scholarly journals Influence of the polymer matrix type on cavitation resistance of composites

2021 ◽  
Vol 46 (1) ◽  
pp. 31-34
Author(s):  
Marina Dojčinović ◽  
Marko Pavlović ◽  
Slađana Jezdimirović ◽  
Branka Purić ◽  
Aleksandar Cvetković
Keyword(s):  
Electron Microscopy ◽  
Polymer Matrix ◽  
Polyester Resin ◽  
Surface Damage ◽  
Powder Composite ◽  
Test Time ◽  
Cavitation Resistance ◽  
Matrix Type ◽  
Powder Composites ◽  
Scanning Electron

Cavitation resistance of polymer matrix / basalt powder composites was determined in this work. Two types of composites were tested: epoxy resin / basalt powder composite and polyester resin / basalt powder composite. In both cases, a basalt powder was used as reinforcement in the resin (grain size 20μm, in the amount of 15 wt%). An ultrasonic vibration method with a stationary sample was used to test the cavitation resistance of composites in laboratory conditions. The change in sample mass with test time was monitored to define cavitation rate. Scanning electron microscopy was used to monitor the morphology of composites surface damage.

scholarly journals Determination of resistance to cavitation of pyrophyllite samples

2021 ◽  
Vol 62 (2) ◽  
pp. 126-134
Author(s):  
Ljubiša Andrić ◽  
Marko Pavlović ◽  
Marina Dojčinović ◽  
Dragan Radulović
Keyword(s):  
Electron Microscopy ◽  
Cavitation Erosion ◽  
Surface Damage ◽  
Test Method ◽  
Test Time ◽  
Cavitation Resistance ◽  
Initial Sample ◽  
Erosion Test ◽  
Scanning Electron

The resistance under the action of cavitation of sintered pyrophillite samples was investigated. The initial sample of pyrophillite from the Parsovic-BiH deposit was ground a vibrating mill to a granulation of 20 mm, pressed and sintered at temperatures (⁰C): 100; 1100; 1200. To assess cavitation resistance, the change in sample mass as a function of cavitation time was monitored. The cavitation erosion test was performed using the ultrasonic vibratory cavitation test method according to the ASTM G-32 standard. Cavitation velocites were calculated for all samples, as a basic indicator of the resistance of the material under the action of cavitation. The change in the morphology of the surface with the test time was followed by scanning electron microscopy. Based on the values of cavitation velocity and analysis of the surface damage morphology, the cavitation resistance of the tested samples based on pyrophillite was determined. The obtained results indicate that the samples of sintered pyrophillite have satisfactory resistance to the action of cavitation and be applied in conditions of lower cavitation loads.

Effects of Trans-Polyoctylene Rubber in Polypropylene/Recycled Acrylonitrile Butadiene/Rice Husk Powder Composites

2013 ◽  
Vol 594-595 ◽  
pp. 613-617
Author(s):  
Santiagoo Ragunathan ◽  
Sung Ting Sam ◽  
Abdul Ghani Azlinda ◽  
Hussin Kamaruddin ◽  
Ismail Hanafi ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Rice Husk ◽  
Butadiene Rubber ◽  
Rotor Speed ◽  
Good Adhesion ◽  
Rubber Composite ◽  
Powder Composites ◽  
Internal Mixer ◽  
Scanning Electron

Composites of polypropylene/Acylonitrile butadiene rubber/Rice husk powder/ (PP/NBRr/RHP) with and without trans-polyoctylene rubber (TOR) were prepared, and the effects of trans-polyoctylene rubber were investigated. By using rice husk powder of 150300μm, five different compositions of PP/NBRr/RHP composites (i.e.100/0, 80/20, 70/30, 60/40 and 40/60 phr) were prepared in an internal mixer at 180 °C and 50 rpm rotor speed. The results indicate that the incorporation of TOR improved the tensile properties of PP/NBRr/RHPcomposites. Scanning electron microscopy of the fractured surfaces proved that TOR promoted good adhesion between the PP-NBRr matrices and RHP.Keywords: Polypropylene; Trans-polyoctylene rubber; Rice husk powder; Acrylonitrile Butadiene rubber; composite

Kaolinite dispersion in cassava starch-based composite films: a photonic microscopy and X-ray tomography study

2018 ◽  
Vol 38 (7) ◽  
pp. 641-647
Author(s):  
Jean Aimé Mbey ◽  
Fabien Thomas ◽  
Sandrine Hoppe
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Dimethyl Sulfoxide ◽  
Polymer Matrix ◽  
Composite Films ◽  
Cassava Starch ◽  
X Ray ◽  
Clay Dispersion ◽  
Combined Use ◽  
Scanning Electron

