Solidification Cracking Assessment of LTT Filler Materials by Means of Varestraint Testing and µCT

Investigations of the weldability of metals often deal with hot cracking, as one of the most dreaded imperfections during weld fabrication. The hot cracking investigations presented in this paper were carried out as part of a study on the development of low transformation temperature (LTT) weld filler materials. These alloys allow to mitigate tensile residual stresses that usually arise during welding using conventional weld filler materials. By this means, higher fatigue strength and higher lifetimes of the weld can be achieved. However, LTT weld filler materials are for example, high-alloyed Cr/Ni steels that are susceptible to the formation of hot cracks. To assess hot cracking, we applied the standardized modified varestraint transvarestraint hot cracking test (MVT), which is well appropriate to evaluate different base or filler materials with regard to their hot cracking susceptibility. In order to consider the complete material volume for the assessment of hot cracking, we additionally applied microfocus X-ray computer tomography (µCT). It is shown that by a suitable selection of welding and MVT parameter the analysis of the complete 3D hot crack network can provide additional information with regard to the hot cracking model following Prokhorov. It is now possible to determine easy accessible substitute values (e.g., maximum crack depth) for the extent of the Brittleness Temperature Range (BTR) and the minimum critical strain P m i n .

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Numerical simulation of nickel-based alloys’ welding transient stress using various cooling techniques

High Temperature Materials and Processes ◽

10.1515/htmp-2020-0067 ◽

2020 ◽

Vol 39 (1) ◽

pp. 633-644

Author(s):

Meng He ◽

Jianing Qi ◽

Zhentai Zheng ◽

Fen Shi ◽

Yunfeng Lei

Keyword(s):

Compressive Stress ◽

Hot Cracking ◽

Von Mises Stress ◽

Transient Stress ◽

Hot Crack ◽

High Temperature Alloys ◽

Cooling Intensity ◽

Von Mises ◽

Combined Cooling ◽

Selection Of

AbstractNickel-based alloys play an important role in the field of high-temperature alloys, which are widely used in nuclear reactors, aerospace and components of turbomachinery. However, the high susceptibility of welding hot crack is a main shortcoming to nickel-based alloys. One of the methods that reduce hot cracking susceptibility is by adjusting element constitution of weld metal and another method is by reducing transient stress. This article used finite element method to study the effect of cooling source on transient stress of the nickel-based alloy weld joint. The selection of appropriate cooling technique can decrease the peak of the transient von Mises stress and make the tensile stress turn into compressive stress, which is beneficial to reduce hot cracking susceptibility. The peak of the transient von Mises stress decreases as the cooling intensity increases from 0 to 15,000 W/m2 K, but increases if the cooling intensity is ineffective. When the distance between cooling source and heat source reaches 35 mm, the weld can get larger region of compressive stress. The peak of the transient von Mises stress decreases with increasing radius of cooling source and reaches minimum value at 12 mm. Combined cooling is more effective in reducing the peak of this stress than the conventional single trailing cooling source.

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Marketing Literature Review

Journal of Marketing ◽

10.1509/jmkg.64.3.102.18031 ◽

2000 ◽

Vol 64 (3) ◽

pp. 102-114

Author(s):

Myron Leonard

Keyword(s):

Literature Review ◽

Database Marketing ◽

Marketing Literature ◽

Additional Information ◽

Ann Arbor ◽

Literature Database ◽

Selection Of

This section is based on a selection of article abstracts from a comprehensive business literature database. Marketing-related abstracts from over 125 journals (both academic and trade) are reviewed by JM staff. Descriptors for each entry are assigned by JM staff. Each issue of this section represents three months of entries into the database. JM thanks UMI for use of the ABI/INFORM business database. Each entry has an identifying number. Cross-references appear immediately under each subject heading. The following article abstracts are available online from the ABI/INFORM database, which is published and copyrighted by UMI. For additional information about access to the database or about obtaining photocopies of the articles abstracted here, please call (800) 626-2823 or write to UMI, 300 N. Zeeb Rd., Ann Arbor, MI 48106.

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Classical (Local and Contextual) Probability Model for Bohm–Bell Type Experiments: No-Signaling as Independence of Random Variables

Entropy ◽

10.3390/e21020157 ◽

2019 ◽

Vol 21 (2) ◽

pp. 157 ◽

Cited By ~ 19

Author(s):

Andrei Khrennikov ◽

Alexander Alodjants

Keyword(s):

Conditional Probability ◽

Probability Model ◽

Hidden Variables ◽

Random Variables ◽

Experimental Scheme ◽

Model Following ◽

No Signaling ◽

Independence Of Random Variables ◽

Main Message ◽

Selection Of

We start with a review on classical probability representations of quantum states and observables. We show that the correlations of the observables involved in the Bohm–Bell type experiments can be expressed as correlations of classical random variables. The main part of the paper is devoted to the conditional probability model with conditioning on the selection of the pairs of experimental settings. From the viewpoint of quantum foundations, this is a local contextual hidden-variables model. Following the recent works of Dzhafarov and collaborators, we apply our conditional probability approach to characterize (no-)signaling. Consideration of the Bohm–Bell experimental scheme in the presence of signaling is important for applications outside quantum mechanics, e.g., in psychology and social science. The main message of this paper (rooted to Ballentine) is that quantum probabilities and more generally probabilities related to the Bohm–Bell type experiments (not only in physics, but also in psychology, sociology, game theory, economics, and finances) can be classically represented as conditional probabilities.

