Conversional model of transformation strain to phase fraction in low alloy steels

Prediction of Martensite Volume Fraction in Fe–Cr–Ni Alloys

“…[16][17][18] Good agreement between the measured and calculated volumes of martensite was confirmed when the effect of the alloying element was considered (called the "AE" calculation). Similarly good correspondence has been observed in the previous models [2][3][4][5][6][7][8] used for heat-treatable low-alloy steels when the alloying elements are considered. The other calculation performed (called the "CE" calculation) considered only the carbon effect on the lattice parameters without any other alloying effects, and is shown in Eqs.…”

“…Dilatometric analysis has been widely used for determining quantitative volume fractions of transformed phases, and many investigations have provided analytical models for converting dilatometric data into volume fractions of the constituent phases. [2][3][4][5][6][7][8] However, most of these previous models have been mainly focused on heat-treatable low-alloy steels whose total amount of alloying element is below 5 wt%. The principle used in these models for dilatometric analysis is based on the relative atomic volume change between parent phase and transformed phase.…”

A Model for Converting Dilatometric Strain Measurements to the Fraction of Phase Formed during the Transformation of Austenite to Martensite in Powder Metallurgy Steels

“…More accurate models for converting the transformation strain obtained from dilatometric measurements to volume fraction of phase formed have been recently developed. [2][3][4][5][6] Most of these models are based on converting the measured dilatometric strain to a volume change that is assumed to be caused entirely by the difference in crystal structure between the parent phase (e.g., fcc austenite-c) and the product phase (e.g., bct martensite-a¢). These models, although more accurate than the Lever Rule model, were developed for the transformation of c to proeutectoid ferrite or pearlite, and specifically for wrought steels.…”

Ab initiocalculation of the solution enthalpies of substitutional and interstitial impurities in paramagnetic fcc Fe

“…1. The experimental data were acquired using neutron diffraction, which seems to be a more suitable technique for determining the lattice parameter of austenite in Fe-C alloys at high temperature due to reduced sensitivity to surface decarburization [36,37]. The lattice parameters of Fe 108 C 1 and Fe 108 C 2 supercells were chosen so that their pressure corresponded to that of the Fe supercell.…”