Refined constitutive, bridging, and contact laws for including effects of the impact-induced temperature rise in impact responses of composite plates with embedded SMA wires

Glass/Vinylester composite laminates are comprehensively characterised to assess its impact response behaviour under moisture exposure in marine structures. An instrumented drop weight impact machine is utilised to determine the impact responses of dry and immersed specimens in normal, salted and sea water. The specimens, which had three different thicknesses, were subjected to water exposure for a very long period of over 20 months before tested in a low-velocity impact experiment. Water uptake was measured primarily to study the degradation profiles of GRP laminates after being permeated by water. Matrix dissolution and interfacial damage observed on the laminates after prolonged moisture exposure while the absorption behaviour was found typically non-Fickian. The weight of the composite plates firstly increased because of water diffusion up to month 15 and then decreased due to matrix degradation. The specimens with 3, 6 and 9 mm thickness exhibited maximum water absorption corresponding to 2.6%, 0.7% and 0.5% weight gain, respectively. In general, the results indicated that water uptake and impact properties were affected by thickness and less by water type. Impact properties of prolonged immersed specimens reduced remarkably, and intense failure modes detected almost in all cases. The least sensitive to impact damage were wet specimens with 9 mm thickness as they indicated similar maximum load and absorbed energy for different impact energies.

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Temperature rise and parasitic infection interact to increase the impact of an invasive species

International Journal for Parasitology ◽

10.1016/j.ijpara.2016.12.004 ◽

2017 ◽

Vol 47 (5) ◽

pp. 291-296 ◽

Cited By ~ 22

Author(s):

Ciaran Laverty ◽

David Brenner ◽

Christopher McIlwaine ◽

Jack J. Lennon ◽

Jaimie T.A. Dick ◽

...

Keyword(s):

Invasive Species ◽

Temperature Rise ◽

Parasitic Infection ◽

The Impact

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Strength Loss in Composite Cylinders Under Impact

Journal of Engineering Materials and Technology ◽

10.1115/1.3226028 ◽

1988 ◽

Vol 110 (2) ◽

pp. 180-184 ◽

Cited By ~ 12

Author(s):

A. P. Christoforou ◽

S. R. Swanson

Keyword(s):

Composite Structures ◽

Composite Plates ◽

Strength Loss ◽

Pressure Vessels ◽

Fourier Series Expansion ◽

Lateral Impact ◽

Low Velocity ◽

Expansion Procedure ◽

The Impact ◽

Composite Cylinders

The problem of strength loss in composite structures due to impact appears to be important due to the sensitivity of advanced composites to these loadings. Although a number of studies have been carried out on impact of flat composite plates, relatively little work has been done on tubular geometries such as pressure vessels despite the usage in applications. We have addressed the problem of calculating strength loss due to low velocity, lateral impact of composite cylinders. In our model we use an existing Fourier Series expansion procedure to calculate ply stresses and strains, compare these values with allowables to predict fiber breakage during the impact, and finally use fracture mechanics to predict the strength loss due to the impact. Although the model is quite simplified, the general trends of experiments appear to be represented.

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Experimental Analysis of Different Coolants Used in Plasma Cutting Operation for the Improved Electrode Life

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.719-720.46 ◽

2015 ◽

Vol 719-720 ◽

pp. 46-49 ◽

Cited By ~ 1

Author(s):

Ginka Ranga Janardhana ◽

Mani Senthil Kumar ◽

B. Dhanasekar

Keyword(s):

Temperature Rise ◽

Metal Cutting ◽

Cooling System ◽

Heat Removal ◽

Plasma Cutting ◽

Life Test ◽

Flow Rates ◽

Optimal Flow ◽

Cutting Operation ◽

The Impact

The plasma cutting technology has been emerged as a developing technology which finds tremendous potential in fabrication and metal cutting industries. Thus for the cutting operation, the electrode inside the plasma torch plays a vital role for the plasma arc generation. The temperature of the arc is very high and at the electrode is around 3500°C. The cutting torch requires proper cooling system in order to prevent the electrode from quick wear due to the existence of high thermal gradient. The presented work aimed to study the impact of three coolants propylene glycol, ethylene glycol and de-ionized water flow over the electrode life. The experimental setups were arranged to study the heat transfer capabilities of the three coolants for different flow values and aimed to achieve the optimal flow rates for the efficient heat removal. The electrode life test trials were conducted to measure the electrode life for the flow values of three coolants in the temperature rise test. The optimal flow rates arrived from temperature rise test and the electrode life measured from life test are compared for the three coolant cases considered.

