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1.
The objective of this work is to investigate the interlaminar fracture and damage behavior of glass fiber reinforced polymer (GFRP) woven laminates loaded in a mixed-mode bending (MMB) apparatus at cryogenic temperatures. The finite element analysis (FEA) is used to determine the mixed-mode interlaminar fracture toughness of MMB specimen at room temperature (RT), liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). A FEA coupled with damage is also employed to study the damage distributions within the MMB specimen and to examine the effect of damage on the mixed-mode energy release rate. The technique presented can be efficiently used for characterization of mixed-mode interlaminar fracture and damage behavior of woven laminate specimens at cryogenic temperatures. 相似文献
2.
Summary Interlaminar fracture and damage behavior of glass fiber reinforced polymer (GFRP) woven laminates at cryogenic temperatures
is investigated for end notched flexure (ENF) pure Mode II configuration. The corrected beam theory (CBT) and finite element
analysis (FEA) are used to calculate the Mode II interlaminar fracture toughness of ENF specimen at room temperature (RT),
liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). A FEA coupled with damage is also employed to study
the damage distributions within the specimen and to examine the effect of damage on the Mode II energy release rate. The numerical
results show that damage occurs at the matrix and causes a decrease in the energy release rate. The technique presented can
be efficiently used for the characterization of cryogenic Mode II interlaminar fracture and damage behavior of woven laminate
ENF specimens. 相似文献
3.
Masaya Miura Yasuhide Shindo Tomo Takeda Fumio Narita 《Applied Composite Materials》2013,20(4):587-599
We characterize the combined Mode I and Mode III delamination fracture behavior of woven glass fiber reinforced polymer (GFRP) composite laminates at cryogenic temperatures. The eight-point bending plate (8PBP) tests were conducted at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) using a new test fixture. A three-dimensional finite element analysis was also performed to calculate the energy release rate distribution along the delamination front, and the delamination fracture toughnesses were evaluated for various mixed-mode I/III ratios. Furthermore, the microscopic examinations of the fracture surfaces were carried out with scanning electron microscopy (SEM), and the mixed-mode I/III delamination fracture mechanisms in the woven GFRP laminates at cryogenic temperatures were assessed. The fracture properties were then correlated with the observed characteristics. 相似文献
4.
Yasuhide Shindo Masaya MiuraTomo Takeda Nozomi SaitoFumio Narita 《Composites Science and Technology》2011,71(5):647-652
This paper investigates the fatigue delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates under mixed-mode I/II conditions at cryogenic temperatures. Fatigue delamination tests were performed with the mixed-mode bending (MMB) test apparatus at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K), in order to obtain the delamination growth rate as a function of the range of the energy release rate, and the dependence of the delamination growth behavior on the temperature and the mixed-mode ratio of mode I and mode II was examined. The energy release rate was evaluated using three-dimensional finite element analysis. The fractographic examinations by scanning electron microscopy (SEM) were also carried out to assess the mixed-mode fatigue delamination growth mechanisms in the woven GFRP laminates at cryogenic temperatures. 相似文献
5.
This paper presents the experimental and numerical characterization of the interlaminar shear failure of hybrid composite laminates at cryogenic temperatures. Cryogenic short beam shear tests were performed on hybrid laminates consisting of woven glass fiber reinforced polymer (GFRP) composites and polyimide films to evaluate their interlaminar shear strength. Microscopic observations of damage accumulation and failure mechanisms were also made on failed specimens. In addition, a progressive damage analysis was conducted to predict the initiation and growth of damage in the specimens, and the interlaminar shear strength was determined from the maximum shear stress in the failure region. The damage effect on the interlaminar shear properties of hybrid laminates at cryogenic temperatures was examined based on the experimental and numerical results. 相似文献
6.
《低温学》2013
We investigate the cryogenic delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates under mixed-mode II/III fatigue loading. Fatigue delamination tests were conducted with six-point bending plate (6PBP) specimens at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K), and the delamination growth rate data for various mixed-mode ratios of Modes II and III were obtained. The energy release rate was evaluated using the three-dimensional finite element method. In addition, the fatigue delamination growth mechanisms were characterized by scanning electron microscopic observations of the specimen fracture surfaces. 相似文献
7.
