Impact of fiber‐type and autoclave‐treatment at different temperatures on the mechanical properties and interface performance of various fiber‐reinforced <scp>3D</scp>‐printed composites

Injection over‐molded short/continuous fiber reinforced composites are a unique class of materials for fabricating lightweight components having complex geometries in automotive manufacturing due to their higher specific mechanical properties, lower assembly cost, and short production cycle time. The influence of interface temperature on the low‐velocity impact response of short/continuous fiber‐reinforced polypropylene was experimentally investigated by varying the melt temperature. The over‐molded specimens fabricated at an interface temperature considerably higher than the melting point of polypropylene exhibited a 12% enhanced peak load with less impact damage compared with specimens over‐molded at a lower interface temperature. Optical analysis of impacted specimens over‐molded at lower interface temperature revealed interface debonding and insert delamination. Whereas insert delamination alone was observed for the specimens fabricated at higher interface temperature. The specimens over‐molded at high interface temperature exhibited less impact energy absorption and high compression strength after impact because of their strong interfacial adhesion.Highlights Impact energy absorption is less if melt temperature is high in injection over‐molding. Higher melt temperature enhances interface bonding by raising interface temperature. Interface debonding and insert delamination are the dominant impact failure modes. The compression strength after impact has increased with higher melt temperature. Impact and compression strength after impact is governed by the interfacial strength.

Section: Introductionmentioning

confidence: 99%

Effect of interface temperature on low‐velocity impact response of injection over‐molded short/continuous fiber reinforced polypropylene composites

Paramasivam,

Mallina,

Ramachandran

et al. 2023

“…Continuous carbon fiber (CCF) reinforced composites exhibited higher strength and modulus 19 . But CCF often has poor activity, which makes it difficult to form an effective interfacial bonding with the matrix, leading to poor mechanical properties 20 .…”

Section: Introductionmentioning

confidence: 99%

Interfacial performance and build orientation of 3D‐printed poly(ether‐ketone‐ketone) reinforced by continuous carbon fiber

Fan,

Zhou,

Zhang

et al. 2023

Continuous fiber reinforced thermoplastic composites (CFRTPCs) prepared by fused deposition modeling (FDM) have gained great attention for the benefit of preparing products without molds. However, unexpected debonding and defects are derived from insufficient impregnation between fiber and matrix in 3D‐printed samples, resulting in weak interfacial performance. In this work, a polyetherimide (PEI) sizing agent was used to improve the fiber‐matrix interfaces, and the interlaminar shear strength (ILSS) of the continuous carbon fiber reinforced poly(ether‐ketone‐ketone) composites was increased to 27.1 MPa, 12.4% higher than that of unmodified composite. Meanwhile, the performance of CFRTPCs is affected by process parameters in FDM. Build orientation of FDM was discussed and PEI weakened the anisotropy of samples' mechanical properties because the performance variation caused by build orientation decreased from 86.8% to 65.2%, which may be beneficial for the forming freedom of in situ impregnated FDM. The addition of PEI makes sense to apply in situ impregnated FDM in high‐tech fields.Highlights CCF/PEKK composites were prepared by in situ impregnated FDM. ILSS of flat‐oriented CCF/PEKK was 86.8% higher than that of on‐edge. 5 wt% PEI sizing agent promoted adhesion of CCF and PEKK to obtain the best mechanical properties. PEI weakened the anisotropy of samples' mechanical properties, which was conducive to forming freedom.

A new mechanism of mechanical reinforcement for 3D printing CF/PA12 composite based on microwave treatment

Zhang,

Zhi,

et al. 2024

Although 3D printing technology has been widely applied in fabrication of polymer composite, yet, it still exhibits low mechanical performance, restricting its application in structural materials. Herein, a new 3D printing polymer composite composed of carbon fiber and polyamide12 (PA12) is fabricated and subsequently treated by microwave treatment. It is found that the tensile strength and modulus of 3D printing CF/PA12 composite with microwave treatment are improved by 23.8% and 10.2% compared with the original specimen, respectively. Moreover, a new mechanism of mechanical reinforcement is investigated and proposed by nanoindentation and 3D X‐ray computed tomography. The work does not only confirm formation of 3D printing CF/PA12 composite with good mechanical properties, but also proposes a new mechanism of microwave treatment effect on 3D printing polymer composite based on carbon fiber.Highlights A new 3D printing CF/PA12 composite based on microwave treatment is developed. The 3D printing composite exhibits good mechanical properties. A new mechanism of mechanical reinforcement is proposed.