Rehbinder effect

{{Short description|Physical effect of surfactants on materials}}

In physics, the Rehbinder effect is the reduction in the hardness and ductility of a material, particularly metals, by a surfactant film.{{Cite journal | last1 = Andrade | first1 = E. N. D. C. | last2 = Randall | first2 = R. F. Y. | last3 = Makin | first3 = M. J. | doi = 10.1088/0370-1301/63/12/304 | title = The Rehbinder Effect | journal = Proceedings of the Physical Society, Section B | volume = 63 | issue = 12 | pages = 990 | year = 1950 |bibcode = 1950PPSB...63..990A | s2cid = 4078138 }} The effect is named for Soviet scientist {{ill|Piotr Aleksandrovich Rehbinder|ru|Ребиндер, Пётр Александрович}},{{cite journal |last1=Rehbinder |first1=Piotr |last2=Logghinov |first2=G. |journal=Proceedings of the USSR Academy of Sciences |date=1941 |title=[Rehbinder and Logghinov] |volume=30 |issue=491 |language=Russian |issn=0002-3264}}{{cite journal |last1=Shchukin |first1=Eugene D. |title=Physical–chemical mechanics in the studies of Peter A. Rehbinder and his school |journal=Colloids and Surfaces A: Physicochemical and Engineering Aspects |date=April 1999 |volume=149 |issue=1–3 |pages=529–537 |doi=10.1016/S0927-7757(98)00607-4 |issn=0927-7757|doi-access=free }} who first described the effect in 1928.{{cite journal |last1=Traskin |first1=Vladimir Yu. |title=Rehbinder Effect in Tectonophysics |journal=Izvestiya, Physics of the Solid Earth |date=2009 |volume=45 |issue=11 |pages=952{{endash}}963 |doi=10.1134/S1069351309110032 |bibcode=2009IzPSE..45..952T |issn=1069-3513}}

A proposed explanation for this effect is the disruption of surface oxide films, and the reduction of surface energy by surfactants.{{cite journal |last1=Chaudhari |first1=Akshay |last2=Soh |first2=Zhi Yuan |last3=Wang |first3=Hao |last4=Kumar |first4=A. Senthil |title=Rehbinder effect in ultraprecision machining of ductile materials |journal=International Journal of Machine Tools and Manufacture |date=2018 |volume=133 |page=47-60 |doi=10.1016/j.ijmachtools.2018.05.009 |s2cid=117157657 |url=https://www.sciencedirect.com/science/article/pii/S0890695518301214|url-access=subscription }}

The effect is of particular importance in machining, as lubricants reduce cutting forces.{{cite journal |last1=Lee |first1=Yan Jin |last2=Wang |first2=Hao |title=Current understanding of surface effects in microcutting |journal=Materials & Design |date=July 2020 |volume=192 |page=108688 |doi=10.1016/j.matdes.2020.108688 |s2cid=216307550 |doi-access=free }}