scholarly journals Open hole size effects on tensile properties of 3D braided composites

2021 ◽  
Vol 72 (05) ◽  
pp. 545-551
Author(s):  
SHUANGQIANG LIANG ◽  
QIHONG ZHOU ◽  
GE CHEN
Keyword(s):  
Size Effects ◽  
Uniaxial Tensile ◽  
Braided Composites ◽  
Notched Specimen ◽  
Stress Criterion ◽  
Notched Specimens ◽  
3D Braided Composites ◽  
Open Hole ◽  
Uniaxial Tensile Stress ◽  
Notched Strength

Owing to the excellent integrated structure, notch-insensitivity, delamination-free characteristics, 3D braided composites have a broad range of engineering applications. In this paper, the notch size effects on two types of 3D braided composites were experimentally examined. Style I incorporated 40% of longitudinal lay-in yarns. Style II was the pure braids. The Point Stress Criterion (PSC) was applied to predict the open-hole strength of 3D braided composites. It is found the 3D braided composites can keep higher proportion residual strength after involving the different circular hole sizes compared to plain woven laminates. The open-hole pure braided specimen shows better performance than that the braids with longitudinal yarns, the lay-in longitudinal yarns improve neither specimens’ un-notched strength, nor the modulus. The predicted open-hole strength were compared with experimental results. The traditional analytical method can predict the open-hole strength of 3D braided composite to some extent. Under uniaxial tensile stress, the failure behaviour of two types of 3D braided specimens are different. For un-notched specimen, clear cracks usually show up on the Style II specimen, while it is not true for Style I coupon. For notched specimen, the crack of both notched specimens will propagate along the notch and finally render the specimen to fail

Impact tensile behavior and frequency response of 3D braided composites

2011 ◽  
Vol 82 (3) ◽  
pp. 280-287 ◽  
Author(s):  
Xuehui Gan ◽  
Jianhua Yan ◽  
Bohong Gu ◽  
Baozhong Sun
Keyword(s):  
High Strain Rate ◽  
Strain Rate ◽  
Tensile Properties ◽  
High Strain ◽  
Tensile Modulus ◽  
Tensile Failure ◽  
Uniaxial Tensile ◽  
Strain Rates ◽  
Braided Composites ◽  
3D Braided Composites

The uniaxial tensile properties of 4-step 3D braided E-glass/epoxy composites under quasi-static and high-strain rate loadings have been investigated to evaluate the tensile failure mode at different strain rates. The uniaxial tensile properties at high strain rates from 800/s to 2100/s were tested using the split Hopkinson tension bar (SHTB) technique. The tensile properties at quasi-static strain rate were also tested and compared with those in high strain rates. Z-transform theory is applied to 3D braided composites to characterize the system dynamic behaviors in frequency domain. The frequency responses and the stability of 3D braided composites under quasi-static and high-strain rate compression have been analyzed and discussed in the Z-transform domain. The results indicate that the stress-strain curves are rate sensitive, and tensile modulus, maximum tensile stress and corresponding tensile strain are also sensitive to the strain rate. The tensile modulus, maximum tensile stress of the 3D braided composites are linearly increased with the strain rate. With increasing of the strain rate (from 0.001/s to 2100/s), the tensile failure of the 3D braided composite specimens has a tendency of transition from ductile failure to brittle failure. The magnitude response and phase response is very different in quasi-static loading with that in high-strain rate loading. The 3D braided composite system is more stable at high strain rate than quasi-static loading.

Open hole tension and compression behavior of 3D braided composites

2020 ◽  
Vol 41 (6) ◽  
pp. 2455-2465
Author(s):  
Liang Shuangqiang ◽  
Zhou Qihong ◽  
Chen Ge ◽  
Frank Ko
Keyword(s):  
Braided Composites ◽  
Compression Behavior ◽  
3D Braided Composites ◽  
Open Hole ◽  
Tension And Compression

Mechanical Property of Glass Mat Composite With Open Hole

2012 ◽  
Author(s):  
Zhiyuan Zhang ◽  
Yuqiu Yang ◽  
Hiroyuki Hamada
Keyword(s):  
Mechanical Property ◽  
Unsaturated Polyester ◽  
Element Analysis ◽  
Good Correspondence ◽  
Characteristic Distance ◽  
Linear Elastic ◽  
Notched Specimens ◽  
Open Hole ◽  
Notched Strength ◽  
Glass Mat

In using process, joints and fasteners always became the weakest area around holes and easy to generate initial damage. At current study, glass chopped fiber mat and unsaturated polyester were used to fabricate glass mat composite (GMC) plates. The influence of open-hole on mechanical property was investigated from tensile test. The decreasing ratio of notched strength from unnotched strength was compared with different size of holes to evaluate the influence of holes size on the sensitivity of GMC. Two sizes of drills, were employed to make drilling hole on the materials. Different damage areas in notched specimens were distinguished. Finally, in order to describe the property of GMC in resistance on open holes, the concept of characteristic distance was introduced. The values were calculated by finite element analysis software (MSC-Marc.) in linear elastic method. Furthermore, the characteristic distance was found that it had a good correspondence with damage characteristics.

scholarly journals Progressive Failure Analysis in Open-Hole Tensile Composite Laminates of Airplane Stringers Based on Tests and Simulations

2020 ◽  
Vol 11 (1) ◽  
pp. 185
Author(s):  
Jian Shi ◽  
Mingbo Tong ◽  
Chuwei Zhou ◽  
Congjie Ye ◽  
Xindong Wang
Keyword(s):  
Failure Analysis ◽  
Composite Laminates ◽  
Progressive Failure ◽  
Tensile Load ◽  
Fiber Failure ◽  
Stress Criterion ◽  
Progressive Failure Analysis ◽  
Analysis Technique ◽  
Open Hole ◽  
Failure Types

The failure types and ultimate loads for eight carbon-epoxy laminate specimens with a central circular hole subjected to tensile load were tested experimentally and simulated using two different progressive failure analysis (PFA) methodologies. The first model used a lamina level modeling based on the Hashin criterion and the Camanho stiffness degradation theory to predict the damage of the fiber and matrix. The second model implemented a micromechanical analysis technique coined the generalized method of cells (GMC), where the 3D Tsai–Hill failure criterion was used to govern matrix failure, and the fiber failure was dictated by the maximum stress criterion. The progressive failure methodology was implemented using the UMAT subroutine within the ABAQUS/implicit solver. Results of load versus displacement and failure types from the two different models were compared against experimental data for the open hole laminates subjected to tensile displacement load. The results obtained from the numerical simulation and experiments showed good agreement. Failure paths and accurate damage contours for the tested specimens were also predicted.

Sign in / Sign up

Export Citation Format

Share Document