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The back-face tilt of press-hardened crown wheels is investigated for continuous and ingot cast material. Two different geometries are studied, one with a flat back-face and one with a step. For two ingots, the original material position is tracked and coupled to back-face tilt, cross section hardness and chemical segregation. The chemical gradients are shifted from top to bottom of the ingot and are strongly coupled to the back-face tilt.

The thermodynamic description of the Ti-W system is reevaluated using simpler models than in a recent evaluation. The phase diagrams, calculated from the two descriptions, are rather similar but the present calculation gives a higher liquidus which is supported by experimental information in the Ti-W-C system. The new description of the Ti-W system is then combined with the previously assessed Ti-N and W-N systems, yielding a consistent thermodynamic description of the ternary Ti-W-N system. The ternary phase diagram is predicted by calculations.

The Ti-W-C system is assessed and the phase diagram is presented through various sections and projections. In general, good agreement is obtained between calculations and experiments. The TiC-TiN-WN-WC section is calculated at graphite saturation in the quaternary Ti-W-C-N system. The calculated miscibility gap in fcc is metastable in agreement with experimental observations. The calculated WC solubility and isoactivity lines of N in fcc compares favourably with some experimental information. Finally, the underlying W-C-N system is predicted by calculations.

Experimental work on the Ti-C system is reviewed and a thermodynamic description of the Ti-C system is presented. The thermodynamic properties of TiC y are considered in detail and calculated titanium and carbon activity compare reasonable well with experimental information. Phase boundaries are well reproduced except in the vicinity of ordered TiC y , which is not considered. The congruent melting point of TiC y and the three-phase temperatures are well reproduced. The assessment procedure is described and the result is compared with previous descriptions. The phase diagram is calculated at 1 bar with and without the gas phase. The potential phase diagram without gas is also presented.

The thermodynamic properties of the Ti-C-N system is assessed using previous assessments of the Ti-C and Ti-N systems and experimental information on the ternary system. The liquid phase is described over the whole range of composition using a substitutional model and the fcc titanium carbo-nitride in the Ti-TiC-TiN triangle using a two-sublattice model (Ti) 1 (Va, C, N) 1 . A metastable miscibility gap occurs in the fcc phase and part of it appeared to be stable in previous assessments. Isothermal sections are calculated and compared with experimental information from 773 to 1923 K. The liquidus surfaces and the minimum pressure needed to prevent boiling of the liquid are calculated. The isoactivity lines in fcc for titanium, carbon and nitrogen are calculated at 1923 K.