Scholarlink

<p>High-temperature oxidation critically affects the long-term performance of nickel-based alloys and heat-resistant steels, especially under welding thermal cycles. In this work, the oxidation behavior of tungsten inert gas (TIG)-welded 4715FC1 nickel-based superalloy/12Cr steel joints was systematically investigated at 560-650&#xa0;°C to elucidate the influence of microstructural heterogeneity and temperature. Results show that on the 4715FC1 base metal (BM), oxidation led to the formation of Cr<sub>2</sub>O<sub>3</sub> and NiCr<sub>2</sub>O<sub>4</sub> scales. In contrast, microstructural coarsening and the reduction of twin boundaries in the heat-affected zone (HAZ) degraded the integrity of the oxide film. The weld zone (WZ) exhibited improved oxidation resistance due to the generation of dense and adherent Cr<sub>2</sub>O<sub>3</sub> layers promoted by fine subgrains. At 620&#xa0;°C, the oxide scale thickened, accompanied by the transformation of the 12Cr steel side from a Fe<sub>3</sub>O<sub>4</sub>/Fe<sub>2</sub>O<sub>3</sub> bilayer to a MnFe<sub>2</sub>O<sub>4</sub>-containing multilayer structure, as well as local spallation in the HAZ. These findings clarify the temperature-dependent oxidation mechanisms of dissimilar metal joints and provide guidance for enhancing the high-temperature reliability of turbine rotor materials.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Oxidation Behavior of Different Microregions of 4715FC1/12Cr Dissimilar TIG-Welded Joints

  • 期刊论文

  • 发表日期：

    2025年12月8日

查看全文
  • Bomin Zhao,
  • Fuheng Nie,
  • Shuai Li,
  • Peng Li,
  • Liangliang Zhang,
  • Xin Jiang,
  • Yinchen Wang,
  • Honggang Dong

摘要

High-temperature oxidation critically affects the long-term performance of nickel-based alloys and heat-resistant steels, especially under welding thermal cycles. In this work, the oxidation behavior of tungsten inert gas (TIG)-welded 4715FC1 nickel-based superalloy/12Cr steel joints was systematically investigated at 560-650 °C to elucidate the influence of microstructural heterogeneity and temperature. Results show that on the 4715FC1 base metal (BM), oxidation led to the formation of Cr2O3 and NiCr2O4 scales. In contrast, microstructural coarsening and the reduction of twin boundaries in the heat-affected zone (HAZ) degraded the integrity of the oxide film. The weld zone (WZ) exhibited improved oxidation resistance due to the generation of dense and adherent Cr2O3 layers promoted by fine subgrains. At 620 °C, the oxide scale thickened, accompanied by the transformation of the 12Cr steel side from a Fe3O4/Fe2O3 bilayer to a MnFe2O4-containing multilayer structure, as well as local spallation in the HAZ. These findings clarify the temperature-dependent oxidation mechanisms of dissimilar metal joints and provide guidance for enhancing the high-temperature reliability of turbine rotor materials.