No abstract

DryLyte® Technology is an effective surface finish technique, which follows the same traditional electrolytic cell principle, but uses an electrolytic solid non-conductive medium rather than a liquid one. For the last 10 years, this technology has been attracting a lot of attention compared to conventional ones due to the selective smoothing of the surface technique, interacting only with the roughness peaks and not with the valleys, etc. In this book’s chapter, for 3D-printed cemented carbides (WC-Co) polished with DryLyte® Technology, it is shown the correlation between the microstructure and the surface integrity, in terms of mechanical properties, at submicrometric length scale. Also, a particular case study is presented of 3D-printed WC-Co as a function of the testing temperature, ranging from room temperature up to service-like working conditions. Finally, the mechanical properties are correlated as function of the chemical nature and/or crystallographic phase.

The growing process of a spinel-like oxide film can be obtained through different atmospheres; in this sense Air, O 2 , steam, and nitrogen atmospheres were used in different steps during the aging heat treatment at 490ºC of maraging 300 and 350 alloys. The oxidation layer produced under different atmospheres was chemically, microstructurally and mechanically characterized by means of advanced techniques. The results showed (in both alloys) a non-homogeneous mix oxide formed by magnetite, nickel and cobalt ferrites and MoO 3 heterogeneously distributed along the oxide thickness. It was also founded TiO 2 in the innermost areas and a particularly important quantify of hematite on the external surface. A nickel-rich austenite phase was produced at the interphase due to the combination of nickel stability and the preference of cobalt, molybdenum, and iron diffuses through the film as ions. The highest thickness values were found in the oxides produced in maraging 300 steels which could indicate greater susceptibility to oxidation comparing with grade 350 maraging steel. The oxide films produced in both maraging alloys using air atmosphere presents excellent adherence, and the results show the capability for being used for tribological applications under sliding contact tests.