The Experiment Study On The Influnce Mechanism Of Oscillating Technology To Solidification Structure In Trc Strip

As a kind of near net shape cast-rolling technology, twin roll strip casting(TRSC) has advantages such as lower energy consumption and higher processing efficiency compared with the conventional continuous casting process. However, the structure of the conventional rolling-cast strip is non uniform, the grain is coarse, the columnar crystal is well developed, and the segregation in material is serious. All the above will decrease the mechanical property of materials. Aiming to those defects, the oscillating twin roll strip caster, adding vibration source to one roller of the traditional caster, will improve the flow field and the temperature field so that the structure can be refined and the segregation can be reduced. The present article mainly studied the effect of the oscillating technology to the strip structure, and aimed to find the optimum process parameters.By using the oscillating twin roll strip caster as the platform for experiment, the experiment scheme of oscillating casting was designed independently, and follow-up work was accomplished, including the design, manufacture, assemble and debug.The results of oscillating casting were analyzed compared with the conventional casting and the fast cooling without oscillating. By the observation of metallographic structure and the analysis of segregation, it’s found that the oscillating technology could refine grains, decrease the segregation, Improve mechanical properties eventually. At the same time, the macro defects, such as shrinkage cavity, shrinkage porosity and cracks, can also be improved.Considering the factors such as the separation between the strip and the rollers, we confirmed the choosing range of oscillating casting parameters, and lastly we chose 13 groups of oscillating parameter to conduct the casting orthogonal experiments. By comparing the results, the responsibility of the parameter range was verified.By comparing the results of different oscillation amplitude and frequency, it’s found that the oscillating technology could affect the flow field and the temperature field to break the dendritric crystal. Along with the increase of oscillation parameters within the25 Hz and 0.5mm, the nucleation rate will increase and equi-axed grain area will expand,the phenomenon of normal segregation and gravity segregation will be improved gradually.However, if the oscillation amplitude is over 0.5mm, the improving effect will not be obvious, and it will even deteriorate metal structure.