Abstract In the present study, a combined use of photonic microscopy, scanning electron microscopy and 3D X-ray tomography is carried out in order to analyze the dispersion and the distribution of raw and dimethyl sulfoxide (DMSO)-intercalated kaolinite used as filler in cassava starch-based films. It is shown that the association of these techniques allows a valuable analysis of clay dispersion in polymer-clay composite films. In the case of kaolinite-starch composite films on which this study is focused, it is obvious that previous intercalation of kaolinite with DMSO is an efficient way to improve dispersion and distribution of kaolinite in a starch polymer matrix.

scholarly journals Thermal properties of porcelain reinforced polyester resin composites

2017 ◽  
Vol 52 (2) ◽  
pp. 147-152
Author(s):  
R Sultana ◽  
R Akter ◽  
MR Qadir ◽  
MA Gafur ◽  
MZ Alam
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermal Properties ◽  
Polyester Resin ◽  
Compression Molding ◽  
Resin Composites ◽  
Thermal Stabilities ◽  
Degradation Temperature ◽  
Scanning Electron ◽  
Thermal Conductivities

Porcelain reinforced polyester resin composites (PPCs) having different compositions have been prepared by compression molding. Thermal properties of PPCs were studied by means of TG-DTA and TMA. The influence of porcelain content on thermal properties of PPCs was studied in detail. Thermal conductivities of PPCs decreased from 0.00068 cal/cm sec°C to 0.00030 cal/cm sec°C by the addition of porcelain from 10 to 60%. The results of this study reveal their good thermal stabilities. The 50% degradation temperature of pure Polyester resin was 401.5°C, but that of the PPC-1, PPC-2 and PPC-4 were 406.3°C, 407.8°C, and 417.3°C respectively. The morphology of the composites was studied with scanning electron microscopy (SEM).Bangladesh J. Sci. Ind. Res. 52(2), 147-152, 2017

scholarly journals Mechanisms and morphologies of cavitation damage of NN 70 steel

2021 ◽  
Vol 62 (2) ◽  
pp. 95-105
Author(s):  
Vujadin Aleksić ◽  
Marina Dojčinović ◽  
Ljubica Milović ◽  
Bojana Zečević ◽  
Ana Maksimović
Keyword(s):  
Fatigue Testing ◽  
Low Cycle Fatigue ◽  
Surface Damage ◽  
Parent Material ◽  
Resistance Testing ◽  
Test Time ◽  
Cavitation Resistance ◽  
Cavitation Damage ◽  
Damage Monitoring ◽  
Sample Method

Broken test tubes for low-cycle fatigue testing of Nionicral 70 (NN-70) parent material (PM) steel and simulated heat-affected zones (SHAZ) were used to produce samples for cavitation resistance testing. Ultrasonic vibrational cavitation method (stationary sample method) was applied for testing in laboratory conditions. The test conditions and procedure, sample preparation and interpretation of results are defined by ASTM G32. The surfaces of the NN-70 PM and SHAZ steel samples were exposed to cavitation and damage monitoring over time. Measuring the weight loss of samples on the analytical balance after a certain time allowed us to determine the cavitation velocity as a measure of the material's resistance to the effect of cavitation. Scanning electron microscopy (SEM) was applied to monitor variations in surface morphology with changing test time. On the basis of the results of the cavitation resistance test, the morphologies of the surface damage for different exposure times of the cavitation of PM and SHAZ steel NN-70 samples were analyzed, as well as the mechanisms that led to the damage of the sample surfaces.

Morphological Characterization of a Sustained-Release Drug Implant by Scanning Electron Microscopy, Polarized Light Microscopy and Image Analysis

1998 ◽  
Vol 4 (S2) ◽  
pp. 932-933
Author(s):  
J.P. Neilly ◽  
J.S. Deng ◽  
J.L. House ◽  
J.A. Fagerland
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sustained Release ◽  
Light Microscopy ◽  
Polymer Matrix ◽  
Polarized Light ◽  
Polarized Light Microscopy ◽  
Sustained Drug Release ◽  
Gentamicin Sulfate ◽  
Scanning Electron

Septacin is a sustained-release antibiotic currently under development by the Hospital Products Division of Abbott Laboratories. The product is designed to be used as an anti-infective implant in orthopedic surgical procedures with a sustained drug release for up to six weeks in vivo. It consists of gentamicin sulfate formulated with a bioerodable polyanhydride copolymer. The polymer is biodegradable and has been approved by the FDA for human clinical trials. The final product is obtained by mixing 20% gentamicin sulfate with molten polymer and injection molding it to form cylindrical Septacin beads.The microstructure of drug particles and polymer matrix is critical to the performance of sustained release products, thus scanning electron microscopy (SEM) and polarized light microscopy (PLM) were utilized in this study. SEM has proven useful for evaluating the microstructure of drug formulations3 and was used to examine the drug-polymer matrix structure. Average drug particle size and distribution were determined, and the drug-polymer boundary was evaluated.