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Investigation of Bending Fatigue of Composite Plates by Using Infrared Thermography

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.268-270.406 ◽

2011 ◽

Vol 268-270 ◽

pp. 406-411 ◽

Cited By ~ 1

Author(s):

Ömer Sinan Şahin ◽

Murat Selek ◽

Şirzat Kahramanlı

Keyword(s):

Infrared Thermography ◽

Heat Generation ◽

Temperature Rise ◽

Epoxy Composite ◽

Composite Plates ◽

Fatigue Loading ◽

Thermal Camera ◽

Thermal Images ◽

Bending Fatigue ◽

Damage Initiation

In this study, the temperature rise of composite plates with a hole during fatigue loading was investigated. Woven glass/epoxy composite plates with eight plies were subjected to bending fatigue loading and materials were observed by using a thermal camera during the test. Previous works showed that a heat generation can form due to internal friction and damage formation. Therefore, a thermographic infrared imaging system was used to detect the temperature rise of composite specimens. During the tests, the thermal images of the specimens have been recorded by a thermal camera and then transferred to the image processing program which has been developed by using MATLAB. By using these thermal images, the spot temperatures of the specimen were obtained by using artificial neural networks. The obtained temperatures show local increase at places where the heat generation localized. These regions considered being the probable damage initiation sites. It is shown in this study that most probable damage initiation zones in the woven glass/epoxy composite material can be detected by using infrared thermography (IRT) approach prior to failure.

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RESIDUAL PLASTIC STRAIN STATE AND DELAMINATION PATTERN OF COMPOSITE LAMINATES WITH AUTOMATED INDUCED-GAP SUBJECTED TO HEMI-SPHERICAL IMPACT LOADING

10.12783/asc36/35790 ◽

2021 ◽

Author(s):

MOHAMMADHOSSEIN GHAYOUR ◽

MEHDI HOJJATI ◽

RAJAMOHAN GANESAN

Keyword(s):

Plastic Strain ◽

Impact Loading ◽

Residual Strain ◽

Composite Structures ◽

Strain State ◽

Composite Plates ◽

Structural Level ◽

Manufacturing Defects ◽

Initiation And Propagation ◽

The Impact

Automated manufacturing defects are types of composite structure defects that occur during fiber deposition by advanced robots. The induced gap is the most probable type of defect in the Automated Fiber Placement (AFP) technique. This defect can affect the mechanical performance of the composite structures at both material level by inducing the material inhomogeneity and the structural level by introducing the consolidation effect in the structure during the curing process. The current study investigates the effect of induced-gaps on the damage assessment of thin composite plates under Low-Velocity Impact (LVI) loading. The paper focuses on the delamination initiation and propagation and the residual plastic strain state of the impacted plates. The primary application of this study is to understand the interaction of induced gaps on the delamination pattern of composite samples subjected to LVI. For this purpose, a series of LVI tests are performed. Ultrasonic C-scan analysis and microscopic observation are implied to evaluate the internal damage due to impact loading. Finite Element (FE) analyses are then performed to evaluate the residual strain of the composite plates under Impact Energy (IE) loading less than 15 J. Then, the residual plastic strain in the impact zone is evaluated using a meso-macro method, and the effect of the local plasticity that occurs in the gap zones on the delamination initiation and propagation is studied. Results show that the stress relaxation due to the resin plasticity at the gap areas can affect the delamination pattern of the impacted composite plates. It is also shown that the residual strain of the impacted plates at the gap areas are new sources of the damages that need to be considered in the LVI analysis of the composite plates manufactured by the AFP technique.

