Characterisation of Moisture Absorption Effects on the Strength of Composite Materials

2015 ◽  
Vol 1125 ◽  
pp. 69-73 ◽  
Author(s):  
King Jye Wong ◽  
Haris Ahmad Israr ◽  
Mohd Nasir Tamin
Keyword(s):  
Composite Materials ◽  
Polymer Composites ◽  
Exponential Decay ◽  
Moisture Absorption ◽  
Scattered Data ◽  
Dominant Factor ◽  
Residual Property ◽  
Proposed Model ◽  
Property Model ◽  
Temperature Factors

In the present work, the variation of the tensile strengths of various polymers and polymer composites due to moisture ageing is investigated. The stacking sequences of the composites include 0o, 90o, ±45o and quasi-isotropic laminates. The variation in the strength of material is then fitted using a residual property model. Results show that the proposed model characterises well the variation in the strengths that exhibits a typical trend, where there is no obvious scattered data. In fibre dominated laminates (0o), the degradation parameter seems to be influenced by the type of material, whereas for matrix dominated laminates (90o), ageing temperature appears to be the dominant factor that affects the degradation trend. As for [±45]2S and adhesives, exponential decay trend is observed. This model could be further improved to include the material and temperature factors.

Microstructure and Physical Properties of Clay-Polymer Composites

2000 ◽  
Vol 628 ◽  
Author(s):  
T.N. Blanton ◽  
D. Majumdar ◽  
S.M. Melpolder
Keyword(s):  
Composite Materials ◽  
Physical Properties ◽  
Polymer Composites ◽  
Basal Plane ◽  
X Ray Diffraction ◽  
X Ray ◽  
Layered Clay

ABSTRACTClay-polymer nanoparticulate composite materials are evaluated by the X-ray diffraction technique. The basal plane spacing provided information about the degree of intercalation and exfoliation of the 2: 1 layered clay structure. Both intercalation and exfoliation are controlled by the identity of the polymer and the clay:polymer ratio.

Hybrid polymer composite materials. Part 2. Preparation technology

2020 ◽  
pp. 8-13
Keyword(s):  
Composite Materials ◽  
Impact Toughness ◽  
Polymer Composites ◽  
The Other ◽  
Polymer Materials ◽  
Hybrid Polymer ◽  
Preparation Technology ◽  
Advantages And Disadvantages ◽  
Hybrid Polymer Composite ◽  
The One

The main methods (pressing and winding) of the processing of hybrid polymer composites to obtain items were examined. Advantages and disadvantages of the methods were noted. Good combinations of different-module fibers (carbon, glass, boron, organic) in hybrid polymer materials are described, which allow one to prepare materials with high compression strength on the one hand, and to increase fracture energy of samples and impact toughness on the other hand.

scholarly journals A General Temperature-Dependent Stress–Strain Constitutive Model for Polymer-Bonded Composite Materials

Polymers ◽  
2021 ◽  
Vol 13 (9) ◽  
pp. 1393
Author(s):  
Xiaochang Duan ◽  
Hongwei Yuan ◽  
Wei Tang ◽  
Jingjing He ◽  
Xuefei Guan
Keyword(s):  
Composite Materials ◽  
Constitutive Model ◽  
Model Parameters ◽  
Temperature Dependent ◽  
Stress Strain ◽  
Proposed Model ◽  
Single Temperature ◽  
Testing Data ◽  
Bonded Composite ◽  
Tension And Compression

This study develops a general temperature-dependent stress–strain constitutive model for polymer-bonded composite materials, allowing for the prediction of deformation behaviors under tension and compression in the testing temperature range. Laboratory testing of the material specimens in uniaxial tension and compression at multiple temperatures ranging from −40 ∘C to 75 ∘C is performed. The testing data reveal that the stress–strain response can be divided into two general regimes, namely, a short elastic part followed by the plastic part; therefore, the Ramberg–Osgood relationship is proposed to build the stress–strain constitutive model at a single temperature. By correlating the model parameters with the corresponding temperature using a response surface, a general temperature-dependent stress–strain constitutive model is established. The effectiveness and accuracy of the proposed model are validated using several independent sets of testing data and third-party data. The performance of the proposed model is compared with an existing reference model. The validation and comparison results show that the proposed model has a lower number of parameters and yields smaller relative errors. The proposed constitutive model is further implemented as a user material routine in a finite element package. A simple structural example using the developed user material is presented and its accuracy is verified.

