The properties of the double iron and tungsten carbide prepared by mechanical alloying technique (MA) from elemental powders are reported. The samples were milled for 1, 3, 5, 10, 15, 20, 25 and 30 h. The alloy progress for each milling time was evaluated by X-ray diffraction (XRD) and 57 Fe Mössbauer spectrometry. Once the alloy was consolidated two sorts of paramagnetic sites and a magnetic distribution were detected according to the Mössbauer fitting. The majority doublet could correspond to Fe 6 W 6 C ternary carbide as X-ray diffraction suggests, and the other could be Fe 3 W 3 C. The hyper fine parameters are reported. Vickers microhardness measurements of 30 h milled sample was conducted at room temperature with a load of 0.245 N for 20 s.

Iron silicon carbide Fe 0.79 Si 0.09 C 0.12 was prepared by mechanical alloying from elemental powders, with a ball-to-powder weight ratio of 20:1. This synthesis was carried out in two stages: in the first stage cementite Fe 3 C was prepared from elemental iron and carbon powders, the mixed powders were milled for 30 hours. In the second stage Fe 0.79 Si 0.09 C 0.12 was prepared from cementite Fe 3 C and Silicon elemental powder as precursors, the samples were milled for 1, 3, 5, 10, 15, 20, 25, 30 and 35 hours. The alloy progress for each milling time was evaluated by X-ray diffraction (XRD) and 57 Fe Mössbauer spectrometry. Nanocrystalline Fe 3 C powders were obtained from Fe and C, with an average grain size of 15 nm. It was possible to prepare metastable iron silicon carbide such as Fe 0.79 Si 0.09 C 0.12 and Fe 0.81 Si 0.02 C 0.17 and their respective hyperfine parameters are reported.

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Double iron and aluminum carbides were prepared by mechanical alloying from elemental powders, with a ball-to-powder weight ratio 20:1. The samples were milled for 1, 3, 5, 10, 15, 20 and 25 h. The alloy progress for each milling time was evaluated by X-ray diffraction (XRD) and 57 Fe Mössbauer spectroscopy. Once the alloy was consolidated two sorts of paramagnetic sites and a magnetic distribution were detected according to the Mössbauer fit. The majority doublet could correspond to Fe 3 AlC 0.5 carbide as X-ray diffraction suggest, and the other could be Fe 3 AlC 0.69 ; the magnetic distribution corresponding to Fe 3 Al phase, Fe 7 C 3 and Fe 5 C 2 single carbides. The hyperfine parameters are reported.