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Indexed by:期刊论文

Date of Publication:2006-04-01

Journal:TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA

Included Journals:SCIE、EI、ISTIC

Volume:16

Issue:2

Page Number:235-241

ISSN No.:1003-6326

Key Words:turbine blade; dendrite envelope tracking model; structure simulation; unidirectional solidification

Abstract:A 3D dendrite envelope tracking model was developed for estimating the solidification structure of unidirectionally solidified turbine blade. The normal vector of dendrite envelope was estimated by the gradient of dendrite volume fraction, and growth velocity of the dendrite envelope (dendrite tips) was calculated with considering the anisotropy of grain growth. The solute redistribution at dendrite envelope was calculated by introducing an effective solute partition coefficient(k(e)). Simulation results show that the solute-build-up due to the rejection at envelope affects grain competition and consequently the solidification structure. The lower value of ke leads to more waved dendrite growth front and higher solute rejection. The model was applied to predict the structure of turbine-blade-shape samples showing good ability to reproduce the columnar and single grain structures.