Scaling Effects on the Tensile Strength of Fibrous Composites

2012 ◽  
Vol 525-526 ◽  
pp. 149-152
Author(s):  
Fang Wang ◽  
Lu Li ◽  
Zhi Qian Chen
Keyword(s):  
Tensile Strength ◽  
Weak Link ◽  
Fiber Strength ◽  
Primary Objective ◽  
Tensile Behaviour ◽  
Scaling Effects ◽  
Proposed Model ◽  
Random Nature ◽  
Two Parameter ◽  
Strength Distributions

The primary objective of this paper is to illustrate the effects of weak-link scaling on the tensile behaviour of fiber-reinforced composites. The proposed model takes into account the random nature of fiber strength, which is given by a two-parameter Weibull distribution function. Several hundred Monte-Carlo replications are executed to simulate the statistical strength distributions of the composites. It is shown that probabilistic tensile strength distributions and size scaling is dependent on both the stress redistribution and the fiber strength statistics.

scholarly journals Scaling Analysis of the Tensile Strength of Bamboo Fibers Using Weibull Statistics

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Jiaxing Shao ◽  
Fang Wang ◽  
Lu Li ◽  
Junqian Zhang
Keyword(s):  
Tensile Strength ◽  
Weak Link ◽  
Fiber Strength ◽  
Scaling Analysis ◽  
Weibull Statistics ◽  
Tension Tests ◽  
Proposed Model ◽  
Bamboo Fibers ◽  
Random Nature ◽  
Two Parameter

This study demonstrates the effect of weak-link scaling on the tensile strength of bamboo fibers. The proposed model considers the random nature of fiber strength, which is reflected by using a two-parameter Weibull distribution function. Tension tests were performed on samples that could be scaled in length. The size effects in fiber length on the strength were analyzed based on Weibull statistics. The results verify the use of Weibull parameters from specimen testing for predicting the strength distributions of fibers of longer gauge lengths.

Tensile Behaviour of Functionally Graded Braided Carbon Fibre/Epoxy Composite Material

2002 ◽  
Vol 10 (4) ◽  
pp. 307-314 ◽  
Author(s):  
Zheng-Ming Huang ◽  
Qiongan Wang ◽  
S. Ramakrishna
Keyword(s):  
Tensile Strength ◽  
Carbon Fibre ◽  
Research Work ◽  
Tensile Modulus ◽  
Primary Objective ◽  
Functionally Graded ◽  
Tensile Behaviour ◽  
Braided Composites ◽  
Graded Materials ◽  
Braiding Angle

The primary objective of this research work was to investigate experimentally the tensile behaviour of Functionally Graded Materials (FGM) made from tubular braided composites and to find out the relationship between the tensile property of the FGM and that of the corresponding non-FGM. Composites were made using tubular braided carbon fibre fabrics and an epoxy resin. The FGM specimens had varying braiding angles and the non-FGM specimens had constant braiding angles. The effect of braiding angle on the composite properties was established from the test results for the non-FGM specimens. It was shown that both the tensile strength and modulus decreased as the braiding angle increased. The tensile behaviour of the FGM specimens was demonstrated to be related to that of the non-FGM specimens. The tensile modulus of an FGM specimen could be estimated from the tensile moduli of a series of non-FGM specimens. The tensile strength of an FGM specimen was a function of its largest braiding angle, and was higher than that of a non-FGM specimen with a braiding angle equal to this largest braiding angle.

A Two-Parameter Model of FRP Laminates Stiffness Reduction

2011 ◽  
Vol 236-238 ◽  
pp. 1187-1194 ◽  
Author(s):  
Tai Feng Zhang ◽  
Xiao Hua Yang ◽  
Wen Sheng Sun ◽  
Zeng Jie Cai
Keyword(s):  
Fiber Strength ◽  
Mechanical Analysis ◽  
Matrix Crack ◽  
Fibre Breakage ◽  
Damage Models ◽  
Stiffness Reduction ◽  
Reinforced Polymer ◽  
Proposed Model ◽  
Fibre Reinforced Polymer ◽  
Two Parameter

Matrix crack and fibre breakage are the main damage models of the fibre reinforced polymer (FRP) laminates under cyclic loading. In this paper, meso-mechanical analysis is used and a two-parameter model is developed to describe the stiffness reduction. Based on the probability distribution function of fiber strength, the evolution of fibre breakage is deduced. Then with the help of the damage evolution, the stiffness reduction of laminates can be predicted. As an example, the stiffness reduction of grass fibre reinforced polymer (GFRP) laminate is made and the simulation results show that the proposed model has good capacity to describe the stiffness reduction of FRP laminates resulted in the combination of matrix crack and fibre breakage.

scholarly journals Design of Cascaded CNN for Medical Image Super Resolution

2021 ◽  
Vol 7 (3) ◽  
pp. 22-29
Author(s):  
Kajol Singh ◽  
Manish Saxena
Keyword(s):  
Neural Networks ◽  
Medical Image ◽  
Research Work ◽  
Super Resolution ◽  
Primary Objective ◽  
Lighting Conditions ◽  
Proposed Model ◽  
Filter Size ◽  
Medical Image Reconstruction ◽  
Image Super Resolution

