Cavitation Erosion Mechanism Based on Analysis of Erosion Particles

2008 ◽  
Vol 130 (3) ◽  
Author(s):  
A. Abouel-Kasem ◽  
S. M. Ahmed
Keyword(s):  
Early Detection ◽  
Surface Morphology ◽  
Failure Mode ◽  
Cavitation Erosion ◽  
Pure Aluminum ◽  
Incubation Stage ◽  
Erosion Mechanism ◽  
Large Size ◽  
Closed Systems ◽  
Lamellae Structure

The mechanism of cavitation erosion is investigated in detail through observations of the removed particles from pure aluminum (Al-99.999). The particles removed during the incubation stage have distinctive characteristics compared to those removed in the subsequent stages. These characteristics are distinguished by lamellae structure, foldness, waviness, large size as well as one of the particle surfaces appeared to be part of the original face of the specimen. Therefore, these characteristics can be used as a monitor for early detection of cavitation erosion in closed systems. Systematic observations of disloged particles and eroded surface morphology show that the dominant failure mode in cavitation erosion is fatigue.

Hygrothermal Behavior of T700 and T300 BMI Used for Advanced Polymeric Composite

2012 ◽  
Vol 476-478 ◽  
pp. 632-635 ◽  
Author(s):  
Shuang Wang ◽  
Wei Fang Zhang ◽  
Yu Chen ◽  
Yu Fen Wu
Keyword(s):  
Compressive Strength ◽  
Glass Transition ◽  
Transition Temperature ◽  
Glass Transition Temperature ◽  
Surface Morphology ◽  
Water Absorption ◽  
Failure Mode ◽  
Polymeric Composite ◽  
Compressive Properties ◽  
Hygrothermal Behavior

The mechanism of hydrothermal ageing was investigated for T700/ BMI 5428 and T300/QY8911 by studying its glass transition temperature, tensile/compressive properties, changes of surface morphology absorbed in water with 100°C temperature. Results show that the glass transition temperature getting lower with the rate of water absorption. The tensile/compressive strength of composite decreased in the humid and heat environments, although with the identical failure mode.

Failure Mode Investigation for Blue Polymer EL Device

2006 ◽  
Vol 937 ◽  
Author(s):  
Mu-Gyeom Kim ◽  
Sang Yeol Kim ◽  
Tae Woo Lee ◽  
Sang Hun Park ◽  
Ju Cheol Park ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Failure Mode ◽  
Bond Cleavage ◽  
Major Effect ◽  
Anode Side ◽  
Cleavage Process ◽  
Tof Sims ◽  
Migration Mechanism ◽  
Ft Ir ◽  
Non Destructive

ABSTRACTWe report the failure mode observed in polymer EL blue device. Such modes were analyzed by non-destructive and destructive ways. As a non-destructive way, investigation of mobility changes of hole and electron, measuring transient EL corresponding to life curve, had been done. We also observed compositional and morphological variation using TEM-EDX, STM, FT-IR, TOF-SIMS and reverse engineering method as a destructive way. Electron mobility has a higher dependency on life curve, which fact could be reflected on the formation of insoluble layer inside emitting layer on anode side. And such insoluble layer showed relatively ordered surface morphology, and might be a cross-linked layer through C-O-C bond cleavage process while EL operation. But, contrary to sulfur migration mechanism into insoluble layer insisted by CDT, we did confirm no obvious difference of sulfur composition between insoluble and emitting layers. Rather, there's some degree of Ba diffusion into emitting layer from decomposition of BaF2, but, which dose not have a major effect on device degradation.

Investigation Into Cavitation Erosion Pits

2009 ◽  
Vol 131 (3) ◽  
Author(s):  
A. Abouel-Kasem ◽  
A. Ezz El-Deen ◽  
K. M. Emara ◽  
S. M. Ahmed
Keyword(s):  
Stainless Steel ◽  
Cavitation Erosion ◽  
Pure Aluminum ◽  
The Other ◽  
304 Stainless Steel ◽  
Testing Time ◽  
Limited Effect ◽  
Fatigue Process

Cavitation erosion pits and their effects on erosion progression were investigated in detail for SUS 304 stainless steel, α+β brass (60/40), and pure aluminum (Al-99.999 and Al-99.92) by means of vibratory erosion. Two kinds of erosion pits were found on the specimen surfaces, one by microjet impact and the other by shockwave blow. Systematic observations of the feature of microjet-pits with the testing time showed that the sizes and shapes of microjet-pits did not change at all and such pits scarcely played an important role in developing the erosion. Moreover, the feature morphology of eroded surfaces, and dislodged particles and their large sizes revealed that microjet-pits had a limited effect on erosion and that the predominant failure was a fatigue process.

