Preparation of Polyimide Nanofiber Membranes and Interlaminar Toughness Investigation of Their Toughened Composites

NANO ◽  
2021 ◽  
Author(s):  
Hailiang Wu ◽  
Chao Yu ◽  
Yuan Chen ◽  
Chao Yan ◽  
Xiaoqing Wu ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Fiber Diameter ◽  
Reinforced Composites ◽  
Interlaminar Fracture Toughness ◽  
Fiber Reinforced ◽  
Water Contact ◽  
Interlaminar Fracture ◽  
Electrospinning Method ◽  
Ft Ir ◽  
Nanofiber Membranes

Interlaminar delamination and brittle fracture of matrix have been a dilemma that fiber-reinforced composites have been faced with. Herein, the polyimide (PI) nanofiber-toughened glass fiber fiber-reinforced epoxy composites were prepared by electrospinning method and subsequent vacuum assistant resin transfer molding. The effect of spinning parameters including PI concentration, applied voltage, collector distance, jet speed and ambient humidity on the resultant fiber diameter and its distribution was systematically evaluated. The surface properties of obtained PI nanofibers were characterized by FT-IR, TG-DSC and water contact angle. The effect of PI concentration on tensile strength of PI membranes was also studied. The mode I (G[Formula: see text] and mode II (G[Formula: see text] interlaminar fracture toughness were measured. The results indicated that GIc and GIIc increased by 127.69% and 85.33%. The improvement of interlaminar fracture toughness may be attributed to the bridging effect of PI nanofibers.

scholarly journals Mode I Interlaminar Fracture Toughness Analysis of Co-Bonded and Secondary Bonded Carbon Fiber Reinforced Composites Joints

2018 ◽  
Vol 20 (suppl 2) ◽  
pp. 873-882 ◽  
Author(s):  
Camila Belo Gomes Brito ◽  
Rita de Cássia Mendonça Sales Contini ◽  
Ricardo Francisco Gouvêa ◽  
Arthur Scaglioni de Oliveira ◽  
Mariano Andrés Arbelo ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Carbon Fiber ◽  
Fiber Reinforced Composites ◽  
Mode I ◽  
Reinforced Composites ◽  
Interlaminar Fracture Toughness ◽  
Fiber Reinforced ◽  
Interlaminar Fracture ◽  
Carbon Fiber Reinforced Composites ◽  
Carbon Fiber Reinforced

scholarly journals Woven Glass Fiber Composites with Aligned Carbon Nanotube Sheet Interlayers

2016 ◽  
Vol 2016 ◽  
pp. 1-9 ◽  
Author(s):  
Hardik Bhanushali ◽  
Philip D. Bradford
Keyword(s):  
Fracture Toughness ◽  
Glass Fiber ◽  
Mode I ◽  
Mode Ii ◽  
Interlaminar Fracture Toughness ◽  
Fiber Reinforced ◽  
Interlaminar Fracture ◽  
Glass Fiber Reinforced ◽  
Short Beam ◽  
Woven Glass Fiber

This investigation describes the design, fabrication, and testing of woven glass fiber reinforced epoxy matrix laminates with aligned CNT sheets integrated between plies in order to improve the matrix dominated through thickness properties such as the interlaminar fracture toughness at ply interfaces. Using aligned CNT sheets allows for a concentration of millimeter long CNTs at the most likely point of laminate failure. Mode I and Mode II interlaminar fracture toughness of various CNT modified samples were investigated using double cantilever beam (DCB) and end notched flexure (ENF) experiments, respectively. Short beam strength (SBS) and in-plane tensile properties of the CNT modified samples were also investigated. Moderate improvement was observed in Mode I and Mode II fracture toughness at crack initiation when aligned CNT sheets with a basis weight of 0.354 g/m2were used to modify the ply interface. No compromise in the in-plane mechanical properties of the laminate was observed and very little improvement was observed in the shear related short beam strength of the CNT modified laminates as compared to the control samples. Integration of aligned CNT sheets into the composite laminate imparted in-plane and through thickness electrical properties into the nonconductive glass fiber reinforced epoxy composite laminates.

Interlaminar Fracture Toughness of Composite Laminate with Splicing Plies

2011 ◽  
Vol 194-196 ◽  
pp. 1697-1702
Author(s):  
Li Liang ◽  
Pu Rong Jia ◽  
Gui Qiong Jiao
Keyword(s):  
Fracture Toughness ◽  
Composite Laminates ◽  
Tensile Testing ◽  
Mode Ii ◽  
Interlaminar Fracture Toughness ◽  
Fiber Reinforced ◽  
Interlaminar Fracture ◽  
Mode Ii Fracture ◽  
Mode Ii Fracture Toughness ◽  
Delamination Failure

Delamination is one of the important damage modes in the fiber-reinforced composite laminates. The interlaminar fracture toughness is the key parameter in delamination failure analysis of composites. The stress analysis by a finite element modeling has shown that the shear stress is very large near the ply splicing area. So the delamination failure is mainly dependent on the mode II fracture toughness. A new way of loading in tensile testing is proposed for the measurement of mode II fracture toughness. Specific specimen with splicing plies has been designed and used for the experiment. Testing study on the carbon-fiber-reinforced laminate with ply splicing was performed. Steady crack propagation has been seen by the tensile testing of the specimen. Mode II fracture toughness GIIC of the laminate has been determined by the experiment data analysis. The experiment and numerical analysis shows that the tensile testing for the measurement of mode II interlaminar fracture toughness is feasible.

Sign in / Sign up

Export Citation Format

Share Document