scholarly journals A Phenomenological Primary–Secondary–Tertiary Creep Model for Polymer-Bonded Composite Materials

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2353
Author(s):  
Xiaochang Duan ◽  
Hongwei Yuan ◽  
Wei Tang ◽  
Jingjing He ◽  
Xuefei Guan
Keyword(s):  
Composite Materials ◽  
Creep Behavior ◽  
Reference Model ◽  
Creep Model ◽  
Creep Process ◽  
Validation Dataset ◽  
Testing Conditions ◽  
Proposed Model ◽  
Testing Data ◽  
Bonded Composite

This study develops a unified phenomenological creep model for polymer-bonded composite materials, allowing for predicting the creep behavior in the three creep stages, namely the primary, the secondary, and the tertiary stages under sustained compressive stresses. Creep testing is performed using material specimens under several conditions with a temperature range of 20 °C–50 °C and a compressive stress range of 15 MPa–25 MPa. The testing data reveal that the strain rate–time response exhibits the transient, steady, and unstable stages under each of the testing conditions. A rational function-based creep rate equation is proposed to describe the full creep behavior under each of the testing conditions. By further correlating the resulting model parameters with temperature and stress and developing a Larson–Miller parameter-based rupture time prediction model, a unified phenomenological model is established. An independent validation dataset and third-party testing data are used to verify the effectiveness and accuracy of the proposed model. The performance of the proposed model is compared with that of an existing reference model. The verification and comparison results show that the model can describe all the three stages of the creep process, and the proposed model outperforms the reference model by yielding 28.5% smaller root mean squared errors on average.

scholarly journals Numerical Simulation of Water Absorption and Swelling in Dehulled Barley Grains during Canned Porridge Cooking

Processes ◽  
2018 ◽  
Vol 6 (11) ◽  
pp. 230 ◽  
Author(s):  
Lei Wang ◽  
Mengting Wang ◽  
Mingming Guo ◽  
Xingqian Ye ◽  
Tian Ding ◽  
...  
Keyword(s):  
Moisture Absorption ◽  
Three Dimensional ◽  
Processing Conditions ◽  
Relative Deviation ◽  
Cooking Process ◽  
Proposed Model ◽  
Hygroscopic Swelling ◽  
3D Numerical Model ◽  
Barley Grains ◽  
Experimental Values

Understanding the hydration behavior of cereals during cooking is industrially important in order to optimize processing conditions. In this study, barley porridge was cooked in a sealed tin can at 100, 115, and 121 °C, respectively, and changes in water uptake and hygroscopic swelling in dehulled barley grains were measured during the cooking of canned porridge. In order to describe and better understand the hydration behaviors of barley grains during the cooking process, a three-dimensional (3D) numerical model was developed and validated. The proposed model was found to be adequate for representing the moisture absorption characteristics with a mean relative deviation modulus (P) ranging from 4.325% to 5.058%. The analysis of the 3D simulation of hygroscopic swelling was satisfactory for describing the expansion in the geometry of barley. Given that the model represented the experimental values adequately, it can be applied to the simulation and design of cooking processes of cereals grains, allowing for saving in both time and costs.

The influence of functionalization time of carbon nanotube on the mechanical properties of the epoxy composites

2017 ◽  
Vol 51 (12) ◽  
pp. 1693-1701 ◽  
Author(s):  
EA Zakharychev ◽  
EN Razov ◽  
Yu D Semchikov ◽  
NS Zakharycheva ◽  
MA Kabina
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Carbon Nanotube ◽  
Composite Materials ◽  
Polymer Composites ◽  
Epoxy Composites ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

This paper investigates the structure, length, and percentage of functional groups of multi-walled carbon nanotubes (CNT) depending on the time taken for functionalization in HNO3 and H2SO4 mixture. The carbon nanotube content and influence of functionalization time on mechanical properties of polymer composite materials based on epoxy matrix are studied. The extreme dependencies of mechanical properties of carbon nanotube functionalization time of polymer composites were established. The rise in tensile strength of obtained composites reaches 102% and elastic modulus reaches 227% as compared to that of unfilled polymer. The composites exhibited best mechanical properties by including carbon nanotube with 0.5 h functionalization time.

