Fellow engineer, Westinghouse Research and Development Center, Pittsburgh, PA
Professor, The University of Tennessee, TN
Pages: 25 Published: Jan 1988
The effects of monotonic and cyclic prestrain on fracture toughness properties of 4340 steel, 4335 steel, and 316 stainless steel were investigated. Monotonic prestrain lowered the toughness levels of the JR-curves and J–T diagrams for these three steels, relative to the virgin material. While cyclic prestrain increased the JR and J–T toughness of 4340 and 4335 steels, it decreased that of 316 stainless steel. The effects of monotonic and cyclic prestrain on JR and J–T curves can be rationalized by material strength. Furthermore, the influence of cyclic prestrain was attributed to the cyclic softening or cyclic hardening characteristics of the virgin material. The transition behavior of the 4340 steel was also altered by monotonic and cyclic prestrain. Moreover, material strength appears to provide a rationale to account for the effects of prestrain history on the transition behavior.
prestrain, load, history, monotonic, cyclic, fracture toughness, steel, J, R, curves, J-T diagrams, material strength, cyclic softening, cyclic hardening, transition behavior, FATT (fracture appearance transition temperature), charpy impact, tensile, upper shelf
Paper ID: STP23266S