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This paper presents results corresponding to the densification of WC-Fe composites. Commercial WC (4NPO H.C.Starck) was mixed with iron (Fe) added from a precursor obtained via sol-gel route. Results of the kinetics of phase formation in materials obtained via this sol-gel route, which involves several precursors of W, Fe and C, plus the addition of colloidal alumina (Al 2 O 3 ) are also reported. Samples with different concentrations of Fe were studied using a vertical dilatometer up to 1230ºC with 10% H 2 -Ar gas flow up to 800°C, and then in vacuum of 30mTorr until the final temperature. Densification is discussed in terms of kinetics analysis of selected experimental data to identify the different mechanisms involved. These samples were subjected to Xray diffraction to identify the resulting phases, where WC and W were the main phases. On the other hand, samples prepared from a sol-gel route containing Fe and alumina were treated under an atmosphere of 10% H 2 -Ar, in order to analyze the transformations produced in the temperature range 500 to 800°C. XRD studies indicated the formation of different phases, such as WC (of primary interest), and the subcarbide M 6 C type: W 3 Fe 3 C, among others. The analysis of all diffractograms indicates the evolution of the system as a function of temperature, leading first to oxidation (formation of FeWO 4 ) and reductions (formation of Fe) in the system. Simultaneous mass losses of this system are shown in the same range of 500-800°C.