scholarly journals Evaluation of Ferromagnetic Steel Hardness Based on an Analysis of the Barkhausen Noise Number of Events

Materials ◽  
2020 ◽  
Vol 13 (9) ◽  
pp. 2059 ◽  
Author(s):  
Maciej Roskosz ◽  
Krzysztof Fryczowski ◽  
Krzysztof Schabowicz
Keyword(s):  
Strain Hardening ◽  
Characteristic Property ◽  
Thermochemical Treatment ◽  
Diagnostic Information ◽  
Barkhausen Noise ◽  
Signal Characteristic ◽  
Determination Coefficient ◽  
Ferromagnetic Steel

Measurements are carried out of the Barkhausen noise (BN) and hardness on specimens where changes in hardness were obtained due to strain hardening (S235 and DC01 steels) and due to thermochemical treatment (AMS 6414 steel). A method is presented of processing the recorded BN signal to extract diagnostic information. The BN number of events is selected as the signal characteristic property to develop relevant correlations. A new methodology is presented for the development of correlations between the Barkhausen noise number of events and hardness. A possibility is indicated of developing correlations with a high R2 determination coefficient. The method limitations are specified.

scholarly journals Method of Determining the Strain Hardening of Carburized Elements in Ansys Environment

2015 ◽  
Vol 240 ◽  
pp. 74-80 ◽  
Author(s):  
Sebastian Lipa ◽  
Jacek Sawicki ◽  
Emilia Wołowiec Korecka ◽  
Konrad Dybowski ◽  
Piotr Kula
Keyword(s):  
Surface Layer ◽  
Carbon Content ◽  
Strain Hardening ◽  
Material Properties ◽  
Computational Algorithm ◽  
Thermochemical Treatment ◽  
Computation Time ◽  
Fem Analysis ◽  
Two Factors ◽  
Carburizing Process

The paper presents a method based on FEM analysis of determining the strain hardening of elements after the thermochemical treatment. A computational algorithm, which takes into account two factors, has been suggested. Firstly, the gradient of material properties resulting from the changes in the carbon content in the surface layer after the carburizing process. Secondly, the phase transformations occurring during the hardening of the material. The proposed flowchart did not include the flow effect, which greatly reduced the computation time by eliminating tedious CFD calculations. Thanks to an original program Converter coupled with a commercial software's SimHard, SimCarb J Math Pro and Ansys the carburizing process followed by quenching in gases was modeled. In parallel to the numerical calculations the results were verified experimentally. The results of FEM analysis for the tube made of stainless EN 16CrMn5 subjected to three processes of thermochemical treatment have also been presented in the paper. The experimental results were compared with the numerical simulations and a satisfactory convergence has been achieved.

scholarly journals Dependence of Coercivity and Barkhausen Noise Signal on Martensitic Stainless Steel with and without Quench

2020 ◽  
Author(s):  
Hiroaki Kikuchi ◽  
Kohei Sugai ◽  
Takeshi Murakami ◽  
Keiichi Matsumura
Keyword(s):  
Mechanical Property ◽  
Residual Stress ◽  
Stainless Steel ◽  
Nondestructive Evaluation ◽  
Martensitic Stainless Steel ◽  
Noise Signal ◽  
Barkhausen Noise ◽  
Magnetic Parameters ◽  
Property Changes ◽  
Ferromagnetic Steel

We evaluated hysteresis curves and Barkhausen noise properties of the martensitic stainless steel with and without quench, and then investigated the relations between magnetic parameters and hardness based on microstructure changes. The quench introduced to reduce grain size, which relates to an increment of coercivity and Vickers hardness, a decrease in Barkhausen signal. The magnetic property changes reflect the changes in microstructures and mechanical property appeared on the quenched specimen. The obtained results contribute to aim to develop a magnetic nondestructive evaluation of residual stress appeared on the ferromagnetic steel combined with and without quench.

