M.R. Sriraman

TL;DR: Welding of copper foils (150mm thick) achieved at room temperature by very high power ultrasonic additive manufacturing was seen to involve appreciable softening and enhanced plastic flow as discussed by the authors.

TL;DR: In this paper, the microstructures of Al alloy 6061 subjected to very high-power ultrasonic additive manufacturing were systematically examined to understand the underlying ultrasonic welding mechanism, and it was found that the weld interface between the metal tapes consisted of fine, equiaxed grains resulting from recrystallization, which was driven by simple shear deformation along the ultrasonically vibrating direction of the tape surface.

TL;DR: In this paper, thermal transients from the interface regions were recorded during processing of aluminum alloy (3003 and 6061 series) and 11,000 copper tapes under similar conditions, and the observed peak temperatures were seen to increase with increase in shear strength of the material and ultrasonic vibration amplitude.

TL;DR: In this paper, the electron backscattered diffraction technique was used to characterize the interface microstructure of 3003 aluminum alloy builds with constituent tapes using a very high power ultrasonic additive manufacturing (UAM) process.

TL;DR: In this article, thermal transients were observed over multiple interfaces of the build during welding of each layer and the temperatures were the highest for the layer processed and were found to diminish beneath with each subsequent layer.