Evaluación de los productos de la reducción de un concentrado cromífero en la obtención de recubrimientos difusivos de carburos de cromo

The raw materials traditionally used as sources of chromium carriers (ferrochromium, chromium oxide and chromium powder) in application chromizing processes present a high price and some difficulties for ferrochromium grinding. In this work there is an assessment of the effect that has the use of the products of a reduction aluminothermic chromium concentrate on the characteristics and properties of diffusive chromium carbide complex coatings. To assess the coatings optical microscopy, micro – hardness test, Ray X diffractometry and Energy Dispersive Ray X Spectroscopy was used. It has determined that the implementation of diffusive treatments using a treatment regimen of 1 000 oC – 4 h giving complex carbides chromium coatings in three substrates researched (AISI 1055 steel, W108 tool steel and grey cast iron). The layers do not differ by their morphology of those reported in previous work and are characterized as having similar levels of microhardness and similar or high thicknessesthat achieved using conventional sources carrying chromium in chromizing. Also coatings are highlighted by high contents of chrome that possess (among 65 and 71 % for steel AISI 1055).In addition, it was found that mixtures of products made with the reduction of chromium concentrate possess the ability to make chromium necessary for the normal development diffusive process with a durability of at least four processes without the need for its revival, for the experimental conditions used.