Slow Crack Growth Behavior and Life/Reliability Analysis of 96 WT % Alumina at Ambient Temperature with Various Specimen/Loading Configurations

By: Nasa, National Aeronautics and Space Adm

Extensive constant stress-rate testing for 96 wt % alumina was conducted in room-temperature distilled water using four different specimen/loading configurations: rectangular beam test specimens under four-point uniaxial flexure, square plate test specimens in ring-on-ring biaxial flexure, square plate test specimens in ball-on-ring biaxial flexure, and dog-boned tensile test specimens in pure tension. The slow crack growth (SCG) parameter n was almost independent of specimen/loading configurations, in either four-point uniaxial flexure, ring-on-ring biaxial flexure, ball-on-ring biaxial flexure, or pure tension, ranging from n = 35 to 47 with an average value of n = 41.1 +/- 4.5. The prediction of fatigue strength/reliability based on the four-point uniaxial flexure data by using the CARES/Life design code as well as a simple PIA model was in good agreement with both the ring-on-ring biaxial and the ball-on-ring biaxial flexure data. A poor prediction using the PIA model was observed for the dog-boned tensile test specimens, presumably due to different flaw population involved in the tensile test specimens.Choi, Sung R. and Powers, Lynn M. and Nemeth, Noel N.Glenn Research CenterCRACK PROPAGATION; DEFECTS; RELIABILITY ANALYSIS; LIFE (DURABILITY); ALUMINUM OXIDES; AMBIENT TEMPERATURE; TENSILE TESTS; RECTANGULAR BEAMS; FLEXING; DISTILLATION

• Format: Paperback
• Language: English
• ISBN: 172375451X
• ISBN13: 9781723754517
• Release Date: January 1
• Publisher: Independently Published
• Length: 30 Pages
• Weight: 0.21 lbs.
• Dimensions: 0.1" x 8.5" x 11.0"