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Homogeneous (HM) and functionally graded (FG) TiN thin films were produced by the grid-assisted magnetron sputtering (GAMS) technique. The joint use of ball-cratering micro-abrasive wear test (BCMA) and nanoscratching (NN) test was proposed and carried out to evaluate the wear resistance of TiN films. The results showed an increase of 33.3% wear resistance in the FG TiN thin film, when compared with the HM TiN thin film. This result was justified by the higher resistance to nucleation and propagation of cracks and higher level of adhesion to the substrate by the FG TiN thin film, validated through the NN tests.

The present work investigated the formability of 1.1 mm thick sheets of 90/10 brass (UNS C22000) alloy obtained by two different process routes: continuous casting (CC) and semi-continuous casting (SCC). Formability was accessed using forming limit diagrams determined by two different methodologies: one suggested by the Commission of the European Communities (CEC, with grooved tensile samples to access the deep-drawing side of the diagram) and the standard Nakazima procedure. Final microstructures are equivalent, consisting of equiaxed recrystallized grains, with a smaller grain size for the CC sheet. In spite of this, the obtained FLDs suggest that both sheets have equivalent formabilities, with some slight better performance observed for the SCC sheet. This inconsistency was discussed in terms of the recrystallization texture observed for both sheets. Keywords: Materials processing, Brass, Forming limit diagram, Strain path effects, Texture

The purpose of this work is to present a ball-cratering equipment configuration to measure the coefficient of friction. Two load cells were used to measure, in real time, the “normal” and “tangential” forces during the experiments to calculate the coefficient of friction. Micro-abrasive wear tests were conducted on an AISI H10 tool steel specimen, with a ball of AISI 52100 steel and an abrasive slurry, prepared with SiC and distilled water; different values of normal force and sliding distance were defined for the wear experiments to investigate and validate the constructed machine. The results showed that due to test conditions, it was observed the occurrence of rolling abrasion. The equipment showed excellent functionality and reproducibility, in terms of formation of the wear craters and measurement of the coefficient of friction.

The abundance of iron and aluminum raw materials is often quoted as a strategic advantage of iron aluminides against other competing materials (not only stainless steels, but also nickel and titanium aluminides). These raw materials, however, are not only abundant in the form of ores in earth's crust, but also as scrap produced in the extensive technological activity associated with these base metals. The present work reports results of two prospective experiments designed for obtaining iron aluminides exclusively from readily available scrap (aluminum cans, carbon steel strips and stainless steel sheet metal forming residues, this last as a source of chromium and molybdenum). Two base alloys with nominal composition Fe–30Al–6Cr and different carbon contents were molten in a laboratory induction furnace with no atmosphere protection other than blowing Argon over the melt surface. The produced ingots were characterized concerning their microstructures and final composition, which allows estimating the incorporation efficiency of the alloying elements using this processing route. Oxidation tests at the temperature range of 800–1100 °C under air were performed to demonstrate that these alloys show similar behavior as the ones obtained using conventional processing routes. The results are discussed concerning the viability of this low-cost processing route for the industrial production of iron aluminides.