Mechanisms influencing the plane-strain fracture toughness behavior of commercial aluminum-lithium alloys at cryogenic temperatures are investigated as a function of microstructure and plate orientation. It is confirmed that certain alloys show a marked increase in tensile ductility and toughness with decrease in temperature, although such behavior is not found in the short-transverse orientati...

Surface acoustic wave (SAW) velocity spectroscopy has been long considered to be one of the leading candidates for nondestructive characterization of surface-treated metals because of its ability to probe the material properties at different penetration depths depending on the inspection frequency. We developed a high-precision laser-ultrasonic technique to study the feasibility of SAW dispersi...

National Institute of Standards and Technology, Boulder, Colorado 80303 Valid comparison of impact test energies reported by various organizations and over time depends on consistent performance of impact test machines. This paper investigates the influence of various specimen and test parameters on impact energies in the 1 J to 2 J range for both Charpy V-notch and Izod procedures, leading tow...

Localized electrochemical methods supported by surface analytical characterizations were employed to investigate galvanic coupling effects and local activity developed along the welded zones in Friction Stir Welded 2098-T351 Al-Cu-Li alloy. The investigation was carried out coupled weld joint/heat affected (WJ/HAZ) for both, retreating (RS) advancing (AS) sides. correlation between chemistry, m...

Accurate material behaviour and its response to loading are needed for a reliable calibration of ductile failure criteria. Non-quadratic yield functions often necessary such description. Nevertheless, it leads the prediction stress states that inconsistent with expected deformations in contradiction experiments when associated flow rule is adopted. These problems may be solved by applying less ...

A novel potentiometric Al3+−ion selective microelectrode (ISME), with internal solid contact, based on the use of a neutral carrier morin as ionophore is reported. The ability ISME to image local ion concentration distributions was tested aluminum alloy surfaces freely corroding in an aqueous solution containing chloride ions. then used sensing tip for scanning electrochemical microscopy (SECM)...

The present work applies a model for microstructural evolution in the solid state and Al–Cu–Mg alloys and expands it in a computationally efficient way to include solid–liquid reactions in fusion welds. The model is used to predict local strength and hardness of the welds, using a formulation that incorporates hardening due to two types of precipitates, i.e. Cu–Mg co-clusters and the S phase pr...