Microtopographic Analysis of Part-Through Crack Growth in Alloy 304L Plate-type Tension Specimens

Lloyd, W. R. ; Steffler, E. D. ; Jackson, J. H.

Idaho National Laboratory

关键词: Ineel;    Part-Through Crack Specimen;    Stainless Steel;    Plate-Type Specimen;    54 - Environmental Sciences, 58 - Geosciences Ineel;   

DOI  :  10.2172/911028
RP-ID  :  INEEL/EXT-03-00495
RP-ID  :  DE-AC07-99ID-13727
RP-ID  :  911028

美国|英语

来源: UNT Digital Library

【 摘 要 】

The Idaho National Engineering and Environmental Laboratory (INEEL) used their microtopography analysis method to examine the fracture process in two Type 304 stainless steel, part-through crack, plate-type specimens. The two specimens had different initial defect geometries – one being nearly semicircular and moderately deep, the other being longer and shallower. The microtopographic analysis allowed determination of parameters such as: the crack tip opening displacement at initiation; the crack tip opening angle during ductile tearing; the crack mouth opening at through-thickness penetration; and, the incremental crack front profiles throughout the crack growth process. In essence, these data provide a nearly complete description of the entire ductile fracture process for the two cases examined. We describe the microtopographic analysis procedure as it was applied to these two specimens. Crack growth profiles predicted by the microtopography analysis are compared with those shown by heat tinting of the actual fracture subsurface, showing excellent agreement. Several areas of ductile crack growth theory relevant to the microtopographic method of analysis are discussed, including possible effects on the accuracy of the analyses. The accuracy of the resultant data is reviewed, and found acceptable or better. Areas for additional development of the microtopography method to improve accuracy in three-dimensional ductile fracture analysis are identified.