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A Framework for Understanding Adaptation by Manufacturing Industries

Natural Resources Management ◽

10.4018/978-1-5225-0803-8.ch016 ◽

2017 ◽

pp. 302-313

Author(s):

Saon Ray

Keyword(s):

Climate Change ◽

Sea Level Rise ◽

Sea Level ◽

Temperature Rise ◽

Manufacturing Industries ◽

Climate Risk ◽

The Face ◽

Regulatory Barriers ◽

The Impact ◽

Medium Firms

This chapter discusses what constitutes adaptation responses by firms in the face of climate change. There are four integral components of adaptation activities undertaken by firms: assessment of risk, understanding of vulnerability, understanding the regulatory barriers to overcome the vulnerability, and, finally, adoption of policies to overcome the vulnerability. While it is easy to understand these components separately, their interdependencies make the overall picture more complicated. Also complicating the issue is the fact that most small and medium firms do not have the capacity and resources to predict the impact of such changes on their operations, and hence, to quickly make the adjustments necessary to overcome them. The response of firms also depends on the nature of the climate risk they face, whether it is sea-level rise, or temperature rise.

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Experimental Analysis for the Effect of Impactor Geometry on Carbon Reinforced Composite Materials

Polymers and Polymer Composites ◽

10.1177/096739111702500905 ◽

2017 ◽

Vol 25 (9) ◽

pp. 677-682 ◽

Cited By ~ 2

Author(s):

Faruk Elaldi ◽

Busra Baykan ◽

Can Akto

Keyword(s):

Composite Materials ◽

Carbon Fibre ◽

Composite Plates ◽

High Strength ◽

Low Velocity Impact ◽

Low Velocity ◽

Damage Area ◽

Reinforced Composite ◽

Contact Surfaces ◽

The Impact

For the last three decades, composites have become very preferable materials to be used in the automotive industry, structural parts of aircraft and military systems and spacecraft, due to their high strength and modulus. Composite materials are sometimes exposed to invisible or visible damage due to impact loading during their service life. In this study, the effect of impactor geometry with four different contact surfaces on woven carbon fibre-reinforced composite plates having three different thicknesses are investigated. In the first stage, composite plates were manufactured with the ply orientations of [45/-45/0/90/45/-45]2s, [45/-45/0/90/45/-45]3s, [45/-45/0/90/45/-45]4s based on conventional usage. In the second stage, carbon fibre-reinforced composite test panels were exposed to low velocity impact tests to obtain force-time, energy-time and force-displacement curves. Finally, semi and full penetration of composite panels and damage magnitude were determined. It was found that the impactor geometries with lower contact surfaces such as conical and ogive types were much more penetrative on composite plates than the other geometries, but they caused larger damage area in the vicinity of the impact point.

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Low Velocity Impact on Woven Kenaf Fiber Reinforced Composites

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.629.503 ◽

2014 ◽

Vol 629 ◽

pp. 503-506 ◽

Cited By ~ 3

Author(s):

Al Emran Ismail ◽

M.A. Hassan

Keyword(s):

Impact Velocity ◽

Composite Plates ◽

Fiber Reinforced Composites ◽

Low Velocity Impact ◽

Reinforced Composites ◽

Low Velocity ◽

Kenaf Fiber ◽

Velocity Impact ◽

The Impact ◽

Woven Kenaf

This paper presents the experimental investigations on the low velocity impact response of woven kenaf fiber reinforced composites. Kenaf yarns are weaved with an orientation of 00 of warp and 900 of weft to form woven kenaf mat. Three woven kenaf mats are stacked together to achieve the specified sequences. The woven stacked kenaf mats are hardened with polymeric resin and compressed to squeeze off any excessive resin and to minimize voids content. The hardened composite plates are perforated using different impact velocities. Impact responses of the composite plates are examined according to stacking sequences, impact velocities and fragmentation patterns. According to the present results, the impact strength is strongly related with the impact velocity. If higher impact velocity is used, the performances of load bearing are reduced. It is obvious that no significant features of composite fragmentations occurred from the perforated holes. However, relatively larger area of mechanical damages is found distributed around the holes, indicating the capability of composites to absorb energy effectively.

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