Solidification characteristics of near rapid and supercooling directional solidification
来源期刊:中国有色金属学报(英文版)1999年第4期
论文作者:傅恒志 谢发勤
文章页码:659 - 667
Key words:alloy melt; solidification characteristics; supercooling directional soidification
Abstract: Comparing the solidification characteristics of supercooling directional solidification(SDS) with constrained directional solidification(D. S. ) and considering the inheritance of supercooled melt, the supercooling directional solidification technique with the combination of melt supercooing and traditional directional solidification was proposed. An exploring study on SDS techniques was also conducted by using appropriate selfmade facilities and the deep supercooling of Cu-5. O % Ni alloy and its directional solidification were implemented. The experimental results show that: 1 ) the solidification microstructure produced by SDS are nearly the same as that by LMC technique, its primary arm spacing is around 30 Um in average and the secondary sidebranch is considerably degenerated; 2) the primary arm trunk of microstructure appears straight and fine, and the average deviation of crystal growth orientation from the axial line is about 5. 8; 3) a mathematical model describing the relationship between melt supercooling by SDS and the solidification rate, namely T-T model,was established, by which the microstructure evolution in SDS can be explained.