Scholarlink

<p>Polymer extrusion additive manufacturing (AM) has developed into a key technology for fabricating functional components. However, its widespread adoption is hindered by the inherent anisotropy resulting from inadequate interlayer adhesion, which compromises mechanical integrity along the build direction. Addressing this challenge, an innovative rheological control technique utilizing extrusion nozzle rotation in material extrusion AM is proposed to enhance interlayer bonding. This method exploits the shear-thinning behavior of pseudoplastics, such as Polylactic Acid (PLA) to locally modulate viscosity and improve adhesion between layers. A comprehensive numerical analysis revealed that the shearing effect induced by nozzle rotation significantly reduces the viscosity of the extrudate shell. At 200 RPM, shell viscosity decreased by 7.5%, facilitating enhanced interlayer adhesion. Mechanical validation using flatwise tensile testing method demonstrated substantial improvements in apparent interlayer adhesion, with increases of 25% and 12.7% at extrusion temperature of 165&#xa0;°C and 185&#xa0;°C, respectively. The observed reduction in adhesion enhancement at higher temperatures is attributed to the dominant influence of thermal effects over shear-induced viscosity reduction. These findings highlight the potential of nozzle rotation for mitigating anisotropic effect in material extrusion AM, paving the way for enhanced mechanical performance in printed components.</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

Interlayer Adhesion Enhancement of Material Extrusion Additive Manufacturing: A Rheological Approach

  • 期刊论文

  • 发表日期：

    2026年3月12日

查看全文
  • Hussam H. Noor,
  • John P. Coulter

摘要

Polymer extrusion additive manufacturing (AM) has developed into a key technology for fabricating functional components. However, its widespread adoption is hindered by the inherent anisotropy resulting from inadequate interlayer adhesion, which compromises mechanical integrity along the build direction. Addressing this challenge, an innovative rheological control technique utilizing extrusion nozzle rotation in material extrusion AM is proposed to enhance interlayer bonding. This method exploits the shear-thinning behavior of pseudoplastics, such as Polylactic Acid (PLA) to locally modulate viscosity and improve adhesion between layers. A comprehensive numerical analysis revealed that the shearing effect induced by nozzle rotation significantly reduces the viscosity of the extrudate shell. At 200 RPM, shell viscosity decreased by 7.5%, facilitating enhanced interlayer adhesion. Mechanical validation using flatwise tensile testing method demonstrated substantial improvements in apparent interlayer adhesion, with increases of 25% and 12.7% at extrusion temperature of 165 °C and 185 °C, respectively. The observed reduction in adhesion enhancement at higher temperatures is attributed to the dominant influence of thermal effects over shear-induced viscosity reduction. These findings highlight the potential of nozzle rotation for mitigating anisotropic effect in material extrusion AM, paving the way for enhanced mechanical performance in printed components.