A third-generation synchrotron radiation imaging technique combined with a high-resolution fast-readout CCD(Charge Coupled Device) system was applied to study the dendrite growth of metallic alloy with high resolution images.As one of the first group users of Shanghai Synchrotron Radiation Facility(SSRF)
we acquired a series of animated images of dendrite growth at different cooling rates
using the in-line holography imaging method.At an increased cooling rate
the dendrite grew in an equiaxed manner
the nucleation rate became higher
and the secondary DAS(dendrite arm spacing) reduced greatly.In addition
the formation of microsegregation was affected greatly by the cooling rate.