STRESS INTENSITY FACTORS FOR A CRACK IN PLANAR DISKING

Disking is a relatively new manufacturing process for cutting/slicing brittle plates and rods. In the planar disking configuration, a pre-cr acked plate is placed against an elastic plate and the two are squeeze d together by fluid pressure. At a critical pressure the crack runs ac ross the thickness of the brittle plate producing a clean cut. In this paper a fracture criterion is developed for the process using linear elastic fracture mechanics. The geometry of the process is modeled her e as two perfectly bonded, infinite elastic layers with a crack perpen dicular to the interface. The problem is formulated in terms of a sing ular integral equation with the derivative of the crack surface displa cement (dislocation density) as the unknown function. Numerical quadra ture is used to determine the stress intensity factors as a function o f the parameters of the problem.