In the field of PC cooling , we all know that copper is the most used material for its heat conductive properties, and together with aluminum it makes up the vast majority of heatsinks out there. However, PC cases are made primarily from SECC steel , and in some cases aluminum, so why isn’t copper used to make PC cases ?
Thermal conductivity is a physical property of materials that measures the ability to conduct heat; It is measured in W / mK (watts per meter Kelvin), and a conductivity of 1 W / mK indicates that a quantity of heat of one Joule is propagated through the material in just 1 second. Copper, despite not being the material with the highest thermal conductivity, is one of the most widely used because it is very common and easy to obtain, as well as very malleable and easy to use to manufacture components.
Copper has a thermal conductivity of 385 W / mK, while aluminum – much cheaper – has a conductivity of 205 W / mK. For its part, steel has a conductivity of only 50.2 W / mK, much lower than copper or aluminum, and yet it is the material used to manufacture most PC cases. Why is it like this?
PC cases are not heatsinks
Actually, the function of the PC case is not to dissipate heat, but to accommodate the rest of the hardware components that make up the PC. To dissipate the heat from the components, we already have the heatsinks of the graphics cards, processors, and of course the fans that are installed in the case, but a PC case is not in contact with the components that generate heat and therefore so much it would be absurd, or rather inefficient, to make PC cases with copper.
There are some boxes that are made of more conductive materials, especially aluminum, but they are specific models, generally in mini ITX format like those manufactured by Streacom, in which the processor heatsink is passive and is attached to the box itself. PC to dissipate heat. The same happens with the design of Apple‘s Mac Mini, whose body is made of aluminum because they act as a passive heatsink for the internal components … but look at the size of these PCs.
Copper is a much more expensive material than steel
The price of copper, at the time of writing, is $ 6.54 per kilogram. For its part, aluminum has a price of 1.83 dollars per kilogram, and steel has a cost that varies a lot depending on the type (as you know there are stainless, 316 stainless, laminated, SECC, etc.), but steel SECC (galvanized) is around $ 0.86 per kilogram approximately.
Thus, as you will already understand, it is much cheaper for the manufacturer to use SECC steel to manufacture the PC cases than aluminum or copper, simply because of the cost of the materials. Also, keep in mind that when we talk about a PC case, it can easily have between 2 and 3 Kg of this material, so making copper PC cases would be quite expensive.
Copper is more brittle and withstands less pressure
Continuing with the manufacture of PC cases, SECC steel is much more malleable than copper or aluminum, so it is much easier to make PC cases using this material. Similarly, steel is harder, withstands pressure better, has much more toughness (it is the ability to resist an external force without breaking, that is, it is much less brittle) and, in general, it is a material that due to its properties is much more suitable for manufacturing a component such as a PC case than copper.
So, if you have ever wondered why copper boxes are not manufactured, you already have the answer. The summary is that copper is less indicated for its physical properties (toughness, malleability, etc.), it is much more expensive and, in addition, it would be inefficient since the function of a PC case is not to dissipate heat as such, even if it participates passively in cooling a PC.