scholarly journals Influence of interface ply orientation on delamination growth in composite laminates

2021 ◽  
pp. 002199832110316
Author(s):  
A Raimondo ◽  
I Urcelay Oca ◽  
C Bisagni
Keyword(s):  
Fracture Toughness ◽  
Composite Laminates ◽  
Double Cantilever Beam ◽  
Numerical Approach ◽  
Field Variable ◽  
Numerical Analyses ◽  
Structural Components ◽  
Closure Technique ◽  
Ply Orientation ◽  
Delamination Propagation

The standard experimental procedures for determining the interlaminar fracture toughness are designed for delamination propagation in unidirectional specimens. However, in aerospace structural components, delamination usually occurs between plies at different orientations resulting in different damage mechanisms which can increase the value of the fracture toughness as the delamination propagates. Generally, numerical analyses employ the value measured at the delamination onset, leading to conservative results since the increase resistance of the delamination is neglected. In this paper, the fracture toughness and the R-curves of carbon/epoxy IM7/8552 are experimentally evaluated in coupons with delamination positioned at 0°/0° and 45°/−45° interfaces using Double Cantilever Beam (DCB) and Mixed-Mode Bending (MMB) tests. A simplified numerical approach based on the Virtual Crack Closure Technique (VCCT) is developed to simulate variable fracture toughness with the delamination length within a Finite Element code using a predefined field variable. The results of the numerical analyses compared with the experimental data in terms of load-displacement curves demonstrate the effectiveness of the proposed technique in simulating the increase resistance in delamination positioned between plies at 45°/−45° interface.

scholarly journals The Thickness Effect of PSF Nanofibrous Mat on Fracture Toughness of Carbon/Epoxy Laminates

Materials ◽  
2021 ◽  
Vol 14 (13) ◽  
pp. 3469
Author(s):  
Hamed Saghafi ◽  
Ali Nikbakht ◽  
Reza Mohammadi ◽  
Dimitrios Zarouchas
Keyword(s):  
Fracture Toughness ◽  
Composite Laminates ◽  
Double Cantilever Beam ◽  
Thickness Effect ◽  
Toughening Mechanism ◽  
Geometrical Features ◽  
Electrospinning Method ◽  
Fracture Tests ◽  
Mat Thickness ◽  
First Time

The geometrical features of nanofibers, such as nanomat thickness and the diameter of nanofibers, have a significant influence on the toughening behavior of composite laminates. In this study, carbon/epoxy laminates were interleaved with polysulfone (PSF) nanofibrous mats and the effect of the PSF nanomat thickness on the fracture toughness was considered for the first time. For this goal, the nanofibers were first produced by the electrospinning method. Then, double cantilever beam (DCB) specimens were manufactured, and mode-I fracture tests were conducted. The results showed that enhancing the mat thickness could increase the fracture toughness considerably (to about 87% with the maximum thickness). The toughening mechanism was also considered by presenting a schematic picture. Micrographs were taken using a scanning electron microscope (SEM).

Investigation on Interlaminar Mechanical Properties of Hybrid CFRP/VGCF Laminates

2009 ◽  
Vol 79-82 ◽  
pp. 1759-1762
Author(s):  
Yuan Li ◽  
Naoki Hori ◽  
Masahiro Arai ◽  
Hisao Fukunaga ◽  
Ning Hu
Keyword(s):  
Mechanical Properties ◽  
Finite Element Method ◽  
Fracture Toughness ◽  
Finite Element ◽  
Tensile Strength ◽  
Crack Growth ◽  
Double Cantilever Beam ◽  
Cohesive Elements ◽  
Cfrp Laminates ◽  
Delamination Propagation

In order to improve the interlaminar mechanical properties of CFRP laminate, hybrid CFRP/VGCF laminates have been fabricated by newly-developed powder method. The critical load at crack growth Pc and fracture toughness GIC have been found to be increased with VGCF interlayer through double cantilever beam (DCB) tests. Fracture surfaces of DCB specimens have also been observed to interpret this improvement mechanism. Moreover, numerical simulations using finite element method (FEM) with cohesive elements have been carried out to analyze the delamination propagation. The numerically obtained interlaminar tensile strength of hybrid CFRP/VGCF laminates has also been verified to be higher than that of base CFRP laminates.

RUUKKI RAEX 300

Alloy Digest ◽  
2012 ◽  
Vol 61 (2) ◽  
Keyword(s):  
Fracture Toughness ◽  
Wear Resistance ◽  
Shear Strength ◽  
Impact Toughness ◽  
Yield Strength ◽  
Physical Properties ◽  
Tensile Properties ◽  
High Strength ◽  
Structural Components ◽  
Wear Resistant

Abstract RUUKKI RAEX 300 (typical yield strength 900 MPa) is part of the Raex family of high-strength and wear-resistant steels with favorable hardness and impact toughness to extend life and decrease wear in structural components. This datasheet provides information on composition, physical properties, hardness, elasticity, tensile properties, and shear strength as well as fracture toughness. It also includes information on wear resistance as well as forming, machining, and joining. Filing Code: SA-643. Producer or source: Rautaruukki Corporation.

CYCLOPS BHT

Alloy Digest ◽  
1965 ◽  
Vol 14 (2) ◽  
Keyword(s):  
Fracture Toughness ◽  
Corrosion Resistance ◽  
Elevated Temperature ◽  
High Speed ◽  
High Speed Steel ◽  
High Strength ◽  
Heat Treating ◽  
High Load ◽  
Structural Components ◽  
Temperature Performance

Abstract Cyclops BHT is a low-alloy martensitic high-speed steel of the molybdenum type recommended for high strength, high load structural components designed for elevated temperature service. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties as well as fracture toughness. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, and joining. Filing Code: SA-173. Producer or source: Cyclops Corporation.

DOMEX 110XF

Alloy Digest ◽  
2003 ◽  
Vol 52 (5) ◽  
Keyword(s):  
Fracture Toughness ◽  
Physical Properties ◽  
Tensile Properties ◽  
High Strength Steel ◽  
Civil Engineering ◽  
High Strength ◽  
Heat Treating ◽  
Bend Strength ◽  
Structural Components ◽  
Very High

Abstract Domex 110XF is a very-high-strength steel that is used for automotive and civil engineering structural components. This datasheet provides information on composition, physical properties, hardness, tensile properties, and bend strength as well as fracture toughness. It also includes information on heat treating and joining. Filing Code: SA-512. Producer or source: SSAB Swedish Steel Inc.

Sign in / Sign up

Export Citation Format

Share Document