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Anodised aluminium
- Thread starter Samtb
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The 7000 series anodized aluminum that Apple uses on their iPhones and Apple Watch Sport cases is extremely durable and corrosion resistant. I have owned many products with anodized aluminum from Apple, and I have beenimpressed with how resilient it is again scratches. The drawback to anodized aluminum, once it scratches, it's permanent. Also, anodized aluminum helps dissipate heat from causing internal damage when a battery/component temperature increases.
The best? No, because I don't think a definitive answer to that can be given. The most practical and one of the best choices that balances desirable properties? Arguably. If we wanted something that has a near indestructible finish, we could choose Bohler M390 PM steel in a stonewashed finish. However, the weight, the heat dissipation, and the extremely high cost might all be problematic.
Is Apple using their 7000-series alloy across their entire spectrum of products? A metallurgist would be better to comment on this than I, but, if so, to my understanding, the aluminum alloys comprising the 7000 family offer outstanding performance characteristics.
In my experience, I find (good) anodized finishes provide good overall performance. The finishes are reasonably durable, resistant to cosmetic damage, resistant to color changes brought on by UV lighting, and requires minimal upkeep from the User. Apple's anodized finishes have also shone us a great ability to withstand significant color changes that can be brought on by the oils in hands (that can cause some other finishes to darken and become shiny.) A bare stonewashed finish is arguably the most durable (partly because you simply can't discern most cosmetic damage from the finishing itself), but this is not nearly as attractive (and it would also necessitate using a material with considerable corrosion resistance, and IIRC most of the 7000-series alloys are geared more towards strength at the expense of corrosion resistance.)
Is Apple using their 7000-series alloy across their entire spectrum of products? A metallurgist would be better to comment on this than I, but, if so, to my understanding, the aluminum alloys comprising the 7000 family offer outstanding performance characteristics.
In my experience, I find (good) anodized finishes provide good overall performance. The finishes are reasonably durable, resistant to cosmetic damage, resistant to color changes brought on by UV lighting, and requires minimal upkeep from the User. Apple's anodized finishes have also shone us a great ability to withstand significant color changes that can be brought on by the oils in hands (that can cause some other finishes to darken and become shiny.) A bare stonewashed finish is arguably the most durable (partly because you simply can't discern most cosmetic damage from the finishing itself), but this is not nearly as attractive (and it would also necessitate using a material with considerable corrosion resistance, and IIRC most of the 7000-series alloys are geared more towards strength at the expense of corrosion resistance.)
Apple probably uses aluminium mainly due to finish coating options and ease/cost of manufacturing compared to magnesium which has similar characteristics and equally pros and cons for both materials (weight, strength, impact resistance etc)
It would be interesting with the benefit of hindsight if Apple started over if they would opted for Magnesium over Ali given that mac shells were evolved from a prototyping cases and not 100% bottom up material selection
Heat dissipation from Ali is a bit of a red herring as its equally a hindrance as it is a pro. Thermal design only considers the casing material as secondary and you will be lucky if it contributes as much as 15% and in other areas of the laptop it has to be shielded or components moved to avoid hot spots
It would be interesting with the benefit of hindsight if Apple started over if they would opted for Magnesium over Ali given that mac shells were evolved from a prototyping cases and not 100% bottom up material selection
Heat dissipation from Ali is a bit of a red herring as its equally a hindrance as it is a pro. Thermal design only considers the casing material as secondary and you will be lucky if it contributes as much as 15% and in other areas of the laptop it has to be shielded or components moved to avoid hot spots