green. But it will become noticeably duller in appearance. And why have dull looking copper sinks when you can have nice shiny nickel plated ones.

 

[beatle]

Like I said before, why don't cpu heatsinks such as the SK7 have some kind of plating if it's important to protect against oxidation? I have an old OCZ gladiator that is all copper. It's not a green monster, despite being almost 2 years old.

 

[Brian48]

Originally posted by: Drewpy
Because nickel plating is thinner than chroming, reducing the impact of its reduced thermal conductivity. If they were made of plain copper they won't totally corrode and go green. But it will become noticeably duller in appearance. And why have dull looking copper sinks when you can have nice shiny nickel plated ones.

It's all about cost, but there's something else too. Firearms/gun bluing and finishing used to be a hobby of mine. Chrome is not easy to plate on most surfaces. In order to plate an object with Chrome, you first need to plate it with very soft copper or similiar metal. The chrome plating is then adhered to this "primer". This is very expensive for heatsinks that are aluminum/copper hybrids and even for full copper heatsinks like the SLK-800 because the degree of tensile strength used for the heatsink is different than the one used for the plating. It's just not cost effective.

Electroless nickel-plating is a little bit easier as there's no baking process to bond the metal coat. The object is simply submerged in a special, metal oxide solution and when an electric current is run through the solution, the nickel molecules "stick" to the object and hence, you have your nickel plating. Nickel plating is very tough when done right, but it's function is more cosmetic than practical since heatsinks don't encounter the same corrosion problems that carbon steel guns do.

EDIT: Oh yes. I forgot. Nickel plating has one very severe drawback. Unless you have a very thick piece of metal, the plated object has a tendency to become brittle and crack. Copper and/or aluminum will lose all of it's flexibility. Fins on heatsinks, especially the copper ones, are extremely thin. You could easily break it after a few times of installing/deinstalling it from your motherboard. Gun owners who reload their own ammunition will know EXACTLY what I'm talking about if they've ever tried to reuse nickel-plated brass more than a couple of times.

 

[CaptnKirk]

Lots of Nickel plated electro-mechanical components in the aerospace computer omponent world - used to inhibit oxidation and corrosion at elevated temperatures, and to avoid moisture exposure from condensation. The plating tends to be only about 0.0005 to 0.001 thick (yes 1/2 to 1 thousandth)
Used frequently where a liquid cooling solution is the thermal exchange medium (not water) and temperatures need to be held stable, but elevated.
Think about maintaining a 50C system temperature when the outside temp is - 73C. Moisture turns to ice and can cause system damage.

EDIT: SEE COMMENTS BELOW -

Nickel plating is CHEAP, and gives a semi-chromed appearance, and it is VERY HARD and durable, if anyone that sanded it off knows.
It all comes down to . . . . .EYECANDY !

 

[beatle]

This still begs the question why it's used on heatsinks designed for passive cooling. Watercooled, extreme temps, etc. are irrelevant in the context of the environment in which these sinks are to be used. They are not subject to any of these harsh conditions.

 

[Ilmater]

Originally posted by: beatle
This still begs the question why it's used on heatsinks designed for passive cooling. Watercooled, extreme temps, etc. are irrelevant in the context of the environment in which these sinks are to be used. They are not subject to any of these harsh conditions.

It's still looks. Yeah, copper looks really cool at first, but over time it will dull. Nickel will not. If they could only plate the top and sides and not the bottom, I'd be happier, but they don't, so I deal with it. I just sanded the bottom of my COrb to get through the nickel. It was a GRUELING process, I can tell you. But, in the end, the top of the will look good forever, but the bottom won't. I don't really care about how the bottom looks though, do I?

Tonight I start going through my Tweakmonsters and my other COrb for my GPU (The first one was placed on my NB).

 

[mrman3k]

I was wondering if there are any recommended sealers for copper heatsinks so that they do not lose their luster so they always look new?