Mechanical Performance and Structural Integrity of 3D-Printed Polylactic Acid in Tensile Testing: Influence of Hole Fabrication Technique and Process Parameters


Kalyoncu E., Temiztaş B. A., BOLAT B., Kaya A. C.

Latin American Journal of Solids and Structures, cilt.23, sa.2, 2026 (SCI-Expanded, Scopus) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 23 Sayı: 2
  • Basım Tarihi: 2026
  • Doi Numarası: 10.1590/1679-7825/e8775
  • Dergi Adı: Latin American Journal of Solids and Structures
  • Derginin Tarandığı İndeksler: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Compendex, Directory of Open Access Journals
  • Anahtar Kelimeler: Drilled vs. Printed Holes, Fused Filament Fabrication (FFF), PLA, Stress Concentration Factor, Tensile Strength
  • Yıldız Teknik Üniversitesi Adresli: Evet

Özet

This study presents a systematic investigation of the tensile behavior of FFF-printed PLA specimens, with a specific emphasis on the role of hole fabrication methods—post-drilled versus integrated printed holes—on structural integrity. Unlike prior works that primarily addressed raster orientation and infill effects, this research isolates the influence of hole manufacturing techniques under standardized ASTM D638 and D5766 testing. Stress concentration factors (Kt) were calculated using classical analytical expressions, and their limitations for anisotropic FFF parts are acknowledged and further discussed in the Results and Discussion section. The results revealed that, although raster angle and infill density affected overall strength, the decisive factor was the method of hole generation: post-drilled holes consistently outperformed printed-hole counterparts in tensile resistance and failure behavior. Microscopic analysis confirmed that printed holes introduced interlayer misalignment and shell–infill discontinuities, accelerating crack initiation. These findings demonstrate that hole geometry alone is insufficient to guarantee mechanical reliability, and that the fabrication method of stress concentrators must be considered a critical design parameter in FFF applications.