Effect of Tensile Stress Rate on Transition Behaviours of a Low Carbon Steel

Abstract

The relationship between transition behaviour and temperature has been examined on a low carbon steel at various tensile stress rate.
The results obtained are summarized as follows:
(1) The stress σ_B at the point where a curve of fracture stress against temperature meets with that of yield stress against temperature seems to be a constant value independent of tensile stress rate.
(2) The relation between the transition temperature T_B at σ_B and the tensile stress rate V is represented by the following equation,
1/T_B=a-blogV
where a and b are constants.
(3) Micro-cracks may be formed by applying the stress above σ_B in the temperature range above T_B.
(4) It is considered that a yield slip is required for the nucleation of micro-cracks.