Research on creation and application of material models in the rolling process of medium and heavy plate leveler
Mechanical properties model of moderate/high temperature material affects leveling parameters setting. This article establishes the model as well as self-studying in rolling process and simplex optimizes the formulation of material model's deformation resistance. The model is established through this process which has a higher application in the actual production.
Investigation Into the Effects of Leveling Roll Diameter Variation on Coupling Shear Pin Breakage of a Hot Plate Leveler
A new model to calculate the effect of leveling roll size variation was developed based on contact mechanics. The model calculates the additional torque induced by the roll diameter variation and the tolerable roll diameter variation for integrated driving levelers.
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.