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Two boride layers based on the FeB and Fe 2 B compounds are formed at the interface between an Fe-15Cr alloy and boron at 850-950uC and reaction times up to 12 h, with the average chromium content being around 8 at-% in the former and 12 at-% in the latter. Both boride layers reveal a pronounced texture. Diffusional growth kinetics of the layers are close to parabolic and can alternatively be described by a system of two non-linear differential equations. Microhardness values are 17?4 GPa for the FeB layer, 14?4 GPa for the Fe 2 B layer and 0?95 GPa for the Fe-15Cr alloy base. The dry abrasive wear resistance of borided alloy samples is around 45 times greater than that of non-borided ones.

Two boride layers were found to form at the interface of iiron-chromiium alllloys (10 and 25% Cr) or an industrial 13% Cr steel and boron at 850-950 oC and reaction times in the range 1-12 h. In the case of a Fe-10% Cr alloy and the steel, the layers are based on the FeB and Fe2B compounds. With a Fe-25% Cr alloy, the constituent phases are FeB and CrB for the outer layer and Fe2B and Cr2B for the inner layer. Both layers are characterized by a pronounced texture. Diffusional growth kinetics of boride layers are close to parabolic and can alternatively be described by a system of two non-linear differential equations, producing a good fit to the experimental data. The temperature dependence of the layer growth-rate constants obeys a relation of the Arrhenius type.

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