Polishing of X-Ray Optics

Manufacturing grazing incidence x-ray mirrors costs between $4 to $6 million per square meter of optical surface area.nbsp; To reduce the cost of making x-ray mirrors, NASA is seeking manufacturing solutions to aid in cost reduction factors of 5 to 50 times.nbsp; One cost driver is the mandrel-based polishing process that impacts both the inside and outside surfaces of an X-ray mirror shell.nbsp; Current shells are created through a replication process utilizing an aluminum mandrel.nbsp; OptiPro is proposing to enhance process solutions to reduce the cost required for polishing both the mandrel and the outside shell surface by maintaining a constant force during polishing, developing new polishing tools, and optimizing the polishing algorithm.nbsp; The target platform for these improvements will be on OptiPro#39;s bridge polishing platform that has a rotary A-axis to spin the part and a combination polishing head that can handle a range of polishing tools while making it easier to rapidly switch between tools.nbsp; These improvements will be directly applicable to the polishing being done at Marshall Space Flight Center on various equipment including OptiPro#39;s 6-axis UltraForm Finishing platform. OptiPro Systems will focus on the process evaluation and the interface between the polisher and metrology platform to provide a cost effective deterministic solution.nbsp; A new force-measurement system will also be evaluated for its potential to provide in-situ process feedback during polishing.nbsp; New polishing tools will be designed, built, and tested along with the pellet tool developed at MSFC and other commercially available polishing tools.nbsp; Algorithm changes will be required for polishing the surfaces of the x-ray mirror mandrel and shells and will be demonstrated on a surrogate aluminum mandrel.nbsp; The results of this Phase I effort will enhance the fabrication at MSFC and provide the concept design requirements of a meter class finishing platform which could be built in a Phase II effort.