Acidic magnetorheological finishing of infrared polycrystalline materials

Journal Article · Wed Oct 12 00:00:00 EDT 2016 · Applied Optics

DOI:https://doi.org/10.1364/AO.55.008448· OSTI ID:1328775

Salzman, S. ^[1]; Romanofsky, H. J. ^[2]; West, G. ^[2]; Marshall, K. L. ^[2]; Jacobs, S. D. ^[2]; Lambropoulos, J. C. ^[2]

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1. Univ. of Rochester, Rochester, NY (United States); Laboratory for Laser Energetics, University of Rochester, Rochester, NY
2. Univ. of Rochester, Rochester, NY (United States)

Here, chemical-vapor–deposited (CVD) ZnS is an example of a polycrystalline material that is difficult to polish smoothly via the magnetorheological–finishing (MRF) technique. When MRF-polished, the internal infrastructure of the material tends to manifest on the surface as millimeter-sized “pebbles,” and the surface roughness observed is considerably high. The fluid’s parameters important to developing a magnetorheological (MR) fluid that is capable of polishing CVD ZnS smoothly were previously discussed and presented. These parameters were acidic pH (~4.5) and low viscosity (~47 cP). MRF with such a unique MR fluid was shown to reduce surface artifacts in the form of pebbles; however, surface microroughness was still relatively high because of the absence of a polishing abrasive in the formulation. In this study, we examine the effect of two polishing abrasives—alumina and nanodiamond—on the surface finish of several CVD ZnS substrates, and on other important IR polycrystalline materials that were finished with acidic MR fluids containing these two polishing abrasives. Surface microroughness results obtained were as low as ~28 nm peak-to-valley and ~6-nm root mean square.

• Research Organization: Univ. of Rochester, Rochester, NY (United States). Lab. for Laser Energetics
• Sponsoring Organization: USDOE National Nuclear Security Administration (NNSA)
• Grant/Contract Number: NA0001944
• OSTI ID: 1328775
• Alternate ID(s): OSTI ID: 1328810
• Journal Information: Applied Optics, Journal Name: Applied Optics Journal Issue: 30 Vol. 55; ISSN 0003-6935; ISSN APOPAI
• Publisher: Optical Society of America (OSA)
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
optical fabrication
optics at surfaces
polishing
roughness