汽车活塞合金初生硅形核生长机制探讨

Discussion on the mechanism of primary silicon's nucleation and growth process of automobile piston alloy

通过XRD、光学显微镜等手段研究了P变质汽车活塞用过共晶Al-20Si合金的微观组织和相组织,对初生硅相的形核生长机理做了进一步的分析,结果表明:存在Al P异质形核不容质疑;但是还存在均匀形核的可能,这从同一试样的组织形貌中可以分析出,但在结晶过程中哪种形核机制占主导地位尚未清楚,需要进一步研究。

In this paper,study on microstructure and phase organization of P metamorphic Al-20Si which used in piston of automobile by means of optical microscope and XRD,further analysis on the mechanism of primary silicon’s nucleation and growth has been don e.The results show:AlP heterogeneous nucleation has no doubt;whereas homogeneous nucleation is also exist,this can obtain from the same sample’s morphology,but in the process of crystal nucleation which mechanism dominated has not clear,needs further study.