A study of the transient liquid phase bonding process applied to a Ag/Cu/Ag sandwich joint

Modelling of transient liquid phase bonding in binary systems—A new parametric study

“…Eq. (A.3) is exactly the result proposed by Tuah-Poku et al [15] and Liu et al [7] (whose investigations were restricted to the particular case where c 0 = 0 and liquid and solid densities are equal). Given that the validity of this approximation is limited to applications in which c I ≥ c L c S > c 0 , and given that the exact solution is not very much more complicated, it would be preferable to use Eq.…”

“…The physical description of TLP bonding as a diffusioncontrolled phase change is well-established [4][5][6][7][11][12][13][14][15][16][17][18][19] and simulations made on this basis have been found to agree reasonably well with experimental observations [12,13]. Although the mathematical models used previously differ slightly from each other, there is general agreement on the nature of the underlying physical phenomena.…”

“…The initial half-thickness of the liquid layer at the onset of solidification (s 0 ) may be determined by a simple solute balance, which assumes that none of the MPD enters the solid during dissolution [15]. It is convenient to introduce a system of coordinates in which the origin lies at the centre of the bond-line; the symbol x is used to denote this positional variable, and the position of the inter-phase interface is s(t).…”

“…Certain other formulae for t * have also been proposed [7,15]. It has pre-viously been pointed out [14] that these can contain significant errors, although this covered only fixed values of concentration c 0 , whereas Fig.…”

“…(1)- (6). Some authors [7,15] have presented different formulae. These were derived using expressions that do not constitute an exact solution to the governing equations and, as such, may be considered erroneous.…”