NON-STEADY EVOLUTION OF SUBHIGH RATE UNIDIRECTIONAL SOLIDIFICATION
亚快速单向凝固晶体生长的非稳态演化

Non-steady state evolution of crystal growth is still a problem seldom concerned by people in solidification,particular in the region of subhigh growth velocity after cell to dendrite transition. However,the final microstructure of materials is affected significantly by the non-steady state solidification process.The present paper is dealing with an investigation on the evolution of interface morphologies and the primary spacing of crystals at low and subhigh growth velocity and its evolution mechanism.The results show that the evolution characteristics of various interface morphologies,such as cells and dendrites,obtained under different solidification conditions and the mechanism of dynamic adjustment of primary spacing during non-steady state process are different.