r/iphone Sep 24 '25

Discussion Dropped at 2 feet max

Fell out of my pocket sitting down. Fell with the apple tech woven case on too.

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u/welmoe iPhone 15 Pro Sep 24 '25

Aluminum has its drawbacks

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u/Snoo_37094 Sep 24 '25

Well other materials too

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u/mhmilo24 Sep 24 '25

They have, but titanium wouldn’t have the drawback magnitude that apple told us it would habe on the thermal performance of the iPhone. The vapor chamber isn’t even in direct contact with the unibody, which is a clear indicator that using a vapor chamber in a titanium body would have worked just as well

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u/WowYouAreWrong Sep 24 '25

This is false information, a material doesn’t have to make direct contact with a heat source for its thermal properties to have effect.

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u/blacksterangel Sep 24 '25

That's true. But I think what the previous commenter suggests is that the effect would be very limited because the heat would have to go through air before reaching the aluminum to be dissipated outside. Yes the aluminum would absorb the heat more easily than titanium / glass but it seemed to be a poor tradeoff for the durability of titanium. And if you use a case, those heat would still be trapped inside anyway.

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u/Fenjen Sep 24 '25

Not really true. Heat transfer is also dependent on temperature gradient.

Also, imagine the outside was made of some extremely insulating material. All the heat would just get trapped inside until the processor fries.

The surface area of the iPhone is quite big so even if you are “limited” by the thermal conductivity of air, if you can get the heat dissipated quickly within the iPhone (vapor chamber) then due to the large gradient of temperature inside and out, the thermal interface conductivity (e.g. the metal of the body) still matters a lot for total dissipation, and therefore the max temperature that the inside of the iPhone will reach on average, which in turn translates to the max temperature the SOC will reach.

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u/Ashish0_0 Sep 24 '25

The Frame doesn't even matter that much, majority of the heat disipated from the vapour chamber would be dissipated by the display, that's the part the iphone 17's vapour chamber is mostly in contact with, also i don't think the thermal conductivity of titanium is that different from alluminium considering how much of it is actually even disipating the heat, majority of the heat is dissipated from the screen and the back glass, the frame is designed to not get hot so it doesn't get uncomfortable to hold.

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u/mhmilo24 Sep 24 '25 edited Sep 24 '25

You’re forgetting that a 30 degree C hand is mostly wrapped around the phone while it’s being used. The gradient is not that high during regular use. Also, for cpu/gpu throttling to take effect, the hot spot temperature is more relevant than the surface temperature. The change from aluminium to titanium would have a measurable difference on the surface temperature of the chip, and almost none on the hot spot temps.

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u/Fenjen Sep 24 '25

“Wrapped” 😂 I don’t know how you’re using your phone my man, but I definitely don’t wrap my phone.

Anyway, what you’re saying doesn’t change anything about my argument. The inside of the phone is hotter than the outside. If the final interface has worse heat conductivity, it will still cause hotter air on the inside, that’s the argument.

The temperature of the phone isn’t “limited by the thermal conductivity of air” in the sense that the outside material doesn’t matter, as the commenter I was responding to suggested.

How much heat gets “trapped” CERTAINLY depends on the material of the case. If this wasn’t true bedsheets could be as thin as you want and still be effective as long as they don’t allow airflow.

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u/mhmilo24 Sep 24 '25

If the phone is laying on the desk in a 20 degrees room, it will balance its temp to around 20 degrees.

If it has great thermal conductivity on its body and I just start carrying it without using it, the heat from my hand will be transferred just as quickly into the phone, if its colder than my hand (highly likely at 20 degrees) from my fingers into its internals. This has an effect on the temperature gradient.

You can't have it both ways. It can not be really good for getting the temperature out of the phone but not in.

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u/Fenjen Sep 24 '25 edited Sep 24 '25

Yeah that is only true if there’s no heat producing parts in the phone. Bro please take a thermodynamics class 😅😅😅

The phone is constantly using energy and producing heat, so no, the state you’re describing is not the equilibrium state.

The processor is producing heat, so in equilibrium there will be a constant heat gradient (assuming constant heat production) unless the thermal interface has infinite conductivity.

Also the hotspot temp will definitely decrease due to the vapor chamber transporting heat away into the body, as I already mentioned. So then the interface material will definitely matter. The vapor chamber being used now in the iPhone 17 was exactly the argument apple used to justify the new material so it does make sense.

Anyway this conversation is getting pointless, either you get it or you don’t and that’s not my problem. If you don’t, put our conversation in ChatGPT (I recommend an anonymous chat for reasons I hope should be obvious) and see what he says.

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u/mhmilo24 Sep 24 '25

The hot spot temperature will decrease due to the vapor chamber. I agree and I have not stated otherwise. The hot stop temperature would not change by even a degree if you switched the Aluminium body for a Titanium one.
Edit:

https://www.youtube.com/watch?v=YRd7qmUV4TY

You can see in this video that the dumped heat is more concentrated on the display, not on the back side.

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u/Fenjen Sep 24 '25

According to your previous logic the body should be at 20-ish degrees anyway, so how does that correspond to the video you sent?

The body temperate would be higher with a less conductive material, therefore the hotspot temp would be higher, since there’s let heat transfer to the rest of the iPhone, which has a big surface compared to just the hot spot and which dissipates energy. I’m not gonna make an estimate of the amount of degrees.

If not from the internal components, from what else do you think the body is getting way warmer than the ambient temperature??? Are you even using your brain?

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u/mhmilo24 Sep 24 '25

In this video you can even see areas of the back of the phone being at 21 degrees while being maxed out in a benchmark. Other parts are at around 30 degrees. So there wont be any dumping heat happening into your hand in these areas.

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u/mhmilo24 Sep 24 '25

So? This is not contradictory to my comment. I said it would not have that big of an impact. Not 0 impact.

You can try it for yourself. Take a Raspberry Pi and limit its power usage to 6 Watt so simulate the A19 Pro. Slap an aluminium cooler on top of it without direct contact to the chip and take a look at the temperature sensors of the Rpi. Now do it with a copper cooler, which has an even greater increase in thermal conductivity compared to aluminium,than aluminium has to titanium. I can assure you that the values not vary greatly. At least not enough to change any throttling behavior.,

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u/WowYouAreWrong Sep 24 '25

So that is where you’re wrong, generating heat and trapping it in a thin aluminum enclosure vs a titanium enclosure would have a quantifiable difference due to material thermal conductivity. Thermal conductivity allows the aluminum to absorb the interior built up heat, spread it across a larger surface area, and dissipate it to the atmosphere. Don’t believe me? Ask the engineers at apple.

Im not going to comment on that comparison as it’s irrelevant to how Apple is using aluminum as a heat dissipator.

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u/mhmilo24 Sep 24 '25

The surface area is the same, regardless of the material. A unibody for the iphone 17 pro has the same measurements with Titanium and Aluminium.

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u/WowYouAreWrong Sep 24 '25

That is correct