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Soil gas physical-chemistry survey for geothermal exploration at Terceira Island, Azores.

10.5194/egusphere-egu2020-11845 ◽

2020 ◽

Author(s):

Claudia Rodríguez-Pérez ◽

Alba Martín-Lorenzo ◽

Fátima Rodríguez ◽

Gladys V. Melián ◽

María Asensio-Ramos ◽

...

Keyword(s):

Hydrothermal Activity ◽

Soil Gas ◽

Volcanic Complex ◽

Additional Information ◽

Geothermal Potential ◽

Potential Success ◽

Exploratory Wells ◽

To Receive ◽

Selection Of

Terceira Island is located in the Azores Archipelago and it lies at the intersection of four submarine volcanic ridges.&#160;Due to its characteristics the geothermal potential of Terceira Island has begun to receive some interest from researchers and decision makers from the 70s of last century, but only in 2000 an exploration license was granted in favour of GEOTERCEIRA (now EDA RENOV&#193;VEIS S.A.). The area of this license is located in the central part of the island in the Pico Alto Volcanic Complex, and includes the fumarolic field of Furnas do Enxofre.The main aim of this study is to provide additional information about the presence of fluids upflow regions and areas of increased subsurface permeability related to high temperature hydrothermal activity at depth, as part of an study to expand the current geothermal plant of Terceira. To achieve this objective, a soil gas and diffuse CO2 and H2S degassing survey, which included in situ CO2 emission measurements and soil temperature at 15 and 40 cm deep and the collection of soil gas samples, was performed during September 2019. 122 sampling sites were selected spaced at ~100 meters at Pico Alto Volcanic Complex. Diffuse CO2 and H2S measurements were performed according to the accumulation chamber method, using a non-dispersive infrared (NDIR) LICOR-830 CO2 analyser and ALPHASENSE H2S-BH detectors, respectively. In addition, soil gas samples were collected to analyse the He, H2, O2, N2, CO2, CH4 and CO contents and the isotopic composition of the CO2. Soil CO2 efflux values ranged between non-detectable values and 56.2 g m2 d-1, with an average of 21.7 g m2 d-1. Soil H2S efflux values ranged between non-detectable values and 0.245 g m2 d-1, with an average of 0.027 g m2 d-1. The probability plot technique applied to the soil CO2 efflux data allowed to distinguish three different geochemical populations: background, intermediate and peak represented by 36.9 %, 59.8 % and 3.3 % respectively, with geometric means of 10.8, 25.4 and 50.0 g m2 d-1 respectively. The spatial distribution of soil CO2 efflux data, constructed by means of Sequential Gaussian simulations algorithm, depicted the most important emission anomalies at the western section of the study area. These results can help to identify the possible existence of additional actively degassing geothermal reservoirs to reduce the uncertainty inherent to the selection of the area with the highest potential success in the selection of new exploratory wells at Terceira.

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Problems of Optimum Selection

Perceptual and Motor Skills ◽

10.2466/pms.1968.27.3.715 ◽

1968 ◽

Vol 27 (3) ◽

pp. 715-720

Author(s):

Gail O'Connor

Keyword(s):

Factor Analysis ◽

Multiple Regression ◽

Sources Of Information ◽

Additional Information ◽

Factor Analytic ◽

Optimum Selection ◽

Mechanical Ability ◽

Different Sources ◽

Selection Of ◽

Predictive Efficiency

This study examined the selection of different sources of information made by multiple regression, cutting scores, and factor analytic techniques and investigated these procedures in terms of their comparable predictive efficiency. Prior to their job training, 220 Naval winch operator trainees took a battery of seven McQuarrie subtests for mechanical ability. Criterion scores were derived from ratings given subsequent to training. No differences were found among the three methods. However, it is pointed out that the judicious use of factor analysis can provide additional information about the relationships and complexities of the predictors and criterion not available through multiple regression or cutting scores.

