Naked Science Forum

Non Life Sciences => Technology => Topic started by: syhprum on 18/06/2019 13:03:52

Title: How long do nuclear warheads remain servicable after overhaul ?
Post by: syhprum on 18/06/2019 13:03:52

I am sure no official answers are available but presumably it is possible to discus some of the factors involved.
Tritium and polonium both have short half lives and quickly decay, plutonium has numerous crystalline forms and  presumably shape distorts  with varying temperature while conventual explosives may become unstable.
Diagnostics tests can be run on electronics but I would be a little nervous connecting one to my computer.
All these problems before those of the launch vehicle I wonder what delay occurs before the order is received to destroy the target and the target is destroyed. 

Title: Re: How long do nuclear warheads remain servicable after overhaul ?
Post by: alancalverd on 18/06/2019 15:53:38

IIRC the major problem is α-ray damage within the electronics, which generally limits shelf life to around 5 years. But all the sensitive or rapidly-decaying parts are replaceable.

Title: Re: How long do nuclear warheads remain servicable after overhaul ?
Post by: Bored chemist on 18/06/2019 18:49:01

Quote from: alancalverd on 18/06/2019 15:53:38

IIRC the major problem is α-ray damage within the electronics,

Which bits of electronics?

Almost everything is shielded from any alphas by the explosives which surround the plutonium (etc).

Title: Re: How long do nuclear warheads remain servicable after overhaul ?
Post by: jeffreyH on 18/06/2019 19:40:26

What about the effect of alpha particles on the explosive?

Title: Re: How long do nuclear warheads remain servicable after overhaul ?
Post by: Bored chemist on 18/06/2019 20:08:05

Quote from: jeffreyH on 18/06/2019 19:40:26

What about the effect of alpha particles on the explosive?

Instability of the explosives is a different issue but, since plutonium reacts with air, it's always coated with something, and a decent coat of paint will massively reduce the alpha flux.
At worst, the alpha particles could disrupt a very thin layer of the explosive.

Title: Re: How long do nuclear warheads remain servicable after overhaul ?
Post by: evan_au on 19/06/2019 00:11:34

Nuclear weapons states have an ongoing programme of maintenance for their nuclear arsenals.
- This includes sample checks of the components, to ensure that they still meet specifications
- And computer modeling of the behavior
- The National Ignition Facility in the USA is used for testing hydrogen fusion weapons (and also for peaceful purposes)
- According to the atomic museum in Hiroshima, there have been recent "sub-critical" nuclear tests conducted by the USA.

This is despite treaties banning the testing of nuclear weapons in the atmosphere and underground.

See: https://en.wikipedia.org/wiki/Nuclear_weapons_testing
https://en.wikipedia.org/wiki/National_Ignition_Facility