Crack Extension in Several High-Strength Steels Loaded in 3.5% Sodium Chloride Solution,
Abstract
The morphology of crack growth was determined on precracked, notched bend specimens of 300M, H11, Maraging 250, 4330V, 9Ni-4Co-0.30C, and 9Ni-4Co-0. 45C (martensitic and bainitic) steels four-point loaded in 3.5% sodium chloride solution. Crack extension from the tip of the fatigue precrack was either by a single crack that propagated along the fatigue crack plane (Type 1 cracking) or by two divergent cracks that propagated at an angle to the fatigue crack plane (Type 2 cracking). The 4330V, 9Ni-4Co-0.30C, and 9Ni-4Co-4.45C (bainitic) showed either Type 1 or Type 2 cracking, depending on the initial stress- intensity level K sub Ii. The remaining steels exhibited only Type 1 cracking. The state of stress had a significant effect on the morphology of Type 2 cracks. The morphology suggests that Type 2 cracking is a result of environmental cracking along crack-tip plastic zones. The influence of yield strength on K sub ISCC can be described by an empirical expression. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1967
- Accession Number
- AD0685377
Entities
People
- Clive S. Carter
Organizations
- Boeing Commercial Airplanes