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<p>The long-term oxidation behavior of the HAYNES<sup>®</sup> 282<sup>®</sup> superalloy was systematically investigated in air at temperatures ranging from 800 to 950&#xa0;°C for durations of up to 720&#xa0;h. The oxide phases that developed on the surface of the alloy were characterized using X-ray diffraction and energy-dispersive X-ray spectroscopy (EDS). The residual stress within the Cr<sub>2</sub>O<sub>3</sub> layer was assessed utilizing the average X-ray strain method. The primary oxide phase was identified as rhombohedral Cr<sub>2</sub>O<sub>3</sub>, with secondary phases including rutile-TiO<sub>2</sub>, spinel-MnCr<sub>2</sub>O<sub>4</sub>, and perovskite CoTiO<sub>3</sub>. The thickness of the external oxide layer increased with both oxidation temperature and time, adhering to parabolic kinetics. EDS mapping indicated the dispersion of Al-rich and Ti-rich oxides internally, suggesting the precipitation of Al<sub>2</sub>O<sub>3</sub> and TiO<sub>2</sub> beneath the external Cr<sub>2</sub>O<sub>3</sub> layer. The activation energy for the long-term oxidation of HAYNES<sup>®</sup> 282<sup>®</sup> was calculated to be 272.5 ± 15.0&#xa0;kJ&#xa0;mol<sup>−1</sup>. The total residual stresses within the Cr<sub>2</sub>O<sub>3</sub> phase measured at room temperature were found to be entirely compressive. The calculated intrinsic residual stress associated with Cr<sub>2</sub>O<sub>3</sub> growth at 800&#xa0;°C exhibited a transition from tensile to compressive, whereas at 950&#xa0;°C, it remained tensile. The evolution of intrinsic stress in relation to oxidation time, temperature, and scale thickness was discussed in the context of the crystallite coalescence model and the Pilling–Bedworth ratio.</p>

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Evolution of Oxide Phases and Residual Stress in HAYNES® 282® Superalloy During Long-Term High-Temperature Oxidation

  • 期刊论文

  • 出版模式：

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  • 发表日期：

    2025年6月12日

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  • Hsiao-Ming Tung,
  • Ting-Li Chen,
  • Kuan-Che Lan

摘要

The long-term oxidation behavior of the HAYNES® 282® superalloy was systematically investigated in air at temperatures ranging from 800 to 950 °C for durations of up to 720 h. The oxide phases that developed on the surface of the alloy were characterized using X-ray diffraction and energy-dispersive X-ray spectroscopy (EDS). The residual stress within the Cr2O3 layer was assessed utilizing the average X-ray strain method. The primary oxide phase was identified as rhombohedral Cr2O3, with secondary phases including rutile-TiO2, spinel-MnCr2O4, and perovskite CoTiO3. The thickness of the external oxide layer increased with both oxidation temperature and time, adhering to parabolic kinetics. EDS mapping indicated the dispersion of Al-rich and Ti-rich oxides internally, suggesting the precipitation of Al2O3 and TiO2 beneath the external Cr2O3 layer. The activation energy for the long-term oxidation of HAYNES® 282® was calculated to be 272.5 ± 15.0 kJ mol−1. The total residual stresses within the Cr2O3 phase measured at room temperature were found to be entirely compressive. The calculated intrinsic residual stress associated with Cr2O3 growth at 800 °C exhibited a transition from tensile to compressive, whereas at 950 °C, it remained tensile. The evolution of intrinsic stress in relation to oxidation time, temperature, and scale thickness was discussed in the context of the crystallite coalescence model and the Pilling–Bedworth ratio.