Fracture and Fatigue of Diffusion, Explosive, and Roll Bonded Al/Al and Ti/Al Laminates
Abstract
The fracture and fatigue crack propagation characteristics of Al/Al and Ti/Al laminates were evaluated. Seven laminate panels of approximately 12.7 mm (0.50 in.) thickness were fabricated using diffusion, explosive, and roll bonding procedures. Specific alloy systems investigated included: diffusion bonded and roll bonded 7475 Al/1100 explosive bonded and roll bonded 7075 Al/ 7072 Al, and diffusion bonded Ti-6Al-4VAl. A typical laminate consisted of five 2.3 mm (0.090 in.) 7475 Al primary layers interleaved with four 0.13 mm (0.005 in.) 1100 Al secondary layers. It was found that all laminates exhibited substantially higher critical fracture toughness in the crack divider orientation than corresponding baseline, monolithic plate alloys. For example, the Al/Al laminates possessed average toughness values that ranged from 33% to 56% higher than those values for monolithic 7475 Al and 7075 Al plates. The Ti- 6Al-4V/6061 Al panel had a toughness 117% higher than the baseline Ti-6A1-4V plate. Crack divider fatigue crack propagation rates were found to be similar to those rates for the baseline alloy plates. Crack arrest orientation fracture and fatigue propagation tests confirmed these laminates had significant crack arrest capacity. Criteria were outlined for efficient metal/metal laminate design for achieving highly damage tolerant structural materials. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- May 13, 1977
- Accession Number
- ADA040387
Entities
People
- R. D. Goolsby
Organizations
- Vought