7 ms·

Proton irradiation decelerates intergranular corrosion of Ni-Cr alloys

PaulHoule 6y ago
Note that materials and salts like this could be used for Thorium based nuclear energy and of course you get the irradiation for free.
- deleted 6y ago
  [deleted]
- tlb 6y ago
  Thorium reactors generate beta particles, gamma rays, and neutrons, not the protons used in the study. They conjecture that neutrons will have a similar effect, but haven't tested it.
  - jojobas 6y ago
    It's guaranteed to have a different effect, neutron capture will manifest in different isotopes with different products.
- irjustin 6y ago
  > Proton irradiation-decelerated intergranular corrosion This is specifically proton irradiation as opposed to neutron. It doesn't appear to come for free.
  - rsfern 6y ago
    At the end of the discussion section, there is some evidence presented that this self-healing effect occurs under neutron irradiation as well, though the exact implications for fast reactor materials seem unclear. Makes sense, the basic mechanism seems to be mediated by increased interstitial diffusion. Shouldn’t really matter if it’s protons or neutrons that are generating those interstitials Edit: on re-reading, it doesn’t seem that they’ve actually performed any neutron irradiation experiments
    - benzofuran 6y ago
      Neutron radiation leads to embrittlement in many materials, so the long term effects will have to be considered in addition to short term corrosion rate improvements.
      - rsfern 6y ago
        That’s a really good point, and I agree, but any alloy used for reactor components is going to have to deal with embrittlement one way or another. At the end of the day this is just another potential tool in the alloy design toolbox, and it might or might not turn out to be useful for mitigating corrosion in reactor materials
- acidburnNSA 6y ago
  Also, nearly identically, in uranium-based molten salt reactors. The safety and sustainability that enticed e.g. Andrew Yang to like thorium are actually coming from low-pressure coolant and the concept of breeding, both of which are possible with thorium or uranium fuel cycles. The thorium itself has nearly nothing to do with either benefit. It's basically a rebranding of non-light water reactor nuclear. Thorium has one major primary physical differentiator, which is that it alone allows breeding with slow neutrons. Uranium needs fast neutrons to breed. Both options have pros and cons that basically wash out.
  - PaulHoule 6y ago
    Th and U are soluble in F salts, but Pu isn't. A molten salt reactor that breeds U238 would have to be based on a Cl chemistry which is not so developed. Otherwise you'd get Pu plating out on your heat exchangers, clogging pipes, etc. What makes the LWR non-viable since 1980 or so is not the uranium or even the LWR, but the steam turbine it is attached to. The power density of a steam turbine is at least an order magnitude less than that of the gas turbines that are used to generate electricity today. To a first approximation, the cost of something is proportional to it's volume or mass. As it turns out, even if the heat was free the steam turbine alone attached to an LWR would make the cost of electricity uncompetitive. In fact, this is what mostly killed coal. If nuclear power is going to have any economic impact we have to ditch the steam turbine for a closed-cycle gas turbine and ditch the LWR for something that operates at higher temperature. Unfortunately the last time people were writing about the topic seriously (1970s) people thought the motivation to go to another reactor type was that we'd run out of U235, not that gas turbine generators would come online and wreck steam turbine economics.
Solstinox 6y ago
If you want to work in "the world of atoms" that Peter Thiel likes to refer to, there is a lot of money to be made in dealing with corrosion. In the US, it eats away 200-300 billion every year.
- rsfern 6y ago
  Totally — there’s a NACE report [0] that estimates the cost of corrosion damage and mitigation at 3+% of the global GDP (in 2013 anyway), which is nuts to me. [0] http://impact.nace.org/economic-impact.aspx http://impact.nace.org/economic-impact.aspx
  - benzofuran 6y ago
    Keep in mind the IMPACT report is the cost, not the amount spent on fixes. It's still pretty significant though. There's some internal discussion on updating the report but the arguments over spend vs cost are raging.
  - tsomctl 6y ago
    Oxygen is an extremely nasty, extremely corrosive, extremely toxic gas. It's just that life has evolved to use it, and engineering has evolved to deal with it. Think of how dangerous forest fire is. You have billion dollar companies who's main product (paint) is to prevent the damage from oxygen (PPG, Sherwin-Williams). Walk into any workshop, and the most thing is going to be the oxygen cylinder.
ISL 6y ago
It takes a special kind of scientist to want to create a simultaneous irradiation/corrosion facility. Especially with fluorine salts. I'd love to see all the paperwork and planning that preceded the work :).
- the8472 6y ago
  Looks like "facility" here means another experiment that can be plugged into the end of an existing accelerator beamline, not some purpose-built industrial complex as one might associate with the word. https://sci-hub.tw/10.1016/j.nimb.2018.11.024 https://sci-hub.tw/10.1016/j.nimb.2018.11.024
opwieurposiu 6y ago
Radiation can turn boring old HDPE (milk jug plastic) into amazingly strong PEX. A case where ionizing radiation actually provides super powers. https://en.wikipedia.org/wiki/Cross-linked_polyethylene https://en.wikipedia.org/wiki/Cross-linked_polyethylene

