Numéro
J. Phys. Colloques
Volume 49, Numéro C5, Octobre 1988
Interface Science and Engineering '87
An International Conference on the Structure and Properties of Internal Interfaces
Page(s) C5-707 - C5-717
DOI https://doi.org/10.1051/jphyscol:1988593
Interface Science and Engineering '87
An International Conference on the Structure and Properties of Internal Interfaces

J. Phys. Colloques 49 (1988) C5-707-C5-717

DOI: 10.1051/jphyscol:1988593

SPECIAL MECHANICAL PROPERTIES OF VERY THIN FILMS

T. TSAKALAKOS

Dept. of Mechanics and Materials Science, College of Engineering, Rutgers University, PO Box 909, Piscataway, NJ 08855-0909, U.S.A.


Abstract
The mechanical properties of ultrathin layered films are presented. An enhanced modulus effect has been observed in several composition modulated thin film systems containing short wavelength modulations .8-10nm. The foils were produced by vapor deposition using two or three source evaporator. As compared with homogeneous foils of the same average composition, the modulated foils exhibited an appreciable increase (up to 300%) in modulus. The dependence of various moduli on the modulation parameters (wavelength, composition and amplitude) are described. The plastic behavior, breaking and microhardness of these foils are also presented as a function of the modulation parameters. Current theories based on electronic and strain effects on the elastic constants of metals are also presented to explain the origin of the supermodulus effect.