| Summary: | High-chromium white cast iron (WCI) specimens locally reinforced with WC–metal matrix composites were produced via an ex situ technique: powder mixtures of WC and Fe cold-pressed in a pre-form were inserted in the mold cavity before pouring the base metal. The microstructure of the resulting reinforcement is a matrix of martensite (α’) and austenite (γ) with WC particles evenly distributed and (Fe,W,Cr)<sub>6</sub>C carbides that are formed from the reaction between the molten metal and the inserted pre-form. The (Fe,W,Cr)<sub>6</sub>C precipitation leads to the hypoeutectic solidification of the matrix and the final microstructure consists of martensite, formed from primary austenite during cooling and eutectic constituent with (Fe,Cr)<sub>7</sub>C<sub>3</sub> and (Fe,W,Cr)<sub>6</sub>C carbides. The presence of a reaction zone with 200 µm of thickness, between the base metal and the composite should guarantee a strong bonding between these two zones.
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