OBSERVATIONS ON USE OF THE J INTEGRAL TO DETERMINE PLANE-STRAIN FRACTURE TOUGHNESS FROM SUBSIZED SPECIMENS OF A TITANIUM 6AL-4V ALLOY

J-integral procedures were used to obtain resistance curves of J versus crack extension from fatigue-precracked specimens of a titanium 6Al-4V alloy. Specimens of various geometries were employed, all in three-point bending. Crack extensions were delineated by heat tinting. The value of the J integral at the initiation of crack extension, J sub Ic, was determined from the resistance curves and compared with a valid K sub Ic value for this material. Comparison was made of the results obtained with the approximation equation J = 2A/Bb to those obtained with the more cumbersome compliance technique in which the analytical plane-stress solutions of Bucci et al. were used. The range of ratios of crack length to specimen width was examined over which J = 2A/Bb holds, as was the decrease in crack extension at the experimental limit load with increase in ratio of specimen thickness to uncracked ligament. Variation in J sub Ic from specimens cut from different positions through the plate thickness was also explored. (Author)

• Corporate Authors:

  Naval Research Laboratory

  4555 Overlook Avenue, SW
  Washington, DC  United States  20375-5320
• Authors:
  • Yoder, G R
  • Griffis, C A
• Publication Date: 1974-9-3

Media Info

• Pagination: 21 p.

Subject/Index Terms

• TRT Terms: Cracking; Fracture mechanics; Fracture properties; Stresses
• Uncontrolled Terms: Crack propagation; Stress intensity factors
• Subject Areas: Marine Transportation; Materials;

Filing Info

• Accession Number: 00084821
• Record Type: Publication
• Source Agency: National Technical Information Service
• Report/Paper Numbers: NRL-7789 Final Rpt.
• Files: TRIS
• Created Date: May 19 1975 12:00AM