考虑包晶反应的Ti--(45---48)Al合金锭凝固组织模拟.pdf

l l s Vol No i i ACTA METALLURGICA SINICA Apr pp dF TiAl QZnK
il       DCe   ZKBfah TiAlcE qlAfNVoanKa acfalNcXwmfahCfNVLPB RPfAXFWqfahZKBWveUpCygLgLah BafBlElfLahKvyfrCZaIAfrbTXh fANAfrbfErb LW TiAl qahlavV DIO TG tf A O SOLIDIFIED STRUCTURE SIMULATION OF TiAl ALLOY INGOT WITH CONSIDERATION OF PERITECTIC REACTION LIU Dongr ong WU Shiping GUO Jingjie SU Yanqing FU Hengzhi Department of Materials Science and Engineering Harbin Institute of Technology Harbin Correspondent LIU Dongr ong Tel Email hitldr com Supported by National Natural Science Foundation of China No Manuscript received in revised form ABSTRACT Solidied structure mo deling of TiAl alloy atomic fraction ingot has b een carried out by using a new cellular automaton metho d coupled with macroscopic heat transfer calculation Cells are divided into primary and p eritectic ones Dierent cells take the dierent so lidication paths By the new metho d the formation of p eritectic phases can b e shown graphically throughout solidication The formation of shrinkage cavity at the top of the ingot is included in the calculation A sp ecialmovingallo cation technique is designed to minimize the computation costs and memory size asso ciated with a large numb er of cells The p otentiality of the present mo del is demonstrated by comparing the simulated results with the exp erimental one The inuences of convec tion and initial alloy comp osition on the grain structures are studied and the mechanisms pro ducing ulated results indicate that the size of equiaxed zone increases