scholarly journals An Exponential Decay Model for the Deterministic Correlations in Axial Compressors

2019 ◽  
Vol 141 (2) ◽  
Author(s):  
Yangwei Liu ◽  
Yumeng Tang ◽  
Baojie Liu ◽  
Lipeng Lu
Keyword(s):  
Exponential Decay ◽  
Equation System ◽  
Time Averaging ◽  
Mean Flow ◽  
Flow Solver ◽  
Axial Compressors ◽  
Routine Design ◽  
Proposed Model ◽  
Exponential Decay Model ◽  
Two Stages

The unsteady blade row interaction (UBRI) is inherent and usually has a large effect on performance in multistage axial compressors. The effect could be considered by using the average-passage equation system (APES) in steady-state environment by introducing the deterministic correlations (DC). How to model the DC is the key in APES method. The primary purpose of this study is to develop a DC model for compressor routine design. The APES technique is investigated by using a 3D viscous unsteady and time-averaging Computational fluid dynamics (CFD) flow solver developed in our previous studies. Based on DC characteristics and its effects on time-averaged flow, an exponential decay DC model is proposed and implemented into the developed time-averaging solver. Steady, unsteady, and time-averaging simulations are conducted on the investigation of the UBRI and the DC model in the first transonic stage of NASA 67 and the first two stages of a multistage compressor. The DC distributions and mean flow fields from the DC model are compared with the unsteady simulations. The comparison indicates that the proposed model can take into account the major part of UBRI and provide significant improvements for predicting compressor characteristics and spanwise distributions of flow properties in axial compressors, compared with the steady mixing plane method.

A review investigating the influence of nanofiller addition on the mechanical, thermal and water absorption properties of cellulosic fibre reinforced polymer composite

2021 ◽  
pp. 152808372110575
Author(s):  
Adnan Amjad ◽  
Aslina Anjang Ab Rahman ◽  
Habib Awais ◽  
Mohd Shukur Zainol Abidin ◽  
Junaid Khan
Keyword(s):  
Surface Treatment ◽  
Water Absorption ◽  
Polymer Composites ◽  
Moisture Absorption ◽  
Low Cost ◽  
Natural Fibre ◽  
Great Promise ◽  
Absorption Properties ◽  
Reinforced Polymer ◽  
Fibre Reinforced Polymer

Composite holds great promise for future materials considering its advantages such as excellent strength, stiffness, lightweight, and cost-effectiveness. Due to rising environmental concerns, the research speed gradually changes from synthetic polymer composites to natural fibre reinforced polymer composites (NFRPCs). Natural fibres are believed a valuable and robust replacement to synthetic silicates and carbon-based fibres, along with biodegradability, recyclability, low cost, and eco-friendliness. But the incompatibility between natural fibre and polymer matrices and higher moisture absorption percentage of natural fibre limitise their applications. To overcome these flaws, surface treatment of natural fibre and nanofiller addition have become some of the most important aspects to improve the performance of NFRPCs. This review article provides the most recent development on the effect of different nanofiller addition and surface treatment on the mechanical, thermal, and wetting behaviour of NFRPCs. It concludes that the fibre surface treatment and nanofillers in natural fibre polymer composites positively affect mechanical, thermal and water absorption properties. A systematic understanding in this field covers advanced research basics to stimulate investigation for fabricating NFRPCs with excellent performance.

Methodology for determining of adhesion strength of polymeric hardening-curing composite materials and adhesive join

2021 ◽  
pp. 181-183
Author(s):  
A.M. Mikhal’chenkov ◽  
I.V. Kozarez ◽  
S.A. Fes’kov ◽  
M.A. Mikhal’chenkova
Keyword(s):  
Composite Materials ◽  
Polymer Composites ◽  
Adhesion Strength ◽  
Adhesive Strength ◽  
Adhesive Joints ◽  
Breaking Force ◽  
Force Moment

The developed technique for determining the adhesive strength allows us to study both adhesive polymer composites and adhesive joints on the same device without the influence of the breaking force moment on the results obtained.

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