IJPAM: Volume 49, No. 1 (2008)

FLUID FLOW INSTABILITY AND MICROSTRUCTURE
EVOLUTION IN THE INCLINED LASER PROCESSING
OF METAL SURFACE COMPRISING IMPURITIES

S. Lugomer$^1$, A. Maksimovic$^2$, G. Peto$^3$, A. Karacs$^4$, A.L. Frenkel$^5$
$^{1,2}$Material Physics Department
``Rudjer Boškovic" Institute
Bijenicka, c. 54, Zagreb, 10001, CROATIA
$^1$e-mail: lugomer@irb.hr
$^2$e-mail: maks@irb.hr
$^{3,4}$Research Institute for Technical Physics and Material Sciences
Hungarian Academy of Sciences
P.O. Box 49, Budapest, H-1525, HUNGARY
$^3$e-mail: peto@mfa.kfki.hu
$^4$e-mail: karacs@mfa.kfki.hu
$^5$Department of Mathematics
University of Alabama
Tuscaloosa, Alabama, 35487-0350, USA
e-mail: frenkel@hotmail.com


Abstract.We have shown that laser surface processing under an angle generates surface morphology which comprises localized structures analogous to gravitationally caused nonlinear instabilities on the inclined plate. The presence of the low and the high melting (boiling) point metal and nonmetal impurities causes instability evolution at the rate much higher than on the pure metal. The fluid surface dynamics influenced by impurities causes formation of irregular long-range structures in the peripheral regions, and irregular short range ones in the central regions of the spot. Thus, chaotic dynamics appears in the whole interaction space, indicating the loss of memory of the initial conditions.

Received: July 24, 2008

AMS Subject Classification: 76-05, 76D05, 76E30, 76A20

Key Words and Phrases: experimental work, Navier-Stokes equation, nonlinear effects, thin fluid films

Source: International Journal of Pure and Applied Mathematics
ISSN: 1311-8080
Year: 2008
Volume: 49
Issue: 1