21 Result(s)

Article

Fatigue Crack Initiation In WASPALOY at 20 °C

In two WASPALOY specimens, the orientations of grains that initiated fatigue cracks and adjacent ograins were measured using electron backscattered diffraction patterns (EBSP). Crystallographic relationships w...

D. L. Davidson, R. G. Tryon, M. Oja… in Metallurgical and Materials Transactions A (2007)

Article

Microstructural and fracture characterization of Nb-Cr-Ti mechanically alloyed materials

Three materials containing Nb, Cr, and Ti were fabricated by consolidating powders made by mechanical alloying. The Nb/Ti ratio was maintained at about 1.3 and Cr was increased to form the intermetallic Cr₂Nb. X-...

D. L. Davidson, K. S. Chan in Metallurgical and Materials Transactions A (2002)

Article

Dislocation structures in a deformed Nb-Cr-Ti solid solution alloy

D. L. Davidson, P. J. Maziasz, J. W. Jones in Metallurgical and Materials Transactions A (2001)

Article

Fatigue and fracture toughness of a Nb-Ti-Cr-Al-X single-phase alloy at ambient temperature

The fatigue and fracture resistance of a commercially made, single-phase Nb-base alloy with 35 at. pct Ti, 5 at. pct Cr, 6 at. pct Al, and several elements to increase solid solution strengthening have been in...

D. L. Davidson, K. S. Chan, R. Loloee… in Metallurgical and Materials Transactions A (2000)

Article

The fatigue and fracture resistance of a Nb-Cr-Ti-Al alloy

The microstructure, fatigue, and fracture behaviors of a cast and heat-treated Nb-Cr-Ti-Al alloy were investigated. The microstructure of the cast alloy was manipulated by annealing at a temperature ranging fr...

D. L. Davidson, K. S. Chan in Metallurgical and Materials Transactions A (1999)

Article

Fracture toughness and fatigue crack growth in rapidly quenched Nb-Cr-Ti In situ composites

In situ composites based on the Nb-Cr-Ti ternary system were processed by rapid solidification in order to reduce the size of the reinforcing intermetallic phase. Two-phase microstructures with s...

K. S. Chan, D. L. Davidson, D. L. Anton in Metallurgical and Materials Transactions A (1997)

Article

The effects on fracture toughness of ductile-phase composition and morphology in Nb-Cr-Ti and Nb-Siin situ composites

Niobium-chromium alloys, both single and two phase, were alloyed with titanium in order to enhance fracture toughness and fatigue crack growth resistance. The selection of titanium as an alloying element and t...

D. L. Davidson, K. S. Chan, D. L. Anton in Metallurgical and Materials Transactions A (1996)

Article

Cu-bearing high-strength low-alloy steels: The influence of microstructure on the initiation and growth of small fatigue cracks

The fatigue characteristics of a Cu-bearing high-strength low-alloy (HSLA) steel were investigated in air, relative humidity ≈50 pct, as a function of microstructure, which was altered by heat treatments and w...

D. L. Davidson, K. S. Chan, R. C. McClung in Metallurgical and Materials Transactions A (1996)

Article

The crack-tip mechanics and growth rates of small fatigue cracks in ASTROLOY

The micromechanics of naturally initiated small fatigue cracks in coarse- and fine-grained nickelbased ASTROLOY have been studied at ambient and elevated temperature using a cyclic loading stage for the scanni...

D. L. Davidson, S. J. Hudak in Metallurgical and Materials Transactions A (1995)

Article

Fatigue crack growth through the lamellar microstructure of an alloy based on TiAl at 25 °C and 800 °C

Fatigue cracks were grown at 25 °C and 800 °C in a titanium aluminide alloy heat-treated to give a γ+ α₂ lamellar microstructure. These lamellae, having widths of =0.5 to 2 μm, were in colonies approximately 1.2 ...

D. L. Davidson, J. B. Campbell in Metallurgical Transactions A (1993)

Article

The micromechanics of fatigue crack growth at 25 °C in Ti-6Al-4V reinforced with SCS-6 fibers

Micromechanics parameters for fatigue cracks growing perpendicular to fibers were measured for the center-notched specimen geometry. Fiber displacements, measured through small port holes in the matrix made by...

D. L. Davidson in Metallurgical Transactions A (1992)

Article

The initiation and growth of fatigue cracks in a titanium aluminide alloy

The micromechanics of small, naturally initiated fatigue cracks and large through-thickness fatigue cracks have been studied in the titanium aluminide alloy Super Alpha 2. The microstructure investigated had e...

D. L. Davidson, J. B. Campbell, R. A. Page in Metallurgical Transactions A (1991)

Article

Effects of interfacial strength on fatigue crack growth in a fiberreinforced Ti-alloy composite

The fatigue crack growth behavior of a Ti-6A1-4V composite with boron fibers was previously studied in the as-received and thermally exposed conditions. Fracture strengths of the composite, fiber, and interfac...

K. S. Chan, D. L. Davidson in Metallurgical Transactions A (1990)

Article

Micromechanics and fatigue crack growth in an alumina-fiber-reinforced magnesium alloy composite

A study has been made of fatigue crack growth through the magnesium alloy ZE41A and a composite of this alloy reinforced with alumina fibers. Crack growth rates were measured and failure mechanisms characteriz...

D. L. Davidson, K. S. Chan, A. McMinn, G. R. Leverant in Metallurgical Transactions A (1989)

Article

Fracture characteristics of Al-4 pct Mg mechanically alloyed with SiC

Subcritical crack growth and rapid fracture of the mechanically alloyed aluminum alloy IN-9052* reinforced with SiC particles have been investigated. Fatigue crack growth rates for the composite exceed those o...

D. L. Davidson in Metallurgical Transactions A (1987)

Article

Fatigue crack growth mechanics for Ti-6Al-4V (RA) in vacuum and humid air

The effects of environment and cyclic stress intensity factor on crack opening displacement and crack tip strain have been measured, and discontinuous crack growth has been observed directly under high resolut...

D. L. Davidson, J. Lankford in Metallurgical Transactions A (1984)

Article

Flow localization accompanying the intergranular fracture of Ni₃Al

E. M. Schulson, D. L. Davidson, D. Viens in Metallurgical Transactions A (1983)

Article

Wear debris due to mode II opening of mode I fatigue cracks in an aluminum alloy

J. Lankford, D. L. Davidson in Metallurgical Transactions A (1983)

Article

Wear Debris Due to Mode II Opening of Mode I Fatigue Cracks in an Aluminum Alloy

J. Lankford, D. L. Davidson in Metallurgical Transactions A (1983)

Article

Titanium alloy fatigue fracture facet investigation by selected area electron channeling

Flat regions (facets) found on fracture surfaces caused by initiation and propagation of fatigue cracks through the titanium alloys IMI-685 tested with and without a 5 min load dwell and Ti-11 have been examin...

D. L. Davidson, D. Eylon in Metallurgical Transactions A (1980)