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In this work it is carried out an assessment of the influence of the carbon contents in the base metal on the morphology of carbide layers and adjacent zones, which were obtained by using refractory saturate mixture elaborated from refractory chromite for steels AISI 1045, AISI 1055 W108 and gray cast iron. It is also analyzed the effect of carbon content in the base metal on the depth, micro-hardness values and phase composition of the carbide layer achieved for those steels. The carbide coatings obtained are defined for to be maximum micro-hardness values of » 1600 Hv20, levels depths among 9-23 mm (for an exposition regime of 1 000 °C-4 h), and due to the fact that they are formed by (Cr, Fe)23C6 y (Cr, Fe)7 C3 phase. [ABSTRACT FROM AUTHOR]

A characterization of coating obtained from the cuban chromite and boric acid as sources of the saturating elements using optical microscopy, x-ray diffractometry and scanning electronic microscopy was carried out. The layers present phases of complex chromium carbides of the type (Cr, Fe) 23 C6, (Cr, Fe)7 C3. The contents of chromium and iron in the layers vary with the saturated mixtures composition. [ABSTRACT FROM AUTHOR]

In this work the simultaneous method of solid saturation is applied to obtain chromium carbide layers alloyed with boron on steel using chromite ore and boric acid as sources of the diffusion elements. The saturates mixtures was obtain from aluminothermy previous way to the process of saturation. By means of a experiment design the influence of the variables studies relation chromium/boron in the saturate mixtures and type of tool steel on the thickness and the micro-hardnesses of the diffusive layers. The obtained coatings are characterized by maximum levels of micro-hardness between 1800 and 1900 Hv20 and thicknesses of agreed layer with the regime of saturation and the used substratum. [ABSTRACT FROM AUTHOR]