MICROSTRUCTURAL ASPECTS OF FRACTURE IN AUSTEMPERED DUCTILE IRON.

Robert Carl Voigt, H. Dhane, L. Eldoky

Research output: Chapter in Book/Report/Conference proceedingConference contribution

9 Scopus citations

Abstract

The microstructural details of fracture in various austempered ductile irons have been investigated. Surface crack initiation and propagation were observed with the scanning electron microscope (SEM) upon incremental straining of a fracture test specimen at room temperature. Partially fractured specimens were fully fractured in a brittle manner so that the progress of existing partial cracks in the interior of specimens could also be observed. Upon initial straining, decohesion takes place between the primary graphite nodules and the austempered matrix. Localized plastic deformation is concentrated around the graphite nodules primarily in the ferrite laths or at ferrite/austenite interfaces. Microcracks initiate preferentially at many nodule sites and in intercellular delayed transformation regions where brittle microconstituents may be found. A large 'plastic zone' with many microcracks can be observed ahead of initiating or propagating crack fronts. The primary crack front grows or forms by successive link-up of favorably oriented microcracks.

Original languageEnglish (US)
Title of host publicationUnknown Host Publication Title
PublisherASME
Pages327-335
Number of pages9
ISBN (Print)0961721502
StatePublished - 1986

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All Science Journal Classification (ASJC) codes

  • Engineering(all)

Cite this

Voigt, R. C., Dhane, H., & Eldoky, L. (1986). MICROSTRUCTURAL ASPECTS OF FRACTURE IN AUSTEMPERED DUCTILE IRON. In Unknown Host Publication Title (pp. 327-335). ASME.