Coarsening and dendritic instability of spheroidal graphite in high silicon cast iron under thermal cycling in the ferritic domain

SCRIPTA MATERIALIA

卷:178

Article

Ebel, Andre^1,2  Pegoraro, Mariana Alves¹  Malard, Benoit¹  Tenailleau, Christophe¹  Lacaze, Jacques¹ 

[1] Uniyersite Toulouse, CNRS, CIRIMAT, ENSIACET, BP 44362, F-31030 Toulouse 4, France

[2] Univ Bordeaux, LCTS, Bordeaux, France

关键词: Cyclic heat treatment;    Dendritic growth;    Graphite;    Spheroidal graphite cast iron;   

DOI  :  10.1016/j.scriptamat.2019.11.001

来源: Elsevier

【 摘 要 】

High silicon ferritic spheroidal graphite cast irons have been developed for high temperature service, in particular under thermal cycling conditions. The theoretical maximum service temperature is defined as the upper limit of the two-phase ferrite+graphite domain, which increases with the alloy silicon content. While isothermal heat treatment close to this temperature showed little evolution of the graphite distribution, thermal cycling led to a significant coarsening of the graphite particles associated with dendritic overgrowth of the large graphite particles. This unexpected behaviour is here observed and described for the first time. (C) 2019 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free