The images captured through a camera usually belong to over or under exposed conditions. The reason may be inappropriate lighting conditions or camera resolution. Hence, it is of utmost importance to have a few enhancement techniques that could make these artefacts look better. Hence, the primary objective pertaining to the adjustment and enhancement techniques is to enhance the characteristics of an image. The initial numeric values related to an image get distorted when an image is enhanced. Therefore, enhancement techniques should be designed in such a way that the image quality isn’t compromised. This research work is focused on proposed a network design for deep convolution neural networks for application of super resolution techniques. To improve the complexity of existing techniques this work is intended towards network designs, different filter size and CNN architecture. The CNN model is most effective model for detection and segmentation in image. This model will improve the efficiency of medical image reconstruction from LR to HR. The proposed model showed its efficiency not only PET medical images but also on retinal database and achieved advance results as compared to existing works.

The Tensile Behavior of High-Strength Carbon Fibers

2016 ◽  
Vol 22 (4) ◽  
pp. 841-844 ◽  
Author(s):  
Tye Langston
Keyword(s):  
Young’S Modulus ◽  
Carbon Fibers ◽  
Young's Modulus ◽  
Weak Link ◽  
Fiber Strength ◽  
Fiber Surface ◽  
High Strength ◽  
Carbon Filament ◽  
Specific Strength ◽  
Macro Scale

AbstractCarbon fibers exhibit exceptional properties such as high stiffness and specific strength, making them excellent reinforcements for composite materials. However, it is difficult to directly measure their tensile properties and estimates are often obtained by tensioning fiber bundles or composites. While these macro scale tests are informative for composite design, their results differ from that of direct testing of individual fibers. Furthermore, carbon filament strength also depends on other variables, including the test length, actual fiber diameter, and material flaw distribution. Single fiber tensile testing was performed on high-strength carbon fibers to determine the load and strain at failure. Scanning electron microscopy was also conducted to evaluate the fiber surface morphology and precisely measure each fiber’s diameter. Fiber strength was found to depend on the test gage length and in an effort to better understand the overall expected performance of these fibers at various lengths, statistical weak link scaling was performed. In addition, the true Young’s modulus was also determined by taking the system compliance into account. It was found that all properties (tensile strength, strain to failure, and Young’s modulus) matched very well with the manufacturers’ reported values at 20 mm gage lengths, but deviated significantly at other lengths.

Effect of infill and density pattern on the mechanical behaviour of ABS parts manufactured by FDM using Taguchi and ANOVA approach

2021 ◽  
Vol 111 (2) ◽  
pp. 66-77
Author(s):  
M. Othmani ◽  
K. Zarbane ◽  
A. Chouaf
Keyword(s):  
Tensile Strength ◽  
Computer Aided Design ◽  
Numerical Test ◽  
Acrylonitrile Butadiene Styrene ◽  
Tensile Behaviour ◽  
Element Analysis ◽  
Mechanical Tensile ◽  
Experimental Values ◽  
The Cost ◽  
Aided Design

Purpose: The present work aims to investigate the effect of many infill patterns (rectilinear, line, grid, triangles, cubic, concentric, honeycomb, 3D honeycomb) and the infill density on the mechanical tensile strength of an Acrylonitrile Butadiene Styrene (ABS) test specimen manufactured numerically by FDM. Design/methodology/approach: Computer-Aided Design (CAD) software has been used to model the geometry and the mesostructure of the test specimens in a fully automatic manner from a G-code file by using a script. Then, a Numerical Design of Experiments (NDoE) has been carried out by using Taguchi method and the Analysis of Variance (ANOVA). The tensile behaviour of these numerical test specimens has been studied by the Finite Element Analysis (FEA). Findings: The FEA results showed that a maximal Ultimate Tensile Strength (UTS) was reached by using the ‘concentric’ infill pattern combined with an infill density of 30%. The results also show that the infill pattern and the infill density are significant factors. Research limitations/implications: The low infill densities of 20% and 30% that have already been used in many previous studies, we have also applied it in order to reduce the time of the simulations. Indeed, with high infill density, the simulations take a very excessive time. In an ongoing study, we predicted higher percentages. Practical implications: This study provided an important modelling tool for the design and manufacture of functional parts and helps the FDM practitioners and engineers to manufacture strong and lightweight FDM parts by choosing the optimal process parameters. Originality/value: This study elucidated the effect of various infill patterns on the tensile properties of the test specimens and applied for the first time a NDoE using numerical test specimens created by the mesostructured approach, which considerably minimized the cost of the experiments while obtaining an error of 6.8% between the numerical and the experimental values of the UTS.

