Scholarlink

<p>Super duplex stainless steels (SDSSs) are widely used in offshore, marine, and chemical processing industries due to their excellent combination of high strength and corrosion resistance; however, improper heat input during welding can disturb the ferrite–austenite phase balance and consequently degrade mechanical performance. In gas tungsten arc welding (GTAW) of SDSS, precise control and monitoring of heat input are essential to maintain the desired phase balance and to prevent the formation of undesirable intermetallic phases. This study investigates the influence of controlled heat input on phase balance, microstructural evolution, and mechanical properties of UNS S32750 GTAW-welded SDSS, with the objective of identifying an optimal thermal input window for reliable joint performance. The weld joints were created under three heat input conditions (low, medium, and high) with varying welding parameters including variation of welding current, voltage, and travel speed. Microstructural characterization was performed using optical microscopy and fractographic analysis, while mechanical behavior was evaluated through tensile and hardness testing. The experimental results demonstrate that the weld metal zone exhibited maximum tensile strength (648&#xa0;MPa) and hardness (265 HV) under the medium heat input condition, indicating an optimal balance between ferrite–austenite phase distribution and thermal control. Fractographic analysis revealed brittle or mixed-mode fracture characteristics at medium heat input, whereas predominantly ductile fracture was observed under optimized welding parameters. The results indicate the importance of medium heat input during the provision of good weld quality and dependable mechanical properties on GTAW-welded components of the super duplex stainless 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

Influence of Heat Input on Phase Balance, Microstructural Evolution, and Mechanical Performance of Super Duplex Stainless Steel Welded by Gas Tungsten Arc Welding

  • 期刊论文

  • 发表日期：

    2026年4月7日

查看全文
  • Rajeev Kumar,
  • Anant Prakash Agrawal,
  • Manish Maurya,
  • Shahazad Ali,
  • Manish Kumar Giri,
  • Amit Kumar,
  • Nagendra Kumar Maurya

摘要

Super duplex stainless steels (SDSSs) are widely used in offshore, marine, and chemical processing industries due to their excellent combination of high strength and corrosion resistance; however, improper heat input during welding can disturb the ferrite–austenite phase balance and consequently degrade mechanical performance. In gas tungsten arc welding (GTAW) of SDSS, precise control and monitoring of heat input are essential to maintain the desired phase balance and to prevent the formation of undesirable intermetallic phases. This study investigates the influence of controlled heat input on phase balance, microstructural evolution, and mechanical properties of UNS S32750 GTAW-welded SDSS, with the objective of identifying an optimal thermal input window for reliable joint performance. The weld joints were created under three heat input conditions (low, medium, and high) with varying welding parameters including variation of welding current, voltage, and travel speed. Microstructural characterization was performed using optical microscopy and fractographic analysis, while mechanical behavior was evaluated through tensile and hardness testing. The experimental results demonstrate that the weld metal zone exhibited maximum tensile strength (648 MPa) and hardness (265 HV) under the medium heat input condition, indicating an optimal balance between ferrite–austenite phase distribution and thermal control. Fractographic analysis revealed brittle or mixed-mode fracture characteristics at medium heat input, whereas predominantly ductile fracture was observed under optimized welding parameters. The results indicate the importance of medium heat input during the provision of good weld quality and dependable mechanical properties on GTAW-welded components of the super duplex stainless steel.