Introduction to the J Integral.

Current research programs center on various analysis concepts of the elastic plastic toughness regime. One of these, the J integral, is a relatively new analytical concept with which little experimental investigation has been attempted to date. Yet the approach appears to offer the prospect of significant near term advances in characterization of the elastic plastic regime. The paper provides an introduction to the J integral in terms for one who is not actively engaged in the field. The description of the J integral includes the advantages of this approach as a failure criterion as well as its limitations. Author