Notch effect and brittle-ductile transition

We present the fresults of the investigation of the effect of notches on the brittle-ductile transition in the process of fracture of structural materials. It is shown that the local elastoplastic state of a material in the vicinity of the notch can be described by using the corresponding stress intensity factorsK _I ^σ , strain intensity factorsK _i ^ε , and strain-energy intensity factorsK _I ^ω . We prove that the factorsK _I ^σ andK _I ^ε are linear functions of the notch radius ρ on the coordinates (wherei=σ or ε) and propose to characterize the brittle-ductile transition in the process of fracture of the material by the slopes of these functions. Bay Zoltan Institute of Logistics and Production Systems, Miskolc-Tapolca, Hungary. Published in Fizyko-Khimichna Mekhanika Materialiv, Vol. 34, No. 5, pp. 27–33, September–October, 1998.