Effect of niobium in solid solution on the transformation kinetics of bainite

G. Rees, J. Perdrix, T. Maurickx and H. K. D. H. Bhadeshia

Abstract

A study is made of the effect of niobium in solid solution in microalloyed austenite (γ) on the kinetics of transformation to bainite (α_b) upon cooling, using a combination of dilatometry, scanning and transmission electron microscopy. The steels investigated are three labouratory melts with systematic variations in niobium concentration, and an industrial microalloyed grade.

Results indicate that increasing niobium content retards the bainite transformation but that, while significant, this effect is rather small. A much more dramatic effect on bainite formation is produced by allowing a small amount of niobium carbo-nitride precipitation in the austenite before cooling.

This paper won the 1996 Charles Hatchett Award from the CBMM (Brazil) and the Institute of Materials, London.

Materials Science and Engineering A 194 (1995) 179-186.

Download PDF file of paper (5 Mb)

This file is reprinted from Materials Science and Engineering with permission from Elsevier Science. Single copies of the article can be downloaded and printed for the reader's personal research and study.

Audio podcast Study guide