Modeling and characterization of as-welded microstructure of solid solution strengthened Ni-Cr-Fe alloys resistant to ductility-dip cracking part I: Numerical modeling

Autor(es)

Unfried-Silgado, Jimy ^{[1, 2, 3]} ; Ramirez, Antonio J. ^[1]

Afiliação do(s) autor(es)

^[1] CNPEM ABTLuS, Brazilian Nanotechnol Natl Lab, Met Characterizat & Proc Lab, Campinas, SP - Brazil

^[2] Univ Estadual Campinas, UNICAMP, Fac Engn Mecan FEM, Campinas, SP - Brazil

^[3] Univ Autonoma Caribe, Programa Ingn Mecan, Grp IMTEF, Barranquilla - Colombia

• Tipo de documento: Artigo Científico
• Fonte: METALS AND MATERIALS INTERNATIONAL; v. 20, n. 2, p. 297-305, MAR 2014.
• Citações Web of Science: 2

Resumo

This work aims the numerical modeling and characterization of as-welded microstructure of Ni-Cr-Fe alloys with additions of Nb, Mo and Hf as a key to understand their proven resistance to ductility-dip cracking. Part I deals with as-welded structure modeling, using experimental alloying ranges and Calphad methodology. Model calculates kinetic phase transformations and partitioning of elements during weld solidification using a cooling rate of 100 K.s(-1), considering their consequences on solidification mode for each alloy. Calculated structures were compared with experimental observations on as-welded structures, exhibiting good agreement. Numerical calculations estimate an increase by three times of mass fraction of primary carbides precipitation, a substantial reduction of mass fraction of M23C6 precipitates and topologically closed packed phases (TCP), a homogeneously intradendritic distribution, and a slight increase of interdendritic Molybdenum distribution in these alloys. Incidences of metallurgical characteristics of modeled as-welded structures on desirable characteristics of Ni-based alloys resistant to DDC are discussed here. (AU)

• Processo FAPESP: 06/05661-1 - Estudo do mecanismo de fratura intergranular por queda de ductilidade em ligas Ni-Cr-Fe
• Beneficiário: Jimy Unfried Silgado
• Modalidade de apoio: Bolsas no Brasil - Doutorado