Analysis of vibration characteristics and damping performance of metal–rubber components under different injection molding flow-induced structural features


Yazıcı M., Kurt G., Polat A., Koçak S., Deliktaş B.

6th International Conference on Materials Design and Applications 2026 (MDA2026), Porto, Portekiz, 2 - 03 Temmuz 2026, cilt.1, sa.1, ss.163, (Özet Bildiri)

  • Yayın Türü: Bildiri / Özet Bildiri
  • Cilt numarası: 1
  • Basıldığı Şehir: Porto
  • Basıldığı Ülke: Portekiz
  • Sayfa Sayıları: ss.163
  • Bursa Uludağ Üniversitesi Adresli: Evet

Özet

Metal-rubber and polymer-based composite isolators, widely used for shock and vibration isolation in

aerospace, automotive, and industrial machinery applications, offer high energy-damping capacity due

to both their viscoelastic properties and dry-friction mechanisms. The mechanical and damping performance

of these composite components heavily depends on the internal microstructures formed during

manufacturing. The objective of this study is to investigate the effects of "flow-induced structural features"

imposed on the polymer/elastomer phase during the injection molding process on the nonlinear

vibration characteristics and damping performance of metal-rubber components.

During the filling of the mold cavity in the injection molding process, "fountain flow," combined with

shear and stretching flows, directly affects the molecular structure and fiber orientations (if applicable)

of the material, generating a skin-shear-core morphology. Within the scope of this research, test specimens

with different flow-induced orientations and structural features (e.g., weld lines) were produced

by varying process parameters, including injection speed, melt temperature, and packing pressure. The

dynamic properties of the metal-rubber and elastomer structure were characterized via Dynamic Mechanical

Analysis (DMA) and hysteresis loop tests under various vibration frequencies, amplitudes, and

preloads.

The findings indicate that the thickness of the flow-aligned frozen skin layer and the molecular orientation

are decisive factors in the material's storage and loss moduli. It was determined that flow-induced

morphological optimization enhances the viscoelastic energy dissipation (loss factor - tan delta) of the

elastomer. In addition, the metal-rubber network exhibits strong nonlinear softening with vibration amplitude

and maximizes damping performance through dry sliding friction between the helical wires. In

conclusion, this study demonstrates that controlling flow mechanisms and structural orientations during

injection molding plays a critical role in improving the dynamic stiffness and energy-damping capacities

of metal-rubber hybrid isolators.

Acknowledgement: The authors would like to thank the Scientific and Technological Research Council

of Turkey (TÜBİTAK) for their support within the scope of the International Cornet project OPTIMOLD

(Project No: 123N452) and the SME user committee member, YAMAS Rubber & Metal Solutions,

for providing the part information used in this research.