The Nb-Si based in-situ composite was produced by resistive sintering (RS) technique. In order to identify present phases, X-ray diffraction (XRD) analysis was used on the composite. XRD analysis revealed that the composite was composed of Nb solid solution (Nbss) and α-Nb5Si3 phases. The microstructure of the composite was characterized by using a scanning electron microscope (SEM). The energy-dispersive spectroscopy (EDS) was performed for the micro-analysis of the chemical species. SEM-EDS analyses show that the microstructure of composite consists of Nbss, Nb5Si3 and small volume fraction of Ti-rich Nbss phases. The micro hardness of constituent phases of the composite was found to be as 593±19 and 1408±33 Hv0.1, respectively and its relative density was % 98.54.

TiAl based intermetallics are widely used for structural applications in aviation, chemical engineering, automotive and sports equipment. In this study, the electrical resistance sintering (ERS) technology used in the production of gamma-TiAl intermetallics is based on the principle of applying pressure simultaneously with a high-density electric current. The purpose of this study was to investigate the cyclic oxidation resistance of Ti-44Al-3Mo and Ti-44Al-3Nb alloys (at.%) and the applicability of artificial neural network (ANN) modeling for the forecast of the oxidation behavior of these alloys. In order to obtain this aim, the alloys sintered by ERS were oxidized at 900°C for 360 h and then the oxidation behaviors of them are evaluated by plotting a graph between weight change as a function of time. The data collected after the oxidation experiments were used to construct the prediction models. The modelling results show that a good agreement between experimental results and prediction results was found. The oxidized alloys were characterized using XRD and SEM-EDS. The XRD patterns revealed the oxidation products are composed of TiO2 and Al2O3 oxides. SEM-EDS analysis indicated that the oxide scales of alloys are made up of a multilayered structure.