Study on the modification of polyester resin bamboo fiber-based composite with euphorbia coagulum and their effect on mechanical and thermal properties

2020 ◽  
Vol 54 (24) ◽  
pp. 3473-3480 ◽  
Author(s):  
Sanju Kumari ◽  
Ritesh Kumar ◽  
Bhuvneshwar Rai ◽  
Sidhharth Sirohi ◽  
Gulshan Kumar
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Thermogravimetric Analysis ◽  
Water Absorption ◽  
Polymer Blend ◽  
Polyester Resin ◽  
Bamboo Fiber ◽  
Synthetic Fiber ◽  
Mechanical And Thermal Properties ◽  
Scanning Electron

Environmental problems caused by extensive use of polymeric materials can be solved by replacing the synthetic petroleum-based resins with natural biodegradable resins, and synthetic fiber with natural plant fiber. The blend based on euphorbia coagulum and polyester resin with different ratio of both the polymers is produced. In the polymer blend, methyl ethyl ketone peroxide used as an initiator and cobalt naphthenate as an accelerator was added. Bamboo fiber was incorporated into the polymer blend as the natural filler to fabricate composite. Herein, untreated as well as alkali treated bamboo fiber was used to fabricate the composite. Alkali treatment enhanced the compatibility between the polymer blend and the fiber. To evaluate the properties of composites, water absorption, scanning electron microscopy, mechanical test, thermogravimetric analysis, and infrared spectroscopy have been performed. Scanning electron microscopy analysis of composite shows better interlocking between the polymer blend and the fiber. The maximum enhancement in mechanical properties were observed in composite with 30% euphorbia coagulum such as tensile strength, Young’s modulus, flexural strength, and impact strength were increased up to 11%, 48%, 8%, and 60%, respectively, and water absorption decreased up to 47%. Thermogravimetric analysis and differential scanning calorimetry analysis of composite with 30% euphorbia coagulum show enhanced thermal stability up to 8%. Composite material developed was ecofriendly and can be useful for the multipurpose panel, beam, and pedestrian bridge and can replace petroleum products.

Water damage in polyester resins

1967 ◽  
Vol 300 (1463) ◽  
pp. 415-419 ◽  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Pressure ◽  
Electron Probe ◽  
Polyester Resin ◽  
Water Soluble ◽  
Stress Distributions ◽  
Polyester Resins ◽  
X Ray ◽  
Scanning Electron

The nature of cracks, produced in three cured polyester resins during exposure to water has been studied by the combined techniques of optical microscopy, scanning electron microscopy and electron probe X-ray microanalysis. There are many cracks totally enclosed within the resin and it is shown that these must be attributed to pockets of high pressure produced at impurity inclusions by interaction with water : in most cases, osmotic pressure from water soluble inorganic inclusions. The distribution and orientation of cracks gives evidence of relatively complex laminar stress distributions generated by water exposure in a polyester resin plate. There can be a laterally compressive stress in the interior of a plate, with laterally tensile stress at or nearer to the surface. It is pointed out that the interactions of water with a cured polyester resin have the necessary complexity to generate such stress systems since the first effects, water uptake and hydrolysis, causing swelling, also enhance molecular mobility and can promote further double-bond polymerization, accompanied by shrinkage.

Mechanisms of Wear of Sintered Carbide Dental Burs

1980 ◽  
Vol 102 (4) ◽  
pp. 560-565 ◽  
Author(s):  
J. Larsen-Basse
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
High Temperature ◽  
Thermal Fatigue ◽  
Wear Mechanisms ◽  
Applied Load ◽  
Surface Damage ◽  
Binder Removal ◽  
Scanning Electron ◽  
Dental Burs

A study of worn cemented carbide dental burs was undertaken by scanning electron microscopy. Some worn burs were obtained from practicing dentists and others were worn in the laboratory against the enamel of extracted teeth. The wear mechanisms observed depend strongly on applied load and degree of cooling. As the applied load is increased the following mechanisms gradually come into play: polishing of carbide grains, preferential binder removal, uprooting of carbide grains near edges, and fragmentation of carbide grains and removal of the fragments. In addition, under conditions of heavy loading and absence of cooling thermal fatigue becomes a factor and wear by diffusion into and erosion by a high temperature film of dental material becomes important. The wear initiates at points of severe surface damage caused by the grinding operation during manufacture.

Sign in / Sign up

Export Citation Format

Share Document