Mechanical and substructural response of incipiently spalled 316L stainless steel.

Conference · Thu Jan 01 04:00:00 EST 2004

OSTI ID:977828

Gray, III, G T ^[1]; Bourne, N K

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1. George T.

316L SS samples were shock prestrained to a peak stress of 6.6 GPa using a 0.75 {mu}sec pulse duration square-topped shock profile and 'soft' recovered while a second sample was similarly shock loaded, without spall momentum trapping, leading to incipient spall damage. Shock prestraining and 'soft' shock recovery to 6.6 GPa led to an increase in the post-shock flow strength of 316L SS by {approx}100 MPa over the starting material while the reload yield strength of the incipiently spall damaged sample increased by {approx}200 MPa. In this paper the sequential processes of defect generation and damage operative during the shock prestraining, spallation, and reloading of incipiently spalled 316L SS is presented. The influence of shock prestraining, using both triangular-wave loading, via both direct HE and triangular-wave pulses on a gas launcher, as well as 'square-topped' shock prestaining via conventional flyer-plate impact, is crucial to understanding the shock hardening and spallation responses of materials(Gray III, et al. [2003]). The development of predictive constitutive models to describe the mechanical response of incipiently damaged metals and alloys requires an understanding of the defect generation and storage due to shock hardening as well as the additional plasticity and damage evolution during spallation. In this paper the influence of shock-wave prestraining on the process of shock hardening and thereafterthe hardeningand damage evolution accompanying incipient spallation in 316L stainless steel (316L SS) on post-shock constitutive behavior is examined using 'soft' recovery techniques and mechanical behavior measurements.

• Research Organization: Los Alamos National Laboratory
• Sponsoring Organization: DOE
• OSTI ID: 977828
• Report Number(s): LA-UR-04-5889
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALLOYS
DEFECTS
HARDENING
PLASTICITY
SPALLATION
STAINLESS STEELS
STORAGE
TRAPPING
YIELD STRENGTH