Note that materials and salts like this could be used for Thorium based nuclear energy and of course you get the irradiation for free.

deleted 6y ago
[deleted]
tlb 6y ago
Thorium reactors generate beta particles, gamma rays, and neutrons, not the protons used in the study. They conjecture that neutrons will have a similar effect, but haven't tested it.
- jojobas 6y ago
  It's guaranteed to have a different effect, neutron capture will manifest in different isotopes with different products.
irjustin 6y ago
> Proton irradiation-decelerated intergranular corrosion This is specifically proton irradiation as opposed to neutron. It doesn't appear to come for free.
- rsfern 6y ago
  At the end of the discussion section, there is some evidence presented that this self-healing effect occurs under neutron irradiation as well, though the exact implications for fast reactor materials seem unclear. Makes sense, the basic mechanism seems to be mediated by increased interstitial diffusion. Shouldn’t really matter if it’s protons or neutrons that are generating those interstitials Edit: on re-reading, it doesn’t seem that they’ve actually performed any neutron irradiation experiments
  - benzofuran 6y ago
    Neutron radiation leads to embrittlement in many materials, so the long term effects will have to be considered in addition to short term corrosion rate improvements.
    - rsfern 6y ago
      That’s a really good point, and I agree, but any alloy used for reactor components is going to have to deal with embrittlement one way or another. At the end of the day this is just another potential tool in the alloy design toolbox, and it might or might not turn out to be useful for mitigating corrosion in reactor materials
acidburnNSA 6y ago
Also, nearly identically, in uranium-based molten salt reactors. The safety and sustainability that enticed e.g. Andrew Yang to like thorium are actually coming from low-pressure coolant and the concept of breeding, both of which are possible with thorium or uranium fuel cycles. The thorium itself has nearly nothing to do with either benefit. It's basically a rebranding of non-light water reactor nuclear. Thorium has one major primary physical differentiator, which is that it alone allows breeding with slow neutrons. Uranium needs fast neutrons to breed. Both options have pros and cons that basically wash out.
- PaulHoule 6y ago
  Th and U are soluble in F salts, but Pu isn't. A molten salt reactor that breeds U238 would have to be based on a Cl chemistry which is not so developed. Otherwise you'd get Pu plating out on your heat exchangers, clogging pipes, etc. What makes the LWR non-viable since 1980 or so is not the uranium or even the LWR, but the steam turbine it is attached to. The power density of a steam turbine is at least an order magnitude less than that of the gas turbines that are used to generate electricity today. To a first approximation, the cost of something is proportional to it's volume or mass. As it turns out, even if the heat was free the steam turbine alone attached to an LWR would make the cost of electricity uncompetitive. In fact, this is what mostly killed coal. If nuclear power is going to have any economic impact we have to ditch the steam turbine for a closed-cycle gas turbine and ditch the LWR for something that operates at higher temperature. Unfortunately the last time people were writing about the topic seriously (1970s) people thought the motivation to go to another reactor type was that we'd run out of U235, not that gas turbine generators would come online and wreck steam turbine economics.

Solstinox 6y ago

If you want to work in "the world of atoms" that Peter Thiel likes to refer to, there is a lot of money to be made in dealing with corrosion. In the US, it eats away 200-300 billion every year.

rsfern 6y ago
Totally — there’s a NACE report [0] that estimates the cost of corrosion damage and mitigation at 3+% of the global GDP (in 2013 anyway), which is nuts to me. [0] http://impact.nace.org/economic-impact.aspx http://impact.nace.org/economic-impact.aspx
- benzofuran 6y ago
  Keep in mind the IMPACT report is the cost, not the amount spent on fixes. It's still pretty significant though. There's some internal discussion on updating the report but the arguments over spend vs cost are raging.
- tsomctl 6y ago
  Oxygen is an extremely nasty, extremely corrosive, extremely toxic gas. It's just that life has evolved to use it, and engineering has evolved to deal with it. Think of how dangerous forest fire is. You have billion dollar companies who's main product (paint) is to prevent the damage from oxygen (PPG, Sherwin-Williams). Walk into any workshop, and the most thing is going to be the oxygen cylinder.

ISL 6y ago

It takes a special kind of scientist to want to create a simultaneous irradiation/corrosion facility. Especially with fluorine salts. I'd love to see all the paperwork and planning that preceded the work :).

the8472 6y ago
Looks like "facility" here means another experiment that can be plugged into the end of an existing accelerator beamline, not some purpose-built industrial complex as one might associate with the word. https://sci-hub.tw/10.1016/j.nimb.2018.11.024 https://sci-hub.tw/10.1016/j.nimb.2018.11.024

opwieurposiu 6y ago

Radiation can turn boring old HDPE (milk jug plastic) into amazingly strong PEX. A case where ionizing radiation actually provides super powers. https://en.wikipedia.org/wiki/Cross-linked_polyethylene https://en.wikipedia.org/wiki/Cross-linked_polyethylene