Influence of Supercooling on Formation of Primary Phase

14th International Conference on Modelling of Casting, Welding and Advanced Solidification Processes

材料科学;机械制造

Yoshimura, R.^1 ; Esaka, H.^2 ; Shinozuka, K.^2

National Defense Academy, 1-10-20 Hashirimizu, Yokosuka

239-8686, Japan^1

Department of Materials Science and Engineering, National Defense Academy, 110-20 Hashirimizu, Yokosuka

239-8686, Japan^2

关键词: Cast products;    Equilibrium value;    Internal crack;    Primary phase;    Shrinkage cavities;    Solidified structures;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/84/1/012060/pdf
DOI  :  10.1088/1757-899X/84/1/012060

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

It is reported actual volume fraction of primary phase in alloys is larger than the equilibrium value. Larger volume fraction of the primary phase may cause shrinkage cavities and surface or internal cracks. Although control of solidified structure is important for the quality of cast products, this problem has not been elucidated. Taking these results into account, this study has been carried out in order to comprehend a phenomenon of larger volume fraction of primary phase. Sn-Pballoy has been used as a test alloy and to examine the relation between supercooling for nucleation and the volume fraction of primary phase has been mainly characterized. Actually, volume fraction of primary phase in Sn-Pballoy is larger than that of lever rule. It was also observed that the volume fraction of β-Sn decreases with decreasing the supercooling in early stage of solidification. In the final stage of solidification, however, the effect of supercooling on volume fraction of primary phase is small. Furthermore, when the supercooling was low, volume fraction of primary phase was slowly increased.