The big Radiator Material Test: Even more lead, a popular hiding place and 2.5 bright spots | Part 2

1 - Introduction, Brass vs. Copper, brass and equipment 2 - Barrow Dabel 28b Slim 120 mm 3 - Corsair Hydro X-Series XR 5 120 mm 4 - Thermaltake Pacific SR-Series 360 5 - Kafuty Aluminium Radiator (no name) 120 mm 6 - Summary and conclusion

Corsair Hydro X-Series XR 5 120 mm

The second manufacturer in the alphabetically sorted test is Corsair with the Hydro X-Series XR 5 120 mm. It is well known that Corsair has things done and so we actually find Hardware Labs in the current model.

00a Box

00b Front

00c ISO

Let’s also let Corsair have their say before I comment further, although the English original differs slightly, because they write about a copper core without explicitly naming the channels. And I refer you to the first page of the article and the classification of copper and brass on the international market. Because it caught up with me faster than I thought:

Pre-chamber, inlet and plumb bob

Let’s be surprised and open this radiator again at the pre-chamber (tank). The solder joints of the cooling channels are barely oxidized and not visibly scaled. The solder is all-round and well distributed. The bottom line is that this is very good.

The solder at this point is without criticism, because I find pure tin, so no lead. The tin is also clean on the surface and I didn’t even have to scrape away oxide and scale as I did with Barrow.

The walls of the antechamber are also without complaint, because CuZn40 is still proper brass. So up to this point, everything is also in the deep green range and there is nothing to criticize.

But now we come to a certain point where the wheat is separated from the chaff, namely at the threaded inserts for the fittings, which were previously soldered or pressed into the chamber. The addition of around 2% zinc increases the strength of the alloy compared to pure copper. However, I will have to ask again and contact the manufacturer because I think this solution is at least unusual and don’t want to make a mistake.

The soldered thread insert is made of brass with almost 46% zinc by weight. Anything less than 50% zinc will remain supple enough to withstand the force of screwing in the fittings nonchalantly.

Cooling channels and cooling fins

Now we come to the cooling channels and the fins soldered to them. If you cut the whole thing open, the usual picture emerges and you can admire the fins, which are only 25 µm thick.

The cooling channels are made of common yellow brass (CuZn36). This can be left as it is, especially as the walls are significantly thinner than those of most competitors. Incidentally, this also applies to the current radiators from Hardware Labs. If you like it thicker, you’ll have to go for copper if you want the same performance.

The cooling fins are made of pure copper, because brass would break more easily here, as it would also be much more brittle due to the zinc. With a thickness of only 25 µm, nothing can be slit (I’ll show you the side view here), but here too the density of the extra-thin fins and the geometry are only an important but successful compromise in order not to have too restrictive an effect on the fan. Cooling surface vs. pressure loss. It’s always the same balancing act.

Frame and screws

The frame here is made of CuZn40 because the inside is already strong enough. With this size, it is already durable enough.

The screws, on the other hand, are only made of non-alloy steel and are therefore much softer. However, since you screw into brass, this is more than sufficient.

Summary and interim conclusion

The quality is right, especially the soldering quality is exemplary. And where others still use hidden lead, here copper to keep the fittings in check. The cooling fins are extremely thin, so more of them fit in. Clever solution. Leaving aside the performance, which should certainly be very good, the wording from Hardware Labs fits better, of course, where the “copper” is completely excluded except for the fins. Corsair’s marketing, on the other hand, couldn’t resist this and so the well-behaved US customer buys copper instead of brass. Of course, this doesn’t detract from the functionality, it just serves the market. I would have left it alone, especially as the German translation also includes the word Kanäle. This, in turn, should really be adapted, because it is simply not correct.