Beilby layer

Jewelry Discussion
1

“Beilby layer” is the name applied to the liquid-like layer of
ultramicroscopic depth produced during the polishing of It
may be described as a local fusion at the minute projecting points on
the nearly plane surface and the consequential spreading of a
liquid-like layer over the entire surface. The nature of the polish
layer may be divided into four groups:

(1) The melting point appears too high for the production of a
Beilby layer. The polishing process being merely a fine grinding,
e.g., Diamond (and graphite).

(2) The Beilby layer is amorphous (liquid-like) at the moment of
formation, but immediately recrystallises in the same orientation as
the underlying crystal structure, e.g., Quartz.

(3) In which the Beilby layer recrystallises only on surfaces which
approximate to important crystal planes (as cleavage surfaces and
possible crystal faces), e.g., Calcite and Kyanite.

(4) In which the Beilby layer remains amorphous on all surfaces,
e.g., Spinel and Zircon.

This definition is from the “Winjewel” dictionary:
http://207.141.14.173/winjewel/bDict.htm

Al Heywood

2

As far as I know, the Beilby layer isn’t theory.

Frank Bowden didn’t seem to think so either Bruce! From the site
“Physics in Australia to 1945” at:

http://www.asap.unimelb.edu.au/bsparcs/physics/P000247p.htm

Frank Philip BOWDEN,

Born Hobart 2 May 1903; died Cambridge, England, 3 September 1968.
Education University of Tasmania (B.Sc. 1925, M.Sc. 1927, D.Sc. 1931)
and Gonville & Caius College, Cambridge (Ph.D. 1929), Sc.D. 1938).
Research scholar University of Tasmania 1926. 1851 Exhibition
scholar 1927-28; senior scholar 1929-31. Demonstrator in chemistry,
Cambridge University, 1931-37; lecturer in physical chemistry,
1937-39. Officer-in-charge, Lubricants & Bearings Section, C.S.I.R.,
1939-45. Reader, physical chemistry, Cambridge, 1946-57; physics,
1957-66; professor of surface physics 1966-68. F.R.S. 1948. Rumford
Medal 1956.

These are some of his published works, all relevant to the
discussion (except for the ferret thing).

(With W.G. Beare) Physical properties of surfaces. I. Kinetic
friction. Royal Society of London. Philosophical Transactions., A,
234 (1935), 329-354.

(With K.E.W. Ridler) Physical properties of surfaces. III. The
surface temperature of sliding metals. The temperature of lubricated
surfaces. Proceedings of the Royal Society of London, A, 154 (1936),
640-656.

(With F.H.A. Marshall) The f=FCrther effects of irradiation on the
oestrous cycle of the ferret. Journal of Experimental Zoology, 13
(1936), 383-386.

(With T.P. Hughes) Surface temperature of rubbing solids and the
formation of the Beilby layer. Nature, 139 (1937), 152.

(With T.P. Hughes) The surface temperature of sliding solids and its
influence on surface flow and wear. International Association for

(With T.P. Hughes) Physical properties of surfaces. IV. Polishing,
surface flow and the formation of the Beilby layer. Proceedings of
the Royal Society of London, A, 160 (1937), 575-587.

The polishing of solids and the mechanism of sliding on ice and
snow. Society of Chemical Industry of Victoria. Proceedings., 40
(1940), 240-250.

(With D. Tabor) Mechanism of metallic friction. Nature, 150 (1942),
197-199.

The physics of rubbing surfaces. Royal Society of New South Wales.
Journal and Proceedings., 78 (1944), 187-219.

(With J.N. Gregory and D. Tabor) Lubrication of metal surfaces by
fatty acids. Nature, 156 (1945), 97-101.

Al Heywood