A Study of Deformation Characteristics of Mn-V Dual Phase Steel
Abstract:
The deformation characteristics of dual phase steels have been investigated. The true stress-strain curves were calculated from conventional stress-strain curves measured in Instron 1251. Three empirical formulae were used to approach these curves and C-J method was used to analyze them respectively. It is found that there is a "double n" characteristic in the uniform deformation stage. Based on the results of calculation and observation of microstructure, it is suggested that deformation and work-hardening characteristics in the uniform deformation stage of dual phase steels may be described with what we called "Ashby Mileiko's comprehensive theory", i.e. initial work-hardening due to incompatibility
of two phases may be explained by Ashby's theory. After the strain and work-hardening in the ferrite reached to certain extent martensite began to deform. In this stage the deformation characteristic of dual phase steels may be described by Mileiko's theory which has been used to explain the strengthening mechanism of composite. According to this comprehensive theory in order to increase the initial work- hardening rate and uniform elongation of dual phase steels, it is necessary that under the given reasonable martensite volume fraction, the size of martensite island and ferrite grain should be reduced, the amount of lath martensite in martensite island should be increased and martensite island should be distributed as evenly as possible.
Keywords:
vanadium, dual phase steel.
Author:
M. Ma, D. Wang, B. Wu
Affiiation
Central Iron and Steel Research Institute, Beijing, China
PDF:
Source:
Vanadium Structural Steels - Reprint of papers on vanadium steel from the proceedings of “ASM HSLA Steels Technology and Applications Conference, Philadelphia, USA, Oct., 1983, pp. 153-160
PDF Preview:
