Research Of The Die-Casting Sonication System

ABSTRACT:Grain size is a major factor in determining the material properties. There are many methods of grain refinement, as used herein, the sonication. Grain refinement by ultrasonic treatment relies mainly on partial instantaneous high temperature and pressure and a strong shock wave that created by ultrasonic cavitation. Break dendrite growth, and with ultrasonic acoustic streaming effects, thermal effects, and so on, enhance the rate of nucleation, refine the grain. This article focuses on introducing the ultrasonic transducer and ultrasonic treatment instrument. Ultrasound probe design includes structural design, parameter design and shell installation design. While ultrasonic treatment instrument mainly introduces its special working conditions in die-cast, its functionality and workflow. In addition, this paper also analyzes the experimental data, and summarizes the problems of the existing ultrasonic treatment system.This paper also observes and analyzes microstructure and mechanical properties of experimental samples, but experimental data does not fit well with the relationship between metal sonication and grain refinement. The main reasons are the following two points:first, the frequency of the ultrasonic transducer shifted, thereby affecting the ultrasonic power output, while ultrasonic frequency and power are the main parameters affecting the grain refining effect of metal; second, due to the ultrasound probe is located in die casting cavity, resulting in a short processing time, only tens of milliseconds, sonication is not obvious. Propose a solution for the above two reasons: first, the additional frequency tracking device, makes ultrasonic treatment instrument automatically track the load of ultrasound probe, and adjusted to the optimum frequency; second, changing the position of the ultrasound probe, increase sonication time.