Magnetorheological finishing explained

Magnetorheological finishing (MRF) is a precision surface finishing technology. Optical surfaces are polished in a computer-controlled magnetorheological (MR) finishing slurry. Unlike conventional rigid lap polishing, the MR fluid's shape and stiffness can be magnetically manipulated and controlled in real time. The optic's final surface form and finishing results are predicted through the use of computer algorithms.

In 1999, researchers at the Optical Processing Center of the University of Rochester studied the mechanical and chemical principles of magnetorheological polishing, determined the removal relationship of a series of non-magnetic polishing powders of different hardness on optical glass of different hardness, and studied the polishing area of magnetorheological polishing, analyzed the characteristics of the polishing area of several materials, and introduced the rapid text editor (OED) technology into the Q22 magnetorheological polishing machine, making the MRF technology commercialized.^[1]

Literature

http://pubs.rsc.org/en/content/ebook/978-1-84973-667-1#!divbookcontent W.I. Kordonski (2014). "Magnetorheological Fluid-Based High Precision Finishing Technology." Magnetorheology: Advances and Applications, Norman M. Wereley, Ed., RSC Smart Materials, Cambridge, UK, Chapter 11, 261–277.

DOI:10.1039/9781849737548-00261

http://www.freepatentsonline.com/EP0858381B1.pdf S.D. Jacobs, W.I. Kordonski, I.V. Prokhorov, D. Golini, G.R. Gorodkin, T.D. Strafford (2002). "Deterministic Magnetorheological Finishing." US Patent: US5449313A
http://www.opticsinfobase.org/ao/abstract.cfm?uri=ao-40-1-20 Shorey et al. "Experiments and Observations Regarding the Mechanisms of Glass Removal in Magnetorheological Finishing", abstract and full text (pdf)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-48-13-2585 Chunlin Miao, et al., "Shear stress in magnetorheological finishing for glasses," Applied Optics 48, 2585-2594 (2009)
http://www.opticsinfobase.org/ao/abstract.cfm?URI=ao-49-10-1951 Chunlin Miao, et al., "Process parameter effects on material removal in magnetorheological finishing of borosilicate glass," Applied Optics 49, 1951-1963 (2010)
German Patent: DE69924595T2

Notes and References

Book: Golini, Donald: Kordonski,William I;Dumas,Paul;Hogan,Stephen J. . Magnetorheological finishing (MRF)in commercial precision optics manufacturing . Proc.SPIE Vl.3782.80-91(1999).