Scholarlink

<p>Wire arc additive manufacturing is increasingly adopted for producing large stainless steel components for structural and wear-critical applications in marine, chemical processing, and energy sectors; however, variations in microstructure and wear behavior across the build height remain a major concern. This study investigates the microstructural evolution, hardness distribution, and tribological performance of wire arc additively manufactured 304L stainless steel. Microstructural analysis revealed columnar austenitic grains containing delta ferrite, with a relatively refined morphology near the substrate due to rapid heat extraction and progressively coarser features toward the top layers as a result of heat accumulation. The microhardness decreased from approximately 182 HV at the bottom region to about 148 HV at the top region, corresponding to an overall reduction of nearly 19%. This hardness reduction was accompanied by an increase in ferrite content from 3.3 to 6.26, indicating the influence of thermal cycling and microstructural coarsening. Tribological testing showed that the wear rate increased linearly with applied load, consistent with Archard’s wear relationship. Specimens tested in the vertical orientation exhibited approximately 8-12% lower wear rates than those tested in the horizontal orientation. The vertical orientation showed mild abrasive wear and stable surface deformation, whereas the horizontal orientation exhibited deeper grooves and pronounced delamination at higher loads. The coefficient of friction remained lower and more stable for the vertical orientation, particularly at lower loads, while higher and more fluctuating values were observed for the horizontal orientation. Scanning electron microscopy of worn surfaces confirmed a transition from mild abrasive wear at low loads to severe adhesive and delamination-dominated wear at higher loads. This study demonstrates that build orientation plays a critical role in governing hardness retention and wear resistance in wire arc additively manufactured 304L stainless steel, with vertically oriented builds offering superior tribological performance for load-bearing applications.</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

Investigation of Microstructural and Tribological Characteristic of WAAM-Fabricated 304L Stainless Steel

  • 期刊论文

  • 发表日期：

    2026年3月6日

查看全文
  • Mandeep Kumar,
  • Sachin Rathore,
  • Gaurav Sharma,
  • Hemant Kumar,
  • Ratnesh Kumar Raj Singh

摘要

Wire arc additive manufacturing is increasingly adopted for producing large stainless steel components for structural and wear-critical applications in marine, chemical processing, and energy sectors; however, variations in microstructure and wear behavior across the build height remain a major concern. This study investigates the microstructural evolution, hardness distribution, and tribological performance of wire arc additively manufactured 304L stainless steel. Microstructural analysis revealed columnar austenitic grains containing delta ferrite, with a relatively refined morphology near the substrate due to rapid heat extraction and progressively coarser features toward the top layers as a result of heat accumulation. The microhardness decreased from approximately 182 HV at the bottom region to about 148 HV at the top region, corresponding to an overall reduction of nearly 19%. This hardness reduction was accompanied by an increase in ferrite content from 3.3 to 6.26, indicating the influence of thermal cycling and microstructural coarsening. Tribological testing showed that the wear rate increased linearly with applied load, consistent with Archard’s wear relationship. Specimens tested in the vertical orientation exhibited approximately 8-12% lower wear rates than those tested in the horizontal orientation. The vertical orientation showed mild abrasive wear and stable surface deformation, whereas the horizontal orientation exhibited deeper grooves and pronounced delamination at higher loads. The coefficient of friction remained lower and more stable for the vertical orientation, particularly at lower loads, while higher and more fluctuating values were observed for the horizontal orientation. Scanning electron microscopy of worn surfaces confirmed a transition from mild abrasive wear at low loads to severe adhesive and delamination-dominated wear at higher loads. This study demonstrates that build orientation plays a critical role in governing hardness retention and wear resistance in wire arc additively manufactured 304L stainless steel, with vertically oriented builds offering superior tribological performance for load-bearing applications.