This paper investigates the through-thickness tensile behavior of woven glass fiber reinforced polymer (GFRP) composite laminates at cryogenic temperatures. Tensile tests were carried out with cross specimens at room temperature and liquid nitrogen temperature (77 K), and the through-thickness elastic and strength properties of the woven GFRP laminates were evaluated. The failure characteristics of the woven GFRP laminates were also studied by optical and laser scanning microscopy observations. A three-dimensional finite element analysis was performed to calculate the stress distributions in the cross specimens, and the failure conditions of the specimens were examined. It is found that the cross specimen is suitable for the cryogenic through-thickness tensile characterization of laminated composite materials. In addition, the through-thickness Young's modulus of the woven GFRP composite laminates is dominated by the properties of the matrix polymer in the given temperature, while the tensile strength is characterized by both, the fiber to matrix interface energy and the cohesion energy of the matrix polymer. 相似文献
8.
This paper reports the cryogenic interlaminar shear properties of composite insulation systems for the superconducting magnet coils in the International Thermonuclear Experimental Reactor (ITER). Short beam shear tests were performed at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) on three insulation systems consisting of woven glass fiber reinforced plastic (GFRP) composites with different polymer resins and polyimide films, and the dependence of their apparent interlaminar shear strength on the temperature and the polymer resins was discussed. A detailed observation of failed specimens was made to verify the failure mechanisms. Insulation systems subjected to gamma irradiation at room temperature were also considered, and the effect of irradiation on the cryogenic interlaminar shear properties was examined. 相似文献
9.
Yasuhide Shindo Tomo Takeda Fumio Narita Nozomi Saito Shinya Watanabe Kazuaki Sanada 《Composites Science and Technology》2009,69(11-12):1904-1911
The purpose of this research is to characterize the cryogenic delamination growth behavior in woven glass fiber reinforced polymer (GFRP) composite laminates subjected to Mode II fatigue loading. Mode II fatigue delamination tests were performed at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) using the four-point bend end-notched flexure (4ENF) test method, and the delamination growth rate data for the woven GFRP laminates were obtained. The energy release rate range was determined by the finite element method. Microscopic examinations of the specimen sections and fracture surfaces were also carried out. The present results are discussed to obtain an understanding of the fatigue delamination growth mechanisms in the woven GFRP laminates under Mode II loading at cryogenic temperatures. 相似文献
10.
This paper describes an experimental and analytical study on fracture and damage behavior of GFRP woven laminates at cryogenic temperatures. CT (compact tension) tests were carried out at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K) to evaluate the critical values of the fracture mechanics parameters. During the CT tests, AE (acoustic emission) method was implemented. AE signals can identify the critical load at which gross failure occurs. A FEA (finite element analysis) was also applied to calculate the fracture mechanics parameters. The failure criteria (Hoffman criterion and maximum strain criterion) or the damage variable based on the continuum damage mechanics was incorporated into the model to interpret the experimental measurements and to study the damage distributions within the specimen. Several methods of calculating J-integral are discussed. 相似文献
11.
This paper investigates the cryogenic fatigue delamination behavior of glass fiber reinforced polymer woven laminates under Mode III loading. Fatigue delamination tests were conducted using split cantilever beam specimens at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). A finite element analysis was also employed to calculate the energy release rate. The temperature dependence of the fatigue delamination growth rate vs. energy release rate range is discussed. Fracture surfaces were examined by scanning electron microscopy to identify the delamination mechanisms under fatigue loading. The important conclusion we reach is that the Mode III fatigue delamination growth rates of woven laminates at cryogenic temperatures are lower than that at room temperature. 相似文献
12.
In this paper, the mixed-mode interlaminar fracture behaviour of woven carbon-epoxy composite was investigated based on experimental
and numerical analyses. A modified version of Arcan specimen was employed to conduct a mixed mode fracture test using a special
loading device. A full range of mixed-mode loading conditions including pure mode-I and pure mode-II loading were created
and tested. This test method has a simple procedure, clamping/unclamping the specimens are easy to achieve and only one type
of specimen is required to generate all loading conditions. Also, finite element analysis was carried out for different loading
conditions in order to determine correction factors needed for fracture toughness calculations. Interlaminar fracture toughness
was determined experimentally with the modified version of the Arcan specimen under different mixed-mode loading conditions.
