Mark Daymond, NSERC Industrial Research Chair in Nuclear Materials at Queen’s University, beside the accelerator that is the centrepiece of a new materials testing laboratory. Photo credit: Bernard Clark
“Protons do a lot,” says Mark Daymond, pointing to a container of hydrogen the size of a coffee thermos that will feed protons into an accelerator the size of a school bus. These protons, Daymond says, will do even more by making it possible to test materials that will sit inside a nuclear reactor without having to go to the trouble of putting them inside a reactor.
Daymond, who holds the NSERC Industrial Research Chair in Nuclear Materials at Queen’s University, explains just how much trouble that can be. Most nuclear reactors are dedicated to the task of producing heat to generate electricity, which means their operational parameters do not vary. Attempts to study how materials respond to conditions inside the reactor can therefore only take place within those parameters. “You’re very limited in the kinds of tests you can do,” Daymond says. “For instance, it would be difficult to adjust the stress or the temperature or the flux of particles.”
Above all, anything you put into a reactor will be highly radioactive when you take it out to learn more about how it held up under these conditions. That makes every step of the analysis much more demanding and expensive, as samples must be handled remotely in shielded “hot cells.”
In the face of such problems, Daymond and his colleagues at the Queen’s Nuclear Materials Research Group have spent the past few years developing the Reactor Materials Testing Laboratory (RMTL), which will make the task of assessing such materials simpler and safer. The centrepiece of this facility, which is located in an industrial park at the north end of Kingston, Ont., is a linear accelerator that can deliver beams of protons with energies up to 12 MeV. When those beams are aimed at sample materials such as the zirconium alloys, which are used in the many pipes and tubes that populate a reactor interior, the result will effectively simulate the radiation effects found in that environment. However, the samples themselves will not be rendered significantly radioactive, which means the RMTL has no need for hot cells or other cumbersome infrastructure for handling hazardous components. Beyond safety and convenience, Daymond is looking forward to the lab’s ability to conduct much more varied and revealing tests. “You can control your radiation very carefully,” he says. “You can pick the energy of your particles and the number of particles — you can dial your flux, essentially. You can control your environment very easily, including stress, temperature or corrosion. And the overall level of radiation can be much lower.”
Queen’s officially opened the RMTL in September, acknowledging a $7 million grant from the Canada Foundation for Innovation, a matching $7 million from the Ontario government and additional support from the university and High Voltage Engineering Europa, the Dutch-based manufacturer of the linear accelerator.