Thixoforming : Semi-solid Metal Processing

Figure 5.11 Composition profiles of 100Cr6 after quenching at
300 K s –1 from 1418 C (50% liquid) simulated using DICTRA. The
dashed vertical line shows the original solid–liquid interface
before quenching. The dashed horizontal lines show the C and
Cr contents before quenching.
The (equilibrium) solidus temperature is given by:
T S ¼ 1337 C 173D%C 38D%Si 9D%Mn þ 2:9D%Cr ð5:9Þ
As for X210CrW12, C has the strongest influence, followed by Si.
5.3.4
Enthalpy, Heat Capacity and Density
The enthalpy of 100Cr6 around the semi-solid range is shown in Figure 5.12, the heat
capacity in Figure 5.13 and the density in Figure 5.14. The strong increase in the heat
capacity with temperature for the ferrite þ cementite curve is also in this case caused
by the ferromagnetic transition, although the Curie temperature is not quite reached
in this case.
5.3.5
Suitability for Semi-solid Processing
5.3 Calculations for the Bearing Steel 100Cr6j161
The liquid fraction curve in Figure 5.10 is fairly steep and without any particular
features, suggesting that it could be rather difficult to control the liquid fraction
reproducibly. 100Cr6 may be less prone to compositional variations than