Influence of composition and crystal structure on the fracture toughness of NbCo2 Laves phase studied by micro-cantilever bending tests

A method of predicting the leak/rupture criteria for API 5L X80 and X100 linepipes was evaluated, based on the results of hydrostatic full-scale tests for X60, X65, X80 and X100 linepipes with an axially through-wall (TW) notch. The TW notch test results clarified the leak/rupture criteria, that is, the relationship between the initial notch lengths and the maximum hoop stresses during the TW notch tests. The obtained leak/rupture criteria were then compared to the prediction of the Charpy V-notch (CVN) absorbed energy-based equation, which has been proposed by Kiefner et al. The comparison revealed that the CVN-based equation was not applicable to the pipes having a CVN energy (Cv) greater than 130 J and flow stress greater than X65. In order to predict the leak/rupture criteria for these linepipes, the static absorbed energy for ductile cracking, (Cvs)i, was introduced as representing the fracture toughness of a pipe material. The (Cvs)i value was determined from the microscopic observation of the cut and buffed Charpy V-notch specimens after static 3-point bending tests. The CVN energy in the original CVN-based equation was replaced by an equivalent CVN energy, (Cv)eq’ which was defined as follows: (Cv)eq = 4.5 (Cvs)i. The leak/rupture criteria for the X80 and X100 linepipes with higher CVN energies were reasonably predicted by the modified equation using the (Cvs)i value.

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Seawater effects on static loads and interlayer cracking performance for polyvinyl chloride foam-cored sandwich composites

Advances in Mechanical Engineering ◽

10.1177/1687814018807342 ◽

2018 ◽

Vol 10 (11) ◽

pp. 168781401880734

Author(s):

Jian He ◽

Dongyuan Xie ◽

Qichao Xue ◽

Yangyang Zhan

Keyword(s):

Energy Release ◽

Polyvinyl Chloride ◽

Glass Fibre ◽

Critical Energy ◽

Bending Tests ◽

Rate Dependent ◽

Reinforced Plastic ◽

Glass Fibre Reinforced Plastic ◽

Glass Fibre Reinforced ◽

Cantilever Bending

The diffusion influence of seawater on the static and interlayer cracking properties of a polyvinyl chloride foam sandwich structure is investigated in this study. After soaking specimens in seawater for various durations, various comparison tests are performed to investigate the effects of seawater. Compression tests for H60 and H200 polyvinyl chloride foam specimens are conducted to study strength and modulus degradation, and the results show that immerging time and temperature have significant effects on polyvinyl chloride foam properties. Tensile tests for glass-fibre-reinforced plastic panels, four-point bending tests and double cantilever bending tests for polyvinyl chloride foam sandwich specimens are also performed. The results show that seawater immerging treatment has a noticeable influence on glass-fibre-reinforced plastic tensile properties and interlayer critical energy release rate values, but has almost no effect on bending properties of foam sandwich specimen. Furthermore, a rate-dependent phenomenon is observed in double cantilever bending tests, in which higher loading rate will lead to larger critical energy release values. Numerical simulation is also performed to illustrate the cracking process of double cantilever bending tests and shows a certain accuracy. The simulation also demonstrates that the viscoelasticity of foam material after immerging treatment results in the rate-dependent characterization of double cantilever bending tests.

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Effect of Nd, Pr substitutional atoms on the magnetic and magnetostrictive properties in (Tb-Dy)(Fe-Co)2 Laves phases

Journal of Physics Conference Series ◽

10.1088/1742-6596/2103/1/012196 ◽

2021 ◽

Vol 2103 (1) ◽

pp. 012196

Author(s):

G A Politova ◽

M A Ganin ◽

A B Mikhailova ◽

D A Morozov ◽

K E Pankov ◽

...

Keyword(s):

Crystal Structure ◽

Magnetic Properties ◽

Laves Phase ◽

Type Structure ◽

Partial Substitution ◽

Laves Phases ◽

Temperature Range ◽

Homogenizing Annealing ◽

Arc Melting ◽

Magnetostrictive Materials

Abstract Polycrystalline TbxDy1-xR0.1Fe2-zCoz (R = Nd, Pr, x = 0.2, 0.3; z = 0, 1.3) cubic Laves phase alloys with MgCu2-type structure were prepared by arc melting followed by homogenizing annealing. The crystal structure, magnetic properties, and magnetostriction have been investigated. Compounds with high values of magnetostrictive susceptibility were found in the temperature range 150-300 K. Compounds with partial substitution of cobalt for iron demonstrate a change in the sign of anisotropic magnetostriction. This work continues the search for magnetostrictive materials with inexpensive neodymium and praseodymium.

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Local Fracture Toughness and Residual Stress Measurements on NiAl Bond Coats by Micro Cantilever and FIB Based Bar Milling Tests

Superalloys 2012 ◽

10.1002/9781118516430.ch10 ◽

2012 ◽

pp. 93-102 ◽

Cited By ~ 2

Author(s):

Ralf Webler ◽

Markus Krottenthaler ◽

Steffen Neumeier ◽

Karsten Durst ◽

Mathias Göken

Keyword(s):

Fracture Toughness ◽

Residual Stress ◽

Local Fracture ◽

Bond Coats ◽

Stress Measurements ◽

Micro Cantilever

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Prediction of steel resistance to stress corrosion cracking in seawater based on accelerated tests and structural studies

E3S Web of Conferences ◽

10.1051/e3sconf/201912104009 ◽

2019 ◽

Vol 121 ◽

pp. 04009

Author(s):

Svetlana Mushnikova ◽

Oleg Kharkov

Keyword(s):

Structural Phase ◽

Real Life ◽

Austenitic Stainless Steels ◽

Test Results ◽

Mechanical Fracture ◽

Bending Tests ◽

Laboratory Test Results ◽

Resistance To Stress ◽

Concentrated Solution ◽

Cantilever Bending

The paper presents the tests results of resistance of various structural steel classes to SCC in chloride solutions. The experiments were performed using cantilever bending tests developed by NRC “Kurchatov Institute” – CRISM “Prometey” with stepwise increasing load of Charpy-type precracking specimens. The criterion estimation of resistance to SCC when β = σSCC/σC > 0.85 was confirmed by the laboratory test results compared with the case studies of corrosion-mechanical fracture of shipbuilding structures in real life service conditions. A new approach of SCC susceptibility of austenitic stainless steels in marine conditions is proposed. It is based on estimation of the critical temperature of SCC when testing for SSRT in a concentrated solution of calcium chloride at temperatures from 20°C to 100°C. Specific features of the structural-phase composition of steels that detrimentally affect the resistance to SCC were discovered during the complex testing.

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