Thermophysical and mechanical characterization of advanced materials for the LHC collimation system

The aim of the thesis is to describe the methods employed for the thermo-physical and mechanical characterization and to show the results of the campaign conducted over two ceramic matrix composites, CFC FS140® and MG-6403-Fc, which are candidates as jaws materials in the LHC collimation system. The work was conducted at the European Organization for Nuclear Research (CERN, Geneva), in the framework of the R&D activities done by the EN department. The goal of this project is to develop and characterize materials able to withstand highly energetic particles interactions to protect the accelerator’s components and to clean the beam. In the first part of the thesis, the instruments employed for the thermal and mechanical analysis are studied, from the mathematical models to the standard test methods. These instruments are: horizontal push-rod dilatometer, differential scanning calorimeter, laser flash apparatus and universal testing machine. The results of the analysis show lower thermal and electrical conductivities of the CFC chosen, with respect with the one currently in use. The MoGR grade is in line with the previously developed ones, suggesting further improvement in the manufacturing process. The status of the collimators materials’ development process after these characterization, sees the MoGR as baseline material for the primary and secondary collimators and the CFC to produce spares. Carrying out the campaign had been of paramount importance in understanding the physical principles and the technology behind the techniques, and to acquire experience in the thermo-physical and mechanical test engineering.