Nonlinear Behavior of Low-Plastic Structures

Abstract

Structural-inhomogeneous materials like artificial graphite, ceramics of some sorts, cast iron, are often used for structural members subjected to intensive thermal loading that leads to considerable thermal stresses and hence to low-cycle fatigue at repeated loading Experience reveals that accuracy of the known mathematical models is insufficient for lifetime predictions of structural fracture under such conditions. A version of a structural model is proposed for the description of stress-strain behavior of such materials. Adequacy of the model has been confirmed by results of tests carried out for various loading programs.

Palstic of low-plastic materials are often insufficient to prevent crack forming. In thermostressed structures it often leads to crack mesh formation and growth. A method fo analyzing the crack kinetic is suggested.