Expedited Fabrication of Conformal Window for ABL

The manufacture of meter-class windows and mirrors requires extended fabrication periods, often longer than one year. This is because current fabrication techniques entail multiple stages of grinding, lapping, and polishing to achieve high surface finish and dimensional requirements. Our Phase II project will demonstrate innovative ductile mode machining (DMM) process and modeling technology the MDA needs for fast, affordable, high quality meter-class windows and mirrors for the ABL. Our innovative program will: (a) Reduce fabrication times by 50% via reduction/elimination of grinding, lapping and polishing; (b) Achieve higher part quality, (10–50 nanometer RMS surface roughness); (c) Virtually eliminate surface and subsurface flaws; (d) Predict beneficial DMM conditions; and (d) Reduce cost of windows and mirrors. DMM is the key technology, supported by advanced process modeling, which we will use with universities and conformal window fabricator Brashear to demonstrate the proposed production-level benefits for windows and mirrors. Our three-phased disciplined development program will: (a) Complete technology development for production-level DMM; (b) Fabricate a scaled prototype window using DMM; (c) Determine production-level process conditions for SiC mirrors and fabricate via DMM.