摘要
The growth mechanism of the peritectic η phase involving the peritectic reaction and peritectic transformation in Cu-70%Sn alloy was investigated under directional solidification. The results show that a major growth mechanism in thickening of the peritectic η-layer is not the peritectic reaction but the peritectic transformation. The transformation temperature and isothermal time play crucial roles in determining the volume fraction and the thickness of the peritectic η phase. With the increase of the temperature and isothermal time, the volume fraction of the peritectic η phase increases. The regressed data show that the relationship between the thickness of η phase (Δx) and the transformation temperature (T) meets the following equation In Δx=6.5?1673 1 / T. Additionally, there exists a relationship between the thickness of the η phase (Δx) and the isothermal time (t) at the 9 mm solidification distance below the peritectic reaction interface, Δx=0.72t 1/2, which is consistent with the theoretical model.
The growth mechanism of the peritectic η phase involving the peritectic reaction and peritectic transformation in Cu-70%Sn alloy was investigated under directional solidification.The results show that a major growth mechanism in thickening of the peritectic η-layer is not the peritectic reaction but the peritectic transformation.The transformation temperature and isothermal time play crucial roles in determining the volume fraction and the thickness of the peritectic η phase.With the increase of the temperature and isothermal time,the volume fraction of the peritectic η phase increases.The regressed data show that the relationship between the thickness of η phase(x)and the transformation temperature(T)meets the following equation ln x=6.51673 1T.Additionally,there exists a relationship between the thickness of the η phase(x)and the isothermal time(t)at the 9 mm solidification distance be-low the peritectic reaction interface,x =0.72t1/2,which is consistent with the theo-retical model.
基金
Supported by the National Natural Science Foundation of China (Grant No. 50395102)
