Science of Finishing of Novel Optical Materials

Tayyab Suratwala | 17-ERD-005


Complex chemical and mechanical interactions occur during optical fabrication, including grinding, polishing, and cleaning. These interactions make it challenging, time consuming, and costly to develop new finishing processes, especially for new optical materials. Predictive models to guide and reduce development time for a new finishing process are needed.

Our research established an improved scientific understanding of the phenomena that govern optical fabrication processes leading to quantitative, predictive models of important optical fabrication metrics (sub-surface mechanical damage, surface roughness, material removal rate, and chemical etching) resulting from both grinding and polishing for a broad range of optical materials. We conducted systematic, controlled experiments on a variety of optical materials (glasses, single crystals, glass ceramics, as well as oxides and non-oxides) with a broad range of material properties (hardness, modulus, chemical reactivity, etc.) and combined that information with newly developed or extended chemical and mechanical models. Our predictive models reduce development time, improve optic specifications, and increase yield of optical finishing processes used to make optics for high energy and power laser systems.

Impact on Mission

Our work supports Lawrence Livermore National Laboratory's core competencies in lasers and optical science and technology. Our results advance the Laboratory's capabilities to make optics for laser systems used in research critical to Livermore's missions including stockpile stewardship, laser-based directed energy, and optical technologies for the Department of Defense.

Publications, Presentations, Etc.

Shen, N., et al. 2018. "Nanoplastic Removal Function and the Mechanical Nature of Colloidal Silica Slurry Polishing." Journal of the American Ceramic Society 102 3141–3151 (2018). LLNL-JRNL-932856.

––– . "AFM Nanoscratching of Optical Materials Near the Elastic-Plastic Load Boundary to Mimic the Mechanics of Polishing Particles." Glass & Optical Materials Division 2018, San Antonio, TX, May 2018. LLNL-PRES-751422.

Suratwala, T., et al. 2018. "Influence of Partial Charge Model for Predicting Material Removal Rate During Chemical Polishing." Journal of the American Ceramic Society . 102 (4): 1566–1578. LLNL-JRNL-746065.

––– . 2018. "Predictive Models for Grinding & Polishing of Various Optical Materials." Glass & Optical Materials Division 2018, San Antonio, TX, May 2018. LLNL-PRES-955225.

––– . 2019. "Sub-Surface Mechanical Damage Correlations After Grinding of Various Optical Materials." Optical Engineering 58(9) 092604 (2019). LLNL-JRNL-765440.

––– . 2019. "Towards Predicting Removal Rate and Roughness During Grinding of Optical Materials." Applied Optics 58(10) 2490-99 (2019). LLNL-JRNL-972565.

––– . 2019. "Connection Between Indentation Fracture and Grinding Behavior in Various Optical Materials." International Congress on Glass 2019, Boston, MA, June 2019. LLNL-PRES-941792.

––– . 2019. "Predictive Models for Grinding & Polishing Various Optical Materials." Optical Fabrication & Testing 2019, Washington, DC, June 2019. LLNL-PRES-969326.

––– . 2019. "Lateral Cracks During Sliding Indentation on Various Optical Materials." Journal of the American Ceramic Society early view doi: 10.1111/jace.16787 (2019). LLNL-JRNL-781757.