Morphology of bainite and Widmanstaetten ferrite

Journal Article · Thu Sep 01 04:00:00 EDT 1994 · Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States)

OSTI ID:7157400

Ohmori, Yasuya; Ohtsubo, Hiroyuki; Jung, Y C ^[1]; Okaguchi, Shuji; Ohtani, Hiroo ^[2]

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1. Ehime Univ., Matsuyama (Japan). Dept. of Materials Science and Engineering
2. Sumitomo Metal Industries, Amagasaki (Japan). Iron and Steel Research Labs.

Morphology of bainite and Widmanstaetten ferrite in various steels has been investigated by means of microstructural and surface relief observations. It was shown that upper and lower bainite should be classified by ferrite morphology, i.e., lathlike or platelike, and that the morphology of cementite precipitation cannot be the index for the classification. Widmanstaetten ferrite formed in the upper C-nose where ferrite grain-boundary allotriomorphs nucleate exhibits quite similar appearance with bainitic ferrite that forms in the lower C-nose of bainitic reaction. The only difference between them exists in the fact that Widmanstaetten ferrite laths grow in the temperature range where primary ferrite forms and often terminate at a grain boundary ferrite but that bainitic ferrite has its own C-curve at temperatures below B[sub s] and nucleates directly at an austenite grain boundary. The mechanisms for their formations are discussed.

• OSTI ID: 7157400
• Journal Information: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States), Journal Name: Metallurgical Transactions, A (Physical Metallurgy and Materials Science); (United States) Vol. 25:9; ISSN 0360-2133; ISSN MTTABN
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360102* -- Metals & Alloys-- Structure & Phase Studies
ALLOYS
BAINITE
CARBON ADDITIONS
CRYSTAL-PHASE TRANSFORMATIONS
DATA
EXPERIMENTAL DATA
FERRITE
INFORMATION
IRON ALLOYS
IRON BASE ALLOYS
MICROSTRUCTURE
MORPHOLOGY
NUCLEATION
NUMERICAL DATA
PHASE TRANSFORMATIONS
STEELS
TEMPERATURE DEPENDENCE