ABSTRACT

Interface fracture toughness of bulk bimaterials has been evaluated

on the basis of the fracture mechanics concept (described in

Chapter 2), where the conventional experimental methods have

been established at the practical level in laboratories (e.g., Rice,

1988; Hutchinson and Suo, 1992; Evans and Dalgleish, 1992).

But evaluating the interface toughness between submicron-or

nanometer-thick films and between the films and the substrate

presents difficulties because the fabricating and loading of such

small specimens is restrictive. Although many testing techniques

have been proposed (e.g., Evans et al., 1999; Volinsky et al., 2002;

Nied, 2003; Thouless, 1994; Lane, 2003), we do not have a universal

method yet. This section briefly reviews the proposed methods.

Table 5.1 summarizes the advantages and disadvantages of each

from the standpoint of the applicability of fracture mechanics and

the feasibility of sample preparation and handling.