Evaluation of smooth and notched specimen fatigue behavior of Al-2.6Li-0.09Zr

Smooth and notched specimen fatigue tests were conducted on an experimental, ternary aluminum-lithium-zirconium alloy, to evaluate the influence of aging time, extrusion geometry, specimen orientation, and extrusion temperature on fatigue behavior. Round-rod material was extruded at 500°F (260°C) and 800°F (427°C), whereas a flat-bar product was extruded at 800°F (427°C). Completely reversed strain-controlled tests were conducted at a constant strain rate for round axial specimens and flat axial specimens. Cyclic data were recorded in logarithmic increments of the specimen life, and corresponding stress-strain hysteresis loops were generated. Smooth and notched cylindrical specimens machined from the material extruded at 800°F (427°C) were tested under stress control.