Eutectic cell wall morphology and tensile embrittlement in ferritic spheroidal graphite cast iron

Journal Article · Thu Jul 01 04:00:00 EDT 1999 · Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science

DOI:https://doi.org/10.1007/s11661-999-0176-8· OSTI ID:677986

Shiao, F T; Lui, T S; Chen, L H; Chen, S F ^[1]

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1. National Cheng Kung Univ. (Taiwan, Province of China). Dept. of Materials Science and Engineering

Four ferritic spheroidal graphite (SG) cast irons (3.4C-3.9Si, 3.5C-2.7Si, 3.5C-2.0Si, and 2.0C-2.1Si, in wt pct) were chosen to study the eutectic cell morphology and the related tensile embrittlement. For the three test materials with high carbon concentration, the results indicate that the average eutectic cell wall size and the amount of cell wall inclusions decrease with decreasing silicon concentration. Compared to the test material with 3.5C-2.0Si, which has many inclusions dispersed in the ferrite matrix, the one with 2.0C-2.1Si shows larger average eutectic cell wall size and larger degree of inclusion clustering in the cell walls. Tensile embrittlement may occur in two temperature ranges, namely, the intermediate low-temperature range at the end of the upper elongation shelf and the intermediate high-temperature range of around 400 C. In both cases, the brittle cracks are initiated preferentially at the inclusion clusters in the eutectic cell wall region. Hence, the two tensile embrittlements occur only for the materials with a larger degree of inclusion clustering in the eutectic cell walls.

• Sponsoring Organization: USDOE
• OSTI ID: 677986
• Journal Information: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science, Journal Name: Metallurgical and Materials Transactions. A, Physical Metallurgy and Materials Science Journal Issue: 7 Vol. 30; ISSN 1073-5623; ISSN MMTAEB
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
CAST IRON
CRACKS
EUTECTICS
FERRITE
INCLUSIONS
MORPHOLOGY
TEMPERATURE DEPENDENCE
TENSILE PROPERTIES