Abstract Pultrusion is a highly automated process for manufacturing structural composite elements, wherein the production rate depends on the pulling speed. This study analyzed the influence of pulling speed on the structural characteristics of pultruded glass fiber/epoxy-vinyl resin 75 × 75 × 6 mm L-shaped profiles. The profiles were pultruded at three pulling speeds: 200, 400, and 600 mm/min. After fabrication, the spring-in values of the fabricated profiles were measured; the profiles were examined under a microscope to identify and study their cracking; and the mechanical properties of the pultruded composite were determined. The spring-in was measured immediately after fabrication and then at intervals of two to three days over a 90-day period. The spring-in angle was found to increase with increments in the pulling speed. The profiles produced at the lower pulling speeds (200 and 400 mm/min) exhibited no significant differences in matrix cracking or mechanical characteristics. By comparison, at the high pulling speed (600 mm/min), wherein a large part of the profile is polymerized after exiting the die, the formation of delamination perpendicular to the matrix cracks was observed. Furthermore, at this pulling speed, there were increased variations in the strength and Young’s modulus values and decreased interlaminar shear strength.

中文翻译：

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拉拔速度对L型拉挤型材结构性能的影响

摘要 拉挤成型是一种高度自动化的结构复合元件制造工艺，其生产率取决于拉拔速度。本研究分析了拉拔速度对拉挤玻璃纤维/环氧树脂-乙烯基树脂 75 × 75 × 6 mm L 形型材结构特性的影响。型材以三种拉拔速度拉挤：200、400 和 600 毫米/分钟。制造完成后，测量所制造型材的弹力值；在显微镜下检查轮廓以识别和研究它们的裂纹；并测定了拉挤复合材料的力学性能。弹簧在制造后立即测量，然后在 90 天内每隔两到三天测量一次。发现弹入角随着牵引速度的增加而增加。在较低的拉拔速度（200 和 400 毫米/分钟）下产生的轮廓在基体开裂或机械特性方面没有显着差异。相比之下，在高拉速（600 毫米/分钟）下，其中大部分型材在离开模具后聚合，观察到垂直于基体裂纹的分层的形成。此外，在这种拉速下，强度和杨氏模量值的变化增加，层间剪切强度降低。观察到垂直于基体裂纹的分层的形成。此外，在这种拉速下，强度和杨氏模量值的变化增加，层间剪切强度降低。观察到垂直于基体裂纹的分层的形成。此外，在这种拉速下，强度和杨氏模量值的变化增加，层间剪切强度降低。