Results indicated that the interlaminar cracked specimen is tougher in shear loading condition and weaker in tensile loading
condition. Response of woven carbon-epoxy composite was also investigated through several criteria and the best criterion
was selected. The interlaminar fracture surfaces of the carbon-epoxy composite under different mixed-mode loading conditions
are examined by scanning electron microscopy (SEM). 相似文献
13.
14.
Yasuhide Shindo Akihiro Inamoto Fumio Narita Katsumi Horiguchi 《Engineering Fracture Mechanics》2006,73(14):2080-2090
The cryogenic fatigue delamination behavior of glass fiber reinforced polymer woven laminates under Mode I loading has been investigated experimentally and numerically. Fatigue delamination tests were conducted using double cantilever beam specimens at room temperature, liquid nitrogen temperature (77 K) and liquid helium temperature (4 K). Fracture surface examination using scanning electron microscopy revealed delamination mechanisms under fatigue loading. A finite element analysis was also employed to calculate the J-integral range and damage distributions. The effects of temperature and loading condition on the fatigue delamination growth rates were discussed. 相似文献
15.
This paper describes an experimental study on the fatigue damage behavior of GFRP woven laminates in terms of stiffness degradation and residual strength under cyclic loading at low temperatures. Uniaxial, load-controlled, tension-tension fatigue tests were conducted at room and low temperatures. The applied stress versus cycles to failure (S-N) relationships and fatigue limits were obtained for the GFRP woven laminates and the microcrack evolution due to fatigue loading was characterized using optical microscopy. Temperatures were also measured using a thermocouple embedded in the center of the specimens. 相似文献
16.
We study the effect of magnetic field on the fracture behavior of the metastable austenitic stainless steels at cryogenic
temperatures. Elastic-plastic fracture toughness tests were performed on compact tension specimens in liquid helium at 4 K
with and without a magnetic field, and the effect of magnetic field on the cryogenic fracture toughness was discussed. Quantitative
phase analysis was also done by magnetic method, and the fracture surfaces were examined by scanning electron microscopy to
correlate with the fracture properties. 相似文献
17.
18.
The purpose of this work was to determine the toughening mechanisms in interlayered quasi-isotropic glass–fibre reinforced polyester resin (GFRP) composites. Particles of polyethylene and aluminium tri-hydrate, Al(OH)3, were mixed with the polyester resin prior to laminating with woven E-glass-fibre cloth. Mode-I, mode-II, and impact tests were performed to determine critical strain energy-release rates (GIc and GIIc), absorbed energy and residual compressive strength for the laminates with and without particulate additions. Mode-I and mode-II delamination toughness were characterized using double cantilever beam (DCB) and end-notched flexure (ENF) specimens, respectively, and the delaminated surfaces of specimens were examined using scanning electron microscopy (SEM) to investigate the interlaminar morphology after fracture. The results indicate that the interlaminar toughness (GIc and GIIc), absorbed energy and residual compressive strength values of the GFRP composite increases with increase of particle content. The improved behaviour of particle containing GFRP is linked to stress-concentration induced plastic deformation and crack bridging. Polyethylene particles increase the toughness of the matrix material, which results in composites with higher values of mode-I, mode-II and impact than the composites with aluminium tri-hydrate particles. © 1998 Chapman & Hall 相似文献
19.
This paper investigates theoretically and experimentally the cryogenic fracture behavior of cracked piezoelectric ceramics under electric fields. Fracture tests were performed in three-point bending with the single-edge precracked-beam specimens at room temperature and liquid nitrogen temperature (77 K), and the fracture loads under electric fields were obtained. Plane strain finite element analysis was also carried out using temperature-dependent material properties of the piezoelectric ceramics, and the dependence of the energy release rate on the electric field and temperature was discussed. In addition, possible mechanisms for cryogenic fracture were examined by scanning electron microscopy. 相似文献
20.
《Science and Technology of Advanced Materials》2003,4(4):319-326
This paper discusses the fracture and the adiabatic heating of austenitic stainless steels that may be used in cryogenic structures for the superconducting magnets of magnetic fusion reactors. Elastic–plastic fracture toughness tests were performed on compact specimens in liquid helium at 4 K. Adiabatic heating was detected by measuring the internal temperature. The effect of test specimen size and side grooving on the cryogenic fracture toughness, and the temperature rise during dynamic crack growth are examined. A size independent toughness parameter results in the case of side-grooved specimens. The effect of inclusion content on the fracture mechanics parameters is also discussed. 相似文献