S. Geng, J. Zhu, Z. Lu, Tennessee Technological University, Cookeville, TN
Ni-base alloys have been widely used at high temperature due to their oxidation or corrosion resistance; chromia-forming Ni-base alloys are candidate interconnect materials for solid oxide fuel cell (SOFC) at intermediate temperature. This paper investigated oxidation behavior of the Haynes 242 alloy in air at 700°ãC, 800°ãC and 900°ãC. Oxidation kinetics was determined using a thermal balance and the surface morphology and cross-section of oxidized specimens were examined using scanning electron microscopy with an energy-dispersive X-ray analysis attachment (SEM/EDX). Phase structure of oxide formed on this alloy was characterized by X-Ray diffraction (XRD) and area specific resistance was measured using a DC four-point method. The oxidation mechanism of this alloy and its potential as interconnect material was discussed.
Key words: oxidation, interconnect, Ni-based, alloy, high temperature
Summary: This paper characterized oxidation behavior of the Haynes 242 alloy in air at 700°C, 800°C and 900°C using thermal balance. Oxidation kinetics of this alloy was studied. Surface morphologies, cross-section and phase structure of oxidized specimens were examined using scanning electron microscopy with an energy-dispersive X-ray analysis attachment (SEM/EDX) and X-Ray diffraction (XRD). Oxidation mechanism was discussed.