scholarly journals FRP for Marine Application

2021 ◽  
Author(s):  
Bikash Chandra Chakraborty
Keyword(s):  
Vinyl Ester ◽  
Sea Water ◽  
Superposition Principle ◽  
Marine Corrosion ◽  
Sulfate Reducing ◽  
Specific Strength ◽  
Reinforced Plastics ◽  
Marine Application ◽  
Reinforced Cement ◽  
Time Temperature Superposition Principle

Fiber Reinforced Plastics (FRPs) are widely used in marine sector owing to their high specific strength and resistance to marine corrosion. For naval application, additional advantages are transparency to radar wave and better vibration damping than metals. The use of various FRPs in off-shore structures and marine vessels needs analysis of desired properties considering the types of matrices and fiber. The common consideration is effect of sea water on the properties of the FRP. This chapter gives a brief on use of different FRPs in various areas such as off-shore pillars, Reinforced Cement Concrete (RCC) enclosers, primary and secondary marine components. A brief discussion is included here on diffusion models and estimation of durability by a time-temperature superposition principle applied to water ingress and corresponding change in mechanical strength of FRPs with examples. The effect of microbial activity on the damage of FRP is not very much reported in literature. It is known that sulfate-reducing bacteria (SRB) are the most damaging microbes for FRP. In conclusion, it is highlighted that vinyl-ester-based FRPs using glass and carbon fibers are best for marine application. To determine the realistic service life in marine environment, Vinyl Ester- FRP (VE-FRP) are to be simultaneously studied for damage due to sea water and the microbes such SRB.

An Alteration of the Time-Temperature Superposition Principle to Account for Environmental Degradation in Fibre Reinforced Plastics

2018 ◽  
Vol 923 ◽  
pp. 22-28
Author(s):  
Etienne Kolomoni Ngoy
Keyword(s):  
Environmental Degradation ◽  
Superposition Principle ◽  
Temperature Shift ◽  
Additional Term ◽  
Shift Factor ◽  
Basic Material ◽  
Material Strength ◽  
Reinforced Plastics ◽  
Prediction Test ◽  
Time Temperature Superposition Principle

The approach suggested in this analysis stems from basic material science laws and considers that any environmental degradation of polymer composites ultimately consists in chemical link and cohesion force alteration. Such alteration leads to the modification of material viscoelastic characteristics that can be measured through stress relaxation or creep. Then the analysis deals with the applicability of the time-temperature shift principle for prediction test in cases involving environmental degradation. It is demonstrated that the shift factor as determined from Arrhenius Law needs to incorporate an additional term to account for the variation of the activation energy of the chemical and physical degradation. The method leads to excellent prediction of the time and environment dependent material strength.

Integration of Atomistic Simulation with Experiment Using Time−Temperature Superposition for a Cross-Linked Epoxy Network

2019 ◽  
Author(s):  
Ketan Khare ◽  
Frederick R. Phelan Jr.
Keyword(s):  
Master Curve ◽  
Glassy State ◽  
Superposition Principle ◽  
Quantitative Comparison ◽  
Time Shift ◽  
Data Sets ◽  
Epoxy Network ◽  
Temperature Superposition ◽  
Time Temperature Superposition ◽  
Time Temperature Superposition Principle

<a></a><a>Quantitative comparison of atomistic simulations with experiment for glass-forming materials is made difficult by the vast mismatch between computationally and experimentally accessible timescales. Recently, we presented results for an epoxy network showing that the computation of specific volume vs. temperature as a function of cooling rate in conjunction with the time–temperature superposition principle (TTSP) enables direct quantitative comparison of simulation with experiment. Here, we follow-up and present results for the translational dynamics of the same material over a temperature range from the rubbery to the glassy state. Using TTSP, we obtain results for translational dynamics out to 10<sup>9</sup> s in TTSP reduced time – a macroscopic timescale. Further, we show that the mean squared displacement (MSD) trends of the network atoms can be collapsed onto a master curve at a reference temperature. The computational master curve is compared with the experimental master curve of the creep compliance for the same network using literature data. We find that the temporal features of the two data sets can be quantitatively compared providing an integrated view relating molecular level dynamics to the macroscopic thermophysical measurement. The time-shift factors needed for the superposition also show excellent agreement with experiment further establishing the veracity of the approach</a>.

Corrosion Behaviors of 0Cr18Ni9 Stainless Steel under the Combination Action of Sulfate-Reducing Bacteria and V.natriegens

2011 ◽  
Vol 356-360 ◽  
pp. 161-164
Author(s):  
Cai Xiang Gu ◽  
Xiao Ming Zhao ◽  
Yan Sheng Yin ◽  
Gui Jun Ji
Keyword(s):  
Stainless Steel ◽  
Corrosion Potential ◽  
Sea Water ◽  
Microbial Corrosion ◽  
Sulfate Reducing ◽  
Facultative Anaerobic ◽  
Corrosion Behaviors ◽  
Microbial Film ◽  
Combined Action ◽  
Reducing Bacteria

Advantage strains SRB and V.natriegens were obtained from the China East Sea for this study. Polarization curves, corrosion potential, scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) analyses were adopted in order to investigate the corrosion behaviors of 0Cr18Ni9 stainless steel under the combination action of anaerobic SRB and facultative anaerobic V.natriegens, The characteristics and mechanisms of microbial corrosion action in sea water were analyzed in this paper. The results show that SRB and V.natriegens promote each other’s growth when cultivated in the mixed microbe medium, in which the rate of corrosion is higher than that in the single microbe; Under the combined action of the mixed microbe, the microbial film gets wider and thicker, and corrosion products and metabolite are produced, which furthermore accelerates the passivation and pit corrosion to the 0Cr18Ni9 stainless steel.

Sign in / Sign up

Export Citation Format

Share Document