Proton Irradiation Effects on the Physio-Mechanical Properties and Microstructure of Cold-Worked Molybdenum

High temperature refractory materials and alloys including Mo and TZM have been considered and studied to assess their applicability in fusion reactor applications in addition to spallation targets in particle accelerators. The impacts of neutron, proton and ion irradiation on the properties and microstructure of pure Mo and its combination TZM have been evaluated through illumination damage studies. Cold-worked molybdenum (CW half), described by a microstructure comprising of non-consistently extended grains, has been considered for use in the Large Hadron Collider 7 TeV shaft halo cleaning framework has incited the present investigation. To assess the degradation of key physio-mechanical properties of the cold-worked structure following protracted exposure to proton irradiation as well as the impact of the irradiation temperature on the degradation irradiations with 200 MeV protons at 960°C to fluencies $\sim 2 \times 10^{21}$ p/cm$^{2}$ and with 28 MeV at below 600°C to fluency of $\sim 6 \times 10^{20}$ p/cm$^{2}$ were performed at Brookhaven National Laboratory. High energy X-rays at the NSLS and NSLS II synchrotrons were utilized in the post-irradiation evaluation (PIE) to assess the evolution of the microstructure. It was revealed that the cold-worked Mo and in agreement with neutron irradiation studies at high temperatures, suffers serious reduction in tensile strength due to the evolution of defects into dislocation networks. Further, irradiation at temperatures near the full re-crystallization temperature of the cold-worked structure removes the texture of the microstructure induced by cold working.