Cavitation Erosion of HVOF Coatings

1996 ◽  
Author(s):  
R. Schwetzke ◽  
H. Kreye
Keyword(s):  
Erosion Rate ◽  
Cavitation Erosion ◽  
Metallic Alloys ◽  
Erosion Mechanism ◽  
Hvof Coatings ◽  
Coating Composition ◽  
Before And After ◽  
Series Of Experiments ◽  
The Individual ◽  
Scanning Electron

Abstract The proposed paper reports a series of experiments to investigate the cavitation erosion mechanism of HVOF coatings. Vibratory cavitation erosion tests according to ASTM G 32 have been carried out with several HVOF coatings including cermets, oxides and metallic alloys. The steady state erosion rate for each coating was determined and the effect of coating composition and microstructure on the erosion rate was investigated. The morphology and microstructure of the various coatings before and after cavitation testing were analyzed by means of light optical and scanning electron microscopy in order to study the erosion mechanism. The results demonstrate that HVOF coatings of NiCrFeBSi, WC-17Co, Cr3C2-25NiCr and Cr2O3 can exhibit a rather high resistance against cavitation erosion and should be considered for application as a protective surface layer against cavitation. Furthermore, it is shown that cavitation testing can provide a useful tool to study and characterize the bond strength between individual splats as well as the brittleness of the individual phases present in the coating.

scholarly journals Mechanical Respond and Failure Mode of Large Size Honeycomb Sandwiched Composites under In-Plane Shear Load

Molecules ◽  
2019 ◽  
Vol 24 (23) ◽  
pp. 4248 ◽  
Author(s):  
Wang ◽  
Wang ◽  
Liu ◽  
Zhang ◽  
Wan ◽  
...  
Keyword(s):  
Theoretical Analysis ◽  
Shear Strain ◽  
Failure Mode ◽  
Field Distribution ◽  
Shear Failure ◽  
Buckling Load ◽  
Analysis Method ◽  
Plane Shear ◽  
Large Size ◽  
Honeycomb Sandwich

The present work focuses on the in-plane shear respond and failure mode of large size honeycomb sandwich composites which consist of plain weave carbon fabric laminate skins and aramid paper core. A special size specimen based on a typical element of aircraft fuselage was designed and manufactured. A modified in-plane shear test method and the corresponding fixture was developed. Three large size specimens were tested. The distributed strain gauges were used to monitor the mechanical response and ultimate bearing capacity. The results show that a linear respond of displacement and strain appears with the increase of the load. The average shear failure load reaches 205.68 kN with the shear failure occurring on the face sheet, and the maximum shear strain monitored on the composite plate is up to 16,115 με. A combination of theoretical analysis and finite element method (FEM) was conducted to predict the shear field distribution and the overall buckling load. The out-of-plane displacement field distribution and in-plane shear strain field distribution under the pure shear loading were revealed. The theoretical analysis method was deduced to obtain the variation rule of the shear buckling load. A good agreement was achieved among the experiment, theoretical analysis, and FEM results. It can be concluded that the theoretical analysis method is relatively conservative, and the FEM is more accurate in case of deformation and strain. The results predicted by h element and p element methods are very close. The results of the study could provide data support for the comprehensive promotion of the design and application of honeycomb sandwich composites.

Cavitation erosion mechanism of NiTi coatings made by laser plasma hybrid spraying

Wear ◽  
1999 ◽  
Vol 231 (2) ◽  
pp. 272-278 ◽  
Author(s):  
Hitoshi Hiraga ◽  
Takashi Inoue ◽  
Hirofumi Shimura ◽  
Akira Matsunawa
Keyword(s):  
Laser Plasma ◽  
Cavitation Erosion ◽  
Erosion Mechanism

scholarly journals Nanobodies: a tool to open new horizons in diagnosis and treatment of prostate cancer

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Maryam Hosseindokht ◽  
Hamid Bakherad ◽  
Hamed Zare
Keyword(s):  
Prostate Cancer ◽  
Early Detection ◽  
Cancer Cells ◽  
Target Therapy ◽  
Main Body ◽  
Prostate Cancer Cells ◽  
New Horizons ◽  
Large Size ◽  
Cancer Antigens ◽  
Specific Antigens

Abstract Background Prostate cancer is one of the most common cancers in men and its incidence has increased dramatically in the last decade. This increase in the detection of this type of cancer is based more on the detection of PSA or PSMA antigens as the most important specific antigens of this cancer, and this early detection has greatly helped in the more optimal treatment of patients. Main body Many methods have been proposed by researchers for early detection of prostate cancer, but most of the methods used today to detect this type of cancer have been using classical antibodies. Although classical antibodies are able to detect tumor cell markers, but instability, large size, costly and laborious production, and random immobility characteristics, causes many problems. Nanobodies or VHHs, which are derived from camel heavy chain antibodies, have special advantages and have eliminated the disadvantages of classical antibodies which makes them attractive to use in biosensors and cancer diagnostic kits. The research that has been done so far shows that the introduced nanobodies are created for the purpose of targeting, detecting and sensing prostate cancer cells with two main purposes. The first is the efficient identification of prostate cancer and the second is the elimination of cancer cells. Conclusion Research shows the use of specific nanobodies against prostate cancer antigens in the design of biosensors and target therapy will be very interesting. In this review article, these nanobodies are introduced and categorized based on their performance.

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