Grain refinement effects of Al based alloys with low titanium content produced by electrolysis

摘要

A series of Al based alloys with low titanium contents (mass fraction) from 0. 178% to 0. 526% were directly produced in ordinary industrial electrolyzer. The electrolyzing results show that producing Al based alloys with titanium contents of less than 0. 30% without great loss of electrolysis efficiency is possible. The quantitative analysis shows that this method has a great refining effect on transiting the coarse columnar grains in pure Al to e-quiaxed grains. The grain sizes decrease with the increase of titanium content and tend to a low limit at about 130 μm. During the solidification, the non-equilibrium distribution of titanium leads to a great growth-restricting effect and a constitutional under-cooling zone in front of the growing liquid /solid interface.