Ultrasonic Treatment On The Aluminum Alloy Solidification Process And Mechanical Properties Of Impact Studies

The purpose of this paper is to investigate the effect of the process of solidification and mechanical properties under ultrasonic field. The effect law of ultrasonic on the variance of temperature of alumium solidification process, microstructure and mechanical properties were tested and analyzed. Combining with theory analysis, the mechanism of ultrasonic on the solidification structure is discussed.The main reaserches were done as follows:1. The experimental system of ultrasonic casting was set up. The variance of temperature of pure aluminum and 7050 Al-alloy solidification process was tested respectively. The effects of ultrasonic power on solidification initial temperature and solidification time of the melts were analyzed contrastively. The experimental results show that: as the ultrasonic power increasing, the solidification initial temperature drops and the solidification time is shortened.2. The influence and the change tendency of ultrasonic treatment on the grain,hardness of aluminium and 7050 aluminium alloy have been studied. The experiment results show that the solidification grains have been refined by the ultrasonic treatment, and the tensile strength and hardness have been improved; the refinement on 7050 aluminium alloy is better than that of pure aluminium.3. The influences of ultrasonic on the solidification initial temperature, speed rate of nucleation and undercooling were theoretically analyzed. The relative mathematical model has been established. Combining with the detailed experimental results, the main mechanism of ultrasonic solidification refining has been analyzed from the thermodynamic.The research can provide a theoretical reference for the application of ultrasound in the process of aerospace aluminum alloy continuous casting and semi-continuous casting of large-size aluminum alloy ingots with a high-performance, so as to refine the solidification structure and improve the mechanical properties. Hope the development of ultrasonic aluminum casting technology can benefit from it.