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The effectiveness of ultrasonic velocity measurements was evaluated as a means for nondestructive characterization of cold-rolled copper and 68:32 brass sheets. An apparatus was designed to generate and receive the zeroth symmetrical mode of ultrasonic Lamb waves in thin copper and brass sheets. The effect of angular variations in propagation direction with respect to the rolling direction on the measured Lamb wave velocities is shown. Interpretation of the variations of ultrasonic Lamb wave velocity were related to deformation mechanisms and texture development in copper and 68:32 brass sheets. Results show that the grain size and cold work influence the velocity as well as the texture of copper and 68:32 brass sheets. Results indicate the possibility of using ultrasonic Lamb wave velocity as a tool to monitor elastic anisotropy.

In this paper we report the effects of Equal Channel Angular Extrusion (ECAE) processing on the phase transformation characteristics of Ni-Ti based shape memory alloys in terms of transformation temperatures, temperature hysteresis, and microstructural evolution. The ECAE process affects the material’s shape memory behavior via microstructural refinement. Differential Scanning Calorimetry (DSC) and Transmission Electron Microscopy (TEM) were utilized to investigate the effects of microtructural refinement and substructure formation on the shape memory behavior of these alloys. The microstructural refinement was found to have significant influence on the transformation temperatures.