Investigation of plastic and slipping regions at the edge of an adhered complete contact of elastically dissimilar materials

Abstract

Slipping and yielding at a sharp edge in an adhered and complete contact problem is studied. Eigenvalue problem is formed and eigen-solutions are obtained. Stress distribution in the vicinity of the sharp edge is analyzed using the singular terms of the stress equations. Generalized stress intensity factors, KI and KII are evaluated using a simple finite element analysis. Von Mises yield criterion is applied to observe the boundary of the plastic region on the contact surface. Ratio of the shear to normal stresses is compared with the coefficient of friction to estimate the slip region. With using those analysis method, analyzed is a contact between a cracked pellet and a cladding tube of a nuclear fuel rod, made of uranium dioxide and zirconium alloy, respectively, as an example problem. Under the average contact stress of 10 MPa, the contact length of 10 mm, and 0.3 ≤ μ ≤ 0.7, the size of the plastic region is found extremely tiny (order of 10-6 mm) in the cladding tube. Whereas, the size of the slip region in the vicinity of the contact edge dramatically changes (order of 1.0 ∼ 10-8 mm). The effect of material dissimilarity is investigated for the condition of xp = xs. The result is displayed in the Dundurs parallelogram domain, (α,β).