Nondestructive characterization of the mechanical strength of diffusion bonds. I. Experimental results

Bond Strength Evaluation in Dissimilar Materials

“…al. (4,5). A saw slot was then introduced above the bond line to simulate a perfect reflector against which the bond signal could be deconvolved in the frequency domain.…”

“…Since the kinetics of diffusion bonding plays an important role in understanding the resulting NDE and mechanical behavior, work was reinitiated on Cu-Cu diffusion bonds at higher pressure than before (4,5) to gain insight into the kinetics of the diffusion bonding process. The pressure chosen for this work is 18.5 MPa which is close to that for the Cu-Ni study and significantly higher than the pressure of 13.3 MPa used by Palmer et.…”

“…al. on Cu-Cu diffusion bonds (4,5). By varying the time and temperature used for diffusion bonding at a constant pressure of 13.3 MPa, a wide range of bond qualities were achieved.…”

“…Although modelling of the diffusion bonding process has been done to predict the bonding parameters needed to achieve parent metal mechanical properties (1,2), the possibility still exists that defects will be present in the bonded plane. There are three classes of defects that can be formed, with voids being the most common and heavily studied ones (3)(4)(5)(6)(7)(8). Contamination of the bond line is a serious defect and the effect on NDE interrogation has been discussed previously by the authors (8) and others (3).…”

Nondestructive Characterization and Bond Strength of Solid-Solid Bonds

“…Copper was bonded to copper [3,4] under a flowing hydrogen atmosphere and uniform pressure over a range of temperatures and times to achieve a homogeneaus distribution of the metallically bonded areas . The bond interfaces were characterized by means of acoustic pulse-echo measurements using broadband focused transducers and by a determination of the bond strength in a tensile test.…”