5th International Conference on Advances in Solidification Processes (ICASP-5) 5th International Symposium on Cutting Edge of Computer Simulation of Solidification, Casting and Refining (CSSCR-5)

The nucleation and Growth behaviors of primary Si particles in hypereutectic Al-Si-Cu alloys solidified under near-isothermal melt and constant cooling rate condition, have been studied by in-situ X-radiography. The influences of cooling rate and addition level of P on the nucleation temperature, maximum nucleation undercooling, nucleation rate, growth velocity and morphology development of primary Si particles were quantitatively studied. In addition, thermal analysis and ex-situ characterization of the TP-1 type solidification samples by SEM were performed. The in-situ experimental results were compared with TP-1 type solidification samples. An EBSD study has been conducted on the as-solidified in-situ X-radiographic samples to reveal the Growth crystallogrphy of the Si particles. The effect of P on the nucleation and growth of primary Si has been discussed based on experimental results and modeling results.