Stress-Affected Bainitic Transformation in a Fe-C-Mn-Si Alloy
A. Matsuzaki, H. K. D. H. Bhadeshia and H. Harada
Abstract
Isothermal transformation experiments are reported in which the formation of bainitic ferrite occurs under the influence of stresses below the yield strength of the austenite. The response of the
transformation was monitored by simultaneously measuring the longitudinal and radial transformation strains. This enabled the dilatational and deviatoric strain components to be deconvoluted from the
total transformation strain. The data have been analysed by comparison with a theoretical model for the stress-assisted growth of bainite. The results confirm that the microstructure readily responds
to stresses well below the yield strength of the parent phase. Furthermore, those crystallographic variants which are favoured by the stress grow first in the sequence of transformation. Experiments
where the stress just exceeds the yield strength are also reported.
ACTA METALLURGICA ET MATERIALIA, 1994, Vol.42, No.4, pp.1081-1090
