Live observation of materials cracking at multiple length scales

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A novel and unique miniature mechanical testing machine is requested that fits into scanning electron microscopes for the live observation of crack nucleation at nano and microscales. The requested machine will be used to deform and test the high value strategic metal alloys used in nuclear and other energy sectors, as well as the polymers used in transportation industry. It will enable us to study the combined effects of mechanical and thermal loads on materials performance and to study how mechanical properties of materials degrade as a result of the harsh environment that they are exposed to. More than 50% of energy in Ontario, and 15 % nationwide, is being produced through CANada Deuterium Uranium (CANDU) nuclear reactors. These reactors significantly contribute to the production of low-emission energies, helping us address many challenges related to climate change. There has been more than $25B investment to refurbish CANDUs to produce energy until 2064. The lifetime of these reactors is significantly affected by the degradation of the zirconium metal alloys used in the core of reactors. Some examples of such mechanisms include the formation of a brittle phase known as zirconium hydride, cracking, creep, and irradiation embrittlement. Many fundamental questions regarding these degradation mechanisms remain un-answered. For example, the mechanisms that control the formation of cracks at nano and microscales and the interaction of cracks with hydrides or irradiation-induced defects are yet not well-understood. The requested mechanical testing machine will enable us to tackle such long-standing questions. It fits into electron microscopes, allowing us to observe the formation of cracks in metal alloys, and to measure the development of local strain and stresses at multiple length scales. It will be coupled with advanced imaging and diffraction techniques to generate the experimental data required for numerical model development, and hence, it is expected to have significant impact on ensuring the safe and efficient operation of nuclear reactors used both in Canada and around the world. The requested mechanical testing machine will also be used to characterize the performance of the superalloys that have been manufactured by additive manufacturing techniques for the next generation of gas turbines. The aim is to manufacture components that help further reduce carbon emissions while having superior performance. The requested machine will also be used to study deformation and fracture of polymers used in transportation industry for weight reduction.