CAJ | 학술논문

采用类金属透明模型合金丁二腈-1.0 wt%乙醇(SCN-1.0 wt%Eth)合金,考察了晶体取向对定向凝固过程中晶粒的平界面失稳孕育时间、枝晶形态演化以及枝晶一次间距的影响.结果表明,随着枝晶择优生长方向与温度梯度方向夹角的增大,晶粒的平界面失稳孕育时间增加,界面的稳定性增强;对于不同晶体取向的枝晶形态演化,枝晶择优生长方向与温度梯度方向夹角越大,枝晶二次臂不对称生长越严重,同时,具有生长优势的枝晶二次臂对相邻枝晶的生长的抑制越强烈;至于不同晶体取向的枝晶一次间距,随着枝晶择优生长方向与温度梯度方向夹角的增大,枝晶一次间距增大.
채용류금속투명모형합금정이정-1.0 wt%을순(SCN-1.0 wt%Eth)합금,고찰료정체취향대정향응고과정중정립적평계면실은잉육시간、지정형태연화이급지정일차간거적영향.결과표명,수착지정택우생장방향여온도제도방향협각적증대,정립적평계면실은잉육시간증가,계면적은정성증강;대우불동정체취향적지정형태연화,지정택우생장방향여온도제도방향협각월대,지정이차비불대칭생장월엄중,동시,구유생장우세적지정이차비대상린지정적생장적억제월강렬;지우불동정체취향적지정일차간거,수착지정택우생장방향여온도제도방향협각적증대,지정일차간거증대.
@@@@Dendrite is a typical pattern in directional solidification, attracting many theoretical and experimental researches. However, the effect of crystallographic orientation on dendrite growth is less considered in these researches. In this paper, using a transparent model alloy SCN-1.0 wt%Eth, the effects of crystallographic orientation on the incubation time of planar interface instability, the dendritical morphological feature, and the primary dendrite spacing in directional solidification are investigated. Three crystal grains with different angles between the dendrite axis direction and thermal gradient direction are chosen in our experimental. The experimental results show that the incubation time of planar interface instability increases with the deviation of dendrite axis from thermal gradient direction, which suggests that the deviation of dendrite axis favors the planar interface stability. And with the increase of deviation angle of dendrite axis, the side branches of dendrite become more asymmetric and the preferred side-branches suppress neighboring dendrite growth. Also it is found that the primary dendrite spacing becomes larger as the angle between the dendrite axis direction and thermal gradient direction increases.