Banking Credit Scoring Assessment Using Predictive K-Nearest Neighbour (PKNN) Classifier

2017 ◽  
pp. 332-350
Author(s):  
Saroj Kanta Jena ◽  
Anil Kumar ◽  
Maheshwar Dwivedy
Keyword(s):  
Service Provider ◽  
Classification Accuracy ◽  
Credit Scoring ◽  
Primary Objective ◽  
Scientific Methodology ◽  
Nearest Neighbour ◽  
K Value ◽  
Proposed Model ◽  
Credit Worthiness ◽  
Banking Credit

Credit scoring models is a scientific methodology adopted by credit providers to assess the credit worthiness of applicants. The primary objective of such models has been to predict the potentiality of the loan applicant. A proper evaluation of the credit can help the service provider to determine whether to grant or to reject credit. Therefore, the objective of the study is to predict banking credit scoring assessment using Predictive K-Nearest Neighbour (PKNN) classifier. For the purpose of analysis two different credit approval datasets: Australian credit and German credit have been used. The results from the study show that the proposed model used for classification works better on credit dataset. Here, the study firstly attempted to find the optimal ‘K' value of the neighbourhood so that the classifier is tuned to forecast the credit worthiness and secondly, validated our proposed model on two credit approval datasets by checking the performance of the proposed models on the basis of classification accuracy.

scholarly journals A New Extended Two-Parameter Distribution: Properties, Estimation Methods, and Applications in Medicine and Geology

Mathematics ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1578 ◽  
Author(s):  
Hazem Al-Mofleh ◽  
Ahmed Z. Afify ◽  
Noor Akma Ibrahim
Keyword(s):  
Estimation Method ◽  
Estimation Methods ◽  
Parameter Distribution ◽  
Model Parameters ◽  
Unknown Parameters ◽  
Proposed Model ◽  
Rate Functions ◽  
The Mean ◽  
Modeling Data ◽  
Two Parameter

In this paper, a new two-parameter generalized Ramos–Louzada distribution is proposed. The proposed model provides more flexibility in modeling data with increasing, decreasing, J-shaped, and reversed-J shaped hazard rate functions. Several statistical properties of the model were derived. The unknown parameters of the new distribution were explored using eight frequentist estimation approaches. These approaches are important for developing guidelines to choose the best method of estimation for the model parameters, which would be of great interest to practitioners and applied statisticians. Detailed numerical simulations are presented to examine the bias and the mean square error of the proposed estimators. The best estimation method and ordering performance of the estimators were determined using the partial and overall ranks of all estimation methods for various parameter combinations. The performance of the proposed distribution is illustrated using two real datasets from the fields of medicine and geology, and both datasets show that the new model is more appropriate as compared to the Marshall–Olkin exponential, exponentiated exponential, beta exponential, gamma, Poisson–Lomax, Lindley geometric, generalized Lindley, and Lindley distributions, among others.

scholarly journals A Novel Discrete Grey Model and Its Application

2019 ◽  
Vol 2019 ◽  
pp. 1-6 ◽  
Author(s):  
Wen-Ze Wu ◽  
Jianming Jiang ◽  
Qi Li
Keyword(s):  
Tensile Strength ◽  
Arbitrary Number ◽  
Prediction Accuracy ◽  
Historical Data ◽  
Prediction Performance ◽  
Grey Model ◽  
Original Series ◽  
Proposed Model ◽  
Grey Models ◽  
Future Data

This paper aims to further increase the prediction accuracy of the grey model based on the existing discrete grey model, DGM(1,1). Herein, we begin by studying the connection between forecasts and the first entry of the original series. The results comprehensively show that the forecasts are independent of the first entry in the original series. On this basis, an effective method of inserting an arbitrary number in front of the first item of the original series to extract messages is applied to produce a novel grey model, which is abbreviated as FDGM(1,1) for simplicity. Incidentally, the proposed model can even forecast future data using only three historical data. To demonstrate the effectiveness of the proposed model, two classical examples of the tensile strength and life of the product are employed in this paper. The numerical results indicate that FDGM(1,1) has a better prediction performance than most commonly used grey models.

Case study on aircraft tyre wear in Y12 aircraft tyres

2018 ◽  
Vol 122 (1253) ◽  
pp. 1123-1144
Author(s):  
K. A. Dulani Daminda Kuruppu ◽  
C. J. Hettiarachchi
Keyword(s):  
Tensile Strength ◽  
Reduction Rate ◽  
Primary Objective ◽  
Volume Loss ◽  
Left Main ◽  
Elongation At Break ◽  
Hardness Tests ◽  
Surface Morphologies ◽  
Tyre Wear

ABSTRACTThe primary objective of this research was to analyse the discrepancies in polymeric properties in Y12 aircraft tyres after 50 landings. Tensile strength and elongation test, abrasion test and hardness tests were carried out for the nose and main gear tyres after the completion of 50 landings. Surface morphologies of the tyre samples were observed using SEM. ISO specifications were followed for each experimental method during testing. There was a reduction in both median tensile strength and elongation at break in aircraft tyres after 50 landings but the reduction rate of both parameters were lower in Tyre 2 (nose wheel tyre) compared with Tyre 1 (left main wheel tyre) and Tyre 3 (right main wheel tyre). The highest percentage of mean volume loss was reported for Tyre 3 (3.88%). In addition, the least percentage of mean volume loss was obtained in Tyre 2 (2.98%). The percentage of hardness reduction was highest in Tyre 2 (6.9%). The surface roughness was induced to the tyre surface after completion of 50 landings.

Sign in / Sign up

Export Citation Format

Share Document