4 ms·

What is the article talking about when they say "radiation-hardened materials"? What kind of materials might that be?

jjoonathan 9y ago
"Neutron embrittlement" is a term to chase down. Generally people talk about the effects on metal, but I'm sure neutrons affect ceramics, too.
- ghaff 9y ago
  One of the issues with metal is that it starts out as a ductile material and neutrons can embrittle it by introducing voids and dislocations. (i.e. basically moving the atoms around from their ordered crystal state) I'm sure some of the same mechanisms apply to ceramics but they're fairly brittle to start with so designs/applications using ceramics need to account for the fact that they're brittle from Day One.
perlgeek 9y ago
I don't know what they did in this particular instance, but basically there are two things you can do: shield, or in the case of electronics, use larger parts. The smaller some piece of electronics is, the smaller the charges in there are, and the easier it is to introduce errors with ionizing radiation.
- _ph_ 9y ago
  And the design of the electronics might help with radiation tolerance. Computation paths could be redundant to detect/eliminate bit flips due to radiaton. (Some server Power cpus seem to run parallel in pairs, comparing the output at critical parts to detect cpu errors)
  - rurban 9y ago
    Basically the same as in space exploration. Also running at very low MHz.
- FiatLuxDave 9y ago
  There is a third thing, which is to use a dopant which reduces minority carrier lifetime and provides radiation resistance when manufacturing the semi-conductor. Platinum works really well for this. Unfortunately, this can be a poor engineering tradeoff for some kinds of electronics (power transistors for example) and usually increases electrical resistance. AFAIK nobody manufactures platinum-doped microprocessors. I used to be a product manager for radiation measurement electronics, and we used platinum-doped diodes for the part intended to go in the beam. See for example: https://academic.oup.com/rpd/article-abstract/17/1-4/527/3113874 https://academic.oup.com/rpd/article-abstract/17/1-4/527/311... http://ieeexplore.ieee.org/document/5436014/ http://ieeexplore.ieee.org/document/5436014/

"Neutron embrittlement" is a term to chase down. Generally people talk about the effects on metal, but I'm sure neutrons affect ceramics, too.

ghaff 9y ago
One of the issues with metal is that it starts out as a ductile material and neutrons can embrittle it by introducing voids and dislocations. (i.e. basically moving the atoms around from their ordered crystal state) I'm sure some of the same mechanisms apply to ceramics but they're fairly brittle to start with so designs/applications using ceramics need to account for the fact that they're brittle from Day One.

perlgeek 9y ago

I don't know what they did in this particular instance, but basically there are two things you can do: shield, or in the case of electronics, use larger parts. The smaller some piece of electronics is, the smaller the charges in there are, and the easier it is to introduce errors with ionizing radiation.

_ph_ 9y ago
And the design of the electronics might help with radiation tolerance. Computation paths could be redundant to detect/eliminate bit flips due to radiaton. (Some server Power cpus seem to run parallel in pairs, comparing the output at critical parts to detect cpu errors)
- rurban 9y ago
  Basically the same as in space exploration. Also running at very low MHz.
FiatLuxDave 9y ago
There is a third thing, which is to use a dopant which reduces minority carrier lifetime and provides radiation resistance when manufacturing the semi-conductor. Platinum works really well for this. Unfortunately, this can be a poor engineering tradeoff for some kinds of electronics (power transistors for example) and usually increases electrical resistance. AFAIK nobody manufactures platinum-doped microprocessors. I used to be a product manager for radiation measurement electronics, and we used platinum-doped diodes for the part intended to go in the beam. See for example: https://academic.oup.com/rpd/article-abstract/17/1-4/527/3113874 https://academic.oup.com/rpd/article-abstract/17/1-4/527/311... http://ieeexplore.ieee.org/document/5436014/ http://ieeexplore.ieee.org/document/5436014/