China's New Rare Earth and Magnet Restrictions Threaten US Defense Supply Chains

Re:China's New Rare Earth and Magnet Restrictions Threaten U... by rzerowan on Sunday October 12, 2025 @03:57AM (#45556236)

At the scale and specificity , lets take magnets - theres magnets and theres magnets , if youre using them in mil/aero tolerances required are going to be much higher with lower failure rates. Think the way rad-hardened cpus for satellites are different/costlier from commercial ones , similarly here when your'e in guidance systems and radars the tolerances require much higher specs than headphones. With the caveat that those already in current products can be recycled so thats one path for simple RE. For the ones that are combined into alloys though its a bigger ask , this i guess will be the main cost increase , as its like trying to separate out copper from bronze if one wants to try recycling. And in mil there are quite a number of special RE alloy to get specific properties. Which is why for the volumes required even at low % alternate refiners will take time to ramp up , in the interim prices dictated at market rates will definately spike.

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Re:China's New Rare Earth and Magnet Restrictions Threaten U... by YZF on Sunday October 12, 2025 @03:56PM (#45561287)

I would guess that the part list of the F-35 isn't publicly available but this sort of implies someone who worked on the design of that airplane chose an alloy or a part knowing that it 100% depends on something that's only available from China. I just find it hard to believe.

( https://www.politico.com/news/2022/10/07/pentagon-f-35-deliv... is related )

What does sound plausible is that some mil-spec actuator (let's say a pneumatic actuator or a motor) happens to have a magnet from China in it. That is not a big deal.

I find it hard to believe that a US mechanical engineer working on the F-35 part would spec an alloy that is only available from China as some fundamental part of the design. E.g. a wing, or body panels, etc. I don't have direct experience but from knowledge working in other manufacturing industries engineers tend to prefer locally available alloys as they're more familiar with their properties and they can easily get them for prototyping purposes Now if the entire wing of the F-35 is subcontracted to China then you'd expect Chinese alloys in that wing. Many products are subcontracted to China and so it's no surprise they'll have Chinese made magnets, alloys etc. But weapons systems are generally not. High end weapons systems like the F-35 may have some secret materials in them that are designed as part of that program and manufactures locally. I guess it's theoretically possible they use some raw materials from China but those being irreplaceable at any cost (when you're talking billion dollar systems and relatively low quantity) also doesn't pass the smell test.

What would settle this question is us getting a BOM of the F-35 with the specific parts/materials that are a concern. We're obviously not gonna get that. Alternatively some sort of reliable source, like head of engineering for one of these companies. I don't think we've seen this either.

The simplest explanation is that saying this impacts something like the F-35 sells more newspapers or advances some agenda. I'd buy the economic leverage argument; just not the national security one. Not without more evidence.

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