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在高梯度定向凝固装置中采用枝晶方向与热流偏离的籽晶制备AM3晶体,分析晶体生长过程中杂晶的形核原理和不同晶粒的竞争淘汰机制。结果表明,枝晶方向与热流偏离造成的过冷可促使杂晶的形成。枝晶生长方向与热流偏离较大的晶粒在一定条件下可淘汰枝晶方向与热流接近的晶粒;晶粒的竞争与淘汰过程受晶粒间枝晶的相对位向、晶粒生长方向与热流方向的夹角大小、晶粒的晶体取向等因素有关。
In the high gradient directional solidification apparatus, the AM3 crystal was prepared by using the dendritic orientation and heat flux deviation from the seed crystal, and the nucleation mechanism of the miscellaneous crystal during crystal growth and the competition and elimination mechanism of different crystal grains were analyzed. The results show that the dendrite direction and heat flow caused by the supercooling can promote the formation of miscellaneous crystals. Dendrite growth direction and the larger the deviation of the heat flow under certain conditions can be eliminated dendrite direction and heat flow close to the grain; grain competition and elimination process by the intergranular dendrite relative orientation, grain growth direction And the direction of the heat flow rate of the size of crystal grain orientation and other factors.