Parents' Perception of Diagnostic Reports and Conferences

1983 ◽  
Vol 14 (2) ◽  
pp. 114-120 ◽  
Author(s):  
Betty U. Watson ◽  
Ronald W. Thompson
Keyword(s):  
Medical Treatment ◽  
Diagnostic Information ◽  
Learning Language ◽  
Speech Learning ◽  
Hearing Problems

The purpose of this study was to evaluate parents' reactions and understanding of diagnostic information from written reports and conferences in a clinic which provides multidisciplinary evaluations for children with speech, learning, language, and hearing problems. Previous studies and anecdotal reports suggested that many parents do not receive appropriate diagnostic information about their children. In the present study questionnaires were mailed to parents who had received reports of evaluations and most of whom had attended hour-long conferences covering the findings. Questionnaires were also sent to professionals who had received reports. Fifty-seven percent of the parents, and 63% of the professionals returned the questionnaires. Ninety percent of the parents indicated that they had understood the results as they were presented in the conference. Ninety-three percent of the professionals and 89% of the parents stated they understood the conclusions of the written reports .Further, 83% of the parents and 80% of the professionals reported that the findings had made a change in the child's educational or medical treatment. The percentage of parents who reported understanding the findings was greater than expected. The specific informing techniques used in this study are discussed.

An Introductory Examination of Speech Disfluencies in Spanish–English Bilingual Children Who Do and Do Not Stutter During Narratives

2020 ◽  
Vol 5 (1) ◽  
pp. 131-141
Author(s):  
Cristina Rincon ◽  
Kia Noelle Johnson ◽  
Courtney Byrd
Keyword(s):  
Diagnostic Criteria ◽  
Preliminary Data ◽  
Diagnostic Information ◽  
English Speakers ◽  
Bilingual Children ◽  
English Bilingual ◽  
Developmental Stuttering ◽  
Mean Length Of Utterance

Purpose The purpose of this study is to examine the frequency and type of speech disfluencies (stuttering-like and nonstuttering-like) in bilingual Spanish–English (SE) children who stutter (CWS) to SE children who do not stutter (CWNS) during narrative samples elicited in Spanish and English to provide further diagnostic information for this population and preliminary data toward an expansion of this study. Method Participants included six bilingual SE children (three CWS, three CWNS) ranging in age from 5 years to 7;5 (years;months) and recruited from the surrounding Houston, Texas area. Participants provided a narrative sample in English and Spanish. The frequency of speech disfluencies was tabulated, and mean length of utterance was measured for each sample. Results Results indicate that both talker groups exceed the diagnostic criteria typically used for developmental stuttering. Regardless of the language being spoken, CWS participants had a frequency of stuttering-like speech disfluencies that met or exceeded the diagnostic criteria for developmental stuttering that is based on monolingual English speakers. The CWNS participants varied in meeting the criteria depending on the language being spoken, with one of the three CWNS exceeding the criteria in both languages and one exceeding the criteria for percentage of stuttering-like speech disfluencies in one language. Conclusion Findings from this study contribute to the development of more appropriate diagnostic criteria for bilingual SE-speaking children to aid in the reduction of misdiagnoses of stuttering in this population.

On Permissible Attribute Classes in Noncompensatory Cognitive Diagnosis Models

Methodology ◽  
2014 ◽  
Vol 10 (3) ◽  
pp. 100-107 ◽  
Author(s):  
Jürgen Groß ◽  
Ann Cathrice George
Keyword(s):  
Diagnostic Information ◽  
Cognitive Diagnosis ◽  
Latent Classes ◽  
Psychometric Test ◽  
Cognitive Diagnosis Models ◽  
Dina Model

When a psychometric test has been completed by a number of examinees, an afterward analysis of required skills or attributes may improve the extraction of diagnostic information. Relying upon the retrospectively specified item-by-attribute matrix, such an investigation may be carried out by classifying examinees into latent classes, consisting of subsets of required attributes. Specifically, various cognitive diagnosis models may be applied to serve this purpose. In this article it is shown that the permission of all possible attribute combinations as latent classes can have an undesired effect in the classification process, and it is demonstrated how an appropriate elimination of specific classes may improve the classification results. As an easy example, the popular deterministic input, noisy “and” gate (DINA) model is applied to Tatsuoka’s famous fraction subtraction data, and results are compared to current discussions in the literature.

Reduction in size of digital images: does it lead to less detectability or loss of diagnostic information?

1998 ◽  
Vol 27 (2) ◽  
pp. 93-96 ◽  
Author(s):  
C H Versteeg ◽  
G C H Sanderink ◽  
S R Lobach ◽  
P F van der Stelt
Keyword(s):  
Digital Images ◽  
Diagnostic Information
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