Simulation of the rolling of stator vanes Harm Wisselink
Contact info: Harm Wisselink Han Huetink Martien van Dijk Andre van Leeuwen h.h.wisselink@wb.utwente.nl j.huetink@wb.utwente.nl ID_eldim@eldim.nl ID_eldim@eldim.nl Introduction ELDIM manufactures among others stator vanes for the compressor of an aero engine (figure 1). These vanes are produced by a cold rolling process. The development of a rolling process for a new type of vane can take several cycles of trial and error, before all requirements are fulfilled. from strips of sheet metal
Analysis of guillotining and slitting, finite element simulations
Guillotining and slitting are two sheet metal cutting processes, which produce long straight cuts and can be seen as stationary processes. The analysis of these two processes is the subject of this thesis. This research project is part of a cluster of IOP projects on sheet metal cutting, originating from industrial requests for more fundamental knowledge, as sheet metal cutting is still mainly based on experience and trial and error. The objective is to develop models of guillotining and slitting to increase the insight and to contribute to the quality and productivity of these shearing processes.
Joint strength of aluminum ultrasonic soldered under liquidus temperature of Sn–Zn hypereutectic solder
Abstract In order to obtain high-strength aluminum joints, ultrasonic soldering of 1070 aluminum was conducted under liquidus temperature of Sn–Zn hypereutectic solder. A device for ultrasonic soldering was assembled, which propagated ultrasonic vibrations in a direction perpendicular to joining surfaces. This device joined 1070-Al using quasi-melting Sn–Zn hypereutectic solder without using any artificial spacers. The strength of the solder joints was evaluated by tensile tests. The optimum joining conditions were determined, and the effects of solder compositions and soldering temperature on the joint strength and the solder layer thickness were examined. In this ultrasonic soldering process, the highest tensile strength was obtained for the solder joints fabricated at 220 °C for the Sn–23Zn and Sn–40Zn solder compositions. The joint strength was equivalent to that of 1070-Al heat treated at 220 °C. The sound joints were obtained at 300 °C using Sn–82Zn solder, the liquid phase volume fraction of which was theoretically only 0.24. The present work also revealed that the thickness of retained solder layer in the joint after ultrasonic soldering could be estimated. Accordingly, ultrasonic soldering under the liquidus temperature of Sn–Zn hypereutectic solder could be a spacer-free soldering method to obtain high-strength aluminum joints.