A New Test Method for the Measurement of Normal-Shear Bonding Strength at Bi-Material Interface

Abstract

This article presents a new test method, including specimen design, test procedure, and calculation algorithm, for more accurate and complete characterization of bonding strength property of bi-material interfaces. With the proposed method, the stress singularity at the free edge of the bi-material interface is effectively eliminated and the same specimen design can be used for tension, torsion, or combined tension-torsion tests. An iterative algorithm for computing the normal-shear bonding strength envelope from the test results is also developed. As an example, the epoxy-aluminum interface strength envelope is determined by the proposed test method.

Keywords:

• interface mechanics
• interface strength
• stress singularity
• bonding strength envelope
• finite element analysis