Silicon Carbide Grid Fabrication and Vibration Qualification

Single crystal silicon carbide has properties useful to a wide variety of NASA applications, such as X-ray and EUV filters, charge particle filtering, transducers, and ion propulsion. Compared with other commonly used materials, SiC has higher strength, lower weight, higher X-ray transparency, higher stiffness, higher thermal conductivity, lower ion erosion, and higher temperature capability.PhotonFoils will produce prototype single crystal silicon carbide grids of a size and geometry suitable for planned X-ray microcalorimeters, namely X-IFU and LXM. Smaller grids will also be prepared for statistical pressure strength characterization, and for vibration testing to the NASA GEVS acceptance and qualification levels. Phase I will prepare an 88mm grid per the X-IFU TF4 88mm design rules, while Phase II will prepare 100mm and 126mm grids suitable for the X-IFU TF5 filter and the LXM DMS filter, respectively. Phase II will prepare 2-Level LXM grids analogous to the 2-Level silicon grids used for SXS. Phase II will perform GEVS vibration testing on large filters in vacuum, with geometries and sizes relevant to X-IFU and LXM launch requirements.The proposed grids improve the durability, transmittance, and thermal uniformity of microcalorimeter filters and cooled detector blocking filters. They address identified technical deficiencies and risk items for X-IFU and LXM, namely excess power consumption and fragility.The process used to make the grids can also be tailored to creating large area single crystal SiC membranes, with terrestrial applications such as low-scatter X-ray windows, instrumented X-ray windows, high temperature transducers, and high beam power components.