Convex interfacial joints with least stress singularities in dissimilar materials

An integrated experimental and numerical investigation is employed to evaluate a new axisymmetric convex joint for the least free-edge stress singularity. Quasi-static tension and dynamic tension experiments of both straight and convex bi-material joints are conducted. Experimental results show that the convex joint yields an increase in final failure strength (up to 22%) and a reduction in material volume (at least 18%), compared to the traditional straight-edged joint. Finite element results indicate that the new axisymmetric convex interfacial joint is effective in removing the stress singularity at the bi-material edge and consequently, a relatively uniform interfacial stress distribution is achieved. The uniform stress distribution leads to more reasonable interfacial strength measurements and higher tensile strengths of dissimilar material joints.

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