Efecto del zirconio en la microestructura y resistencia al desgaste de un hierro blanco alto-cromo

Abstract

White foundries are characterized by high hardness, which in turn is associated with a high degree of fragility. This type of alloy is generally used in applications where it requires a lot of hardness and wear resistance, as well as a certain degree of tenacity. In this research work a comparative study was carried out between a white iron, whose approximate chemical composition is 17%Cr, 77,5%Fe, 3%C, 1%Mo, 1%Ni, 0,5%Si, and a white iron with the same components, but with an addition of 1%Zr. For microstructural characterization of the material was used: conventional optical microscopy, scanning electron microscopy and X-ray diffraction. By performing the thermal treatment by destabilization, the transformation of the austenitic matrix to martensitic was generated, increasing the hardness and resistance to the wear of the foundries, as well as the appearance of secondary carbides. Mechanical behaviour was analyzed through Rockwell C hardness tests. Moreover, for the analysis of wear resistance, wear tests will be performed by sliding and abrasive wear, that were assessed by the tests Block-on-Ring and Dry Sand/Rubber Wheel respectively.