The oxidation resistance optimization of titanium carbide/hastelloy (Ni-based alloy) composites applied for intermediate-temperature solid oxide fuel cell interconnects

摘要

Titanium carbide/hastelloy (TiC/hastelloy) composites are potential candidates for intermediatetemperature solid oxide fuel cell interconnects. In this work, TiC/hastelloy composites with suitable coefficient of thermal expansion are fabricated by in-situ reactive infiltration method, and their properties are optimized by adjusting TiC particle size (dTiC). The oxidation process of TiC/hastelloy composites is comprehensive performance of TiC and Ni-Cr alloy and determined by outward diffusion of Ti and Ni atoms and internal diffusion of O-2. The oxidation resistance of composites could be improved by the decrease of dTiC through accelerating the formation of continuous and dense TiO2/Cr2O3 oxide scale. Moreover, the electrical conductivity of composites at 800 degrees C for 100 h is 5600-7500 S cm(-1) and changes little with the prolongation of oxidation time. The decrease of dTiC is favorable for the properties optimization, and composites with 2.16 mu m TiC exhibits good integrated properties. (C) 2017 Elsevier B. V. All rights reserved.