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Stability assessment of slopes with cracks using limit analysis

Canadian Geotechnical Journal ◽

10.1139/cgj-2012-0448 ◽

2013 ◽

Vol 50 (10) ◽

pp. 1011-1021 ◽

Cited By ~ 78

Author(s):

Radoslaw L. Michalowski

Keyword(s):

Limit Analysis ◽

Pore Water Pressure ◽

Water Pressure ◽

Crack Depth ◽

Optimization Procedure ◽

Collapse Mechanism ◽

Open Crack ◽

Stability Assessment ◽

Critical Height ◽

Maximum Crack

Cracks are a common occurrence in soil slopes, and a method is described for including the presence of cracks in stability assessment based on the kinematic approach of limit analysis. While many cracks may be present in a slope, the failure mechanism typically involves one crack, whose location has the most adverse influence on stability. A translational mechanism, typical of rock slope failures, is demonstrated to illustrate the method, followed by a rotation collapse analysis that is more appropriate for soils. Pre-existing (open) cracks are considered, as well as the cracks that form as part of the slope collapse mechanism. The maximum crack depth is determined by stability of the vertical crack boundary. This maximum crack depth may be reduced significantly by seepage forces in the slope. The most adverse location of the crack is determined from an optimization procedure where the minimum of the slope critical height is sought. The presence of water is included in the analysis, and stability charts are developed. The influence of the presence of cracks on stability of gentle slopes was not found to be significant, but the effect on the outcome of the analysis increases with an increase in inclination angle and the presence of pore-water pressure. The difference in the critical height of a 60° slope with an open crack and without one can be as much as 50%.

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Marketing Literature Review

Journal of Marketing ◽

10.1509/jmkg.64.2.109.17997 ◽

2000 ◽

Vol 64 (2) ◽

pp. 109-121

Author(s):

Myron Leonard

Keyword(s):

Literature Review ◽

Database Marketing ◽

Marketing Literature ◽

Additional Information ◽

Ann Arbor ◽

Literature Database ◽

Selection Of

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Selection of Filler Materials to Minimize Preferential Weld Corrosion in Pipeline Steels

10.2118/130513-ms ◽

2010 ◽

Cited By ~ 3

Author(s):

Sudhakar P.V. Mahajanam ◽

Michael W. Joosten

Keyword(s):

Filler Materials ◽

Pipeline Steels ◽

Weld Corrosion ◽

Selection Of

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Welding supports of pins in mobile platforms

Welding Technology Review ◽

10.26628/wtr.v92i4.1111 ◽

2020 ◽

Vol 92 (4) ◽

pp. 25-29

Author(s):

Abilio Silva ◽

Bożena Szczucka-Lasota ◽

Tomasz Węgrzyn ◽

Adam Jurek ◽

Krzysztof Ireneusz Wilczyński

Keyword(s):

Chemical Composition ◽

Heat Affected Zone ◽

High Strength ◽

Welding Parameters ◽

Filler Materials ◽

Mobile Platforms ◽

Varying Thickness ◽

Welding Defects ◽

Movable Platform ◽

Selection Of

The demand for mixed joints of hard-welded steels used in civil engineering and transport is increasing. An example of this can be welding of pins of high-strength steel S690 QL (1.8928) with the arms of a movable platform made of DOCOL 1200M steel from the AHSS group. This joint is difficult to make properly, due to significant differences in the thickness of welded elements and different chemical composition of both steels. The thickness of the cylindrical pin is 40 mm, the diameter of the pin is 50 mm. The thickness of the metal sheet used for the mobile platform arm is 2 mm. . Joints of varying thickness and chemical composition may have cracks in the heat affected zone and in the weld. The purpose of the article is to determine the most appropriate welding parameters and the selection of filler materials that will allow to obtain the correct joint without welding defects.

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CFOSAT wave spectra joining the family of L2P-L3 CMEMS Wave products!

10.5194/egusphere-egu21-7813 ◽

2021 ◽

Author(s):

Annabelle Ollivier ◽

Gerald Dibarboure ◽

Romain Husson ◽

Gael Goimard ◽

Daniele Hauser ◽

...

Keyword(s):

Quality Criteria ◽

New Product ◽

Added Value ◽

Wave Spectra ◽

Additional Information ◽

The Family ◽

Valid Data ◽

Directional Wave ◽

User Friendly ◽

Selection Of

SWIM CFOSAT innovative instrument has already shown its reliability and data quality interest through several publications since its launch in end 2018. Its nadir data are delivered to CMEMS since July 2019 in a L2P/L3. Similarly to other nadir missions AltiKa, Jason3, HY2B, S3&#8230;,&#160; these easy to use products are based on a selection of valid data from quality criteria, and bias alignment to buoys networks. They are provided in near real time (3h) and with a 1Hz sampling.In 2021, the CFOSAT project team is happy to provide to CMEMS, in addition to the mission full products, a &#160;user friendly product, with preselected valid datasets of directional wave spectra and related parameters, and additional information directly derived from the calval expertises upstream. Thanks to it, non expert users should be able to have a simple access to this new product and easy compare it to SAR Wavemode L3 products already in the CMEMS catalogue.This presentation is a user friendly approach to describe the added value, the future improvements planned and the potential of such product for non experts applications.

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