Scholarlink

<p>In this study, the gas-nitriding behavior of a high Co–Ni secondary hardening ultra-high-strength steel (AerMet100) steel in pure ammonia at 480&#xa0;°C in the medium-pressure range of 0.1–0.7&#xa0;MPa was investigated. The phase composition and microstructure of the nitriding layer were analyzed using optical microscopy, scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. The relationships among the pressure and nitrogen concentration, penetration depth, surface layer hardness, and test steel microstructure were discussed. The results show that compared with conventional gas nitriding, pressurized gas nitriding can significantly improve the nitriding efficiency of A100 steel. The depth of the nitrided layer formed after pressurized gas nitriding at 0.5&#xa0;MPa is approximately 1.5-fold greater than that of the layer formed at atmospheric pressure. The pressurized gas-nitriding layer of A100 steel is mainly composed of <i>α</i>-Fe and <i>γ</i>′-Fe<sub>4</sub>N. With increasing nitriding pressure, the hardness of the nitriding layer first increased and then decreased. At 0.5&#xa0;MPa nitriding pressure, the specimen surface was the hardest, reaching 1206 HV. Increasing the nitriding pressure effectively inhibited NH<sub>3</sub> decomposition and increased the nitrogen potential, thereby effectively promoting the rapid thickening of the nitrided layer of A100 steel.</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

Study on the Pressurized Gas-Nitriding Characteristics of High Co–Ni Secondary Hardening Ultra-High-Strength Steel

  • 期刊论文

  • 发表日期：

    2025年11月25日

查看全文
  • Haonan Liu,
  • Rongbin Li,
  • Yong Li,
  • Chunxu Wang,
  • Zhiqing Lv,
  • Bo Wang,
  • Wantang Fu

摘要

In this study, the gas-nitriding behavior of a high Co–Ni secondary hardening ultra-high-strength steel (AerMet100) steel in pure ammonia at 480 °C in the medium-pressure range of 0.1–0.7 MPa was investigated. The phase composition and microstructure of the nitriding layer were analyzed using optical microscopy, scanning electron microscopy, X-ray diffraction, and transmission electron microscopy. The relationships among the pressure and nitrogen concentration, penetration depth, surface layer hardness, and test steel microstructure were discussed. The results show that compared with conventional gas nitriding, pressurized gas nitriding can significantly improve the nitriding efficiency of A100 steel. The depth of the nitrided layer formed after pressurized gas nitriding at 0.5 MPa is approximately 1.5-fold greater than that of the layer formed at atmospheric pressure. The pressurized gas-nitriding layer of A100 steel is mainly composed of α-Fe and γ′-Fe4N. With increasing nitriding pressure, the hardness of the nitriding layer first increased and then decreased. At 0.5 MPa nitriding pressure, the specimen surface was the hardest, reaching 1206 HV. Increasing the nitriding pressure effectively inhibited NH3 decomposition and increased the nitrogen potential, thereby effectively promoting the rapid thickening of the nitrided layer of A100 steel.