Wyniki wyszukiwania - Biblioteka Nauki

1

Badanie właściwości mechanicznych stali S355JR o różnych typach budowy mikrostruktury

100%

Lipiec S.

Stal, Metale & Nowe Technologie

|

2023

|

tom nr 1-2

36--40

PL

W artykule analizowana jest stal S355JR o różnych typach budowy mikrostruktury: poddana normalizacji, ze strukturą ferrytyczno-perlityczną (FP), oraz po wygrzewaniu austenityzującym, następnie chłodzona z dużą prędkością poprzez hartowanie w oleju, ze strukturą ferrytyczno-bainityczną (FB).

XX

An important aspect in the engineering design process is to know the true material characteristics of steels used in specific microstructures. These steels, depending on, among other things, heat treatment or working conditions and regimes, are characterised by a different microstructure. It is important to know the levels of both strength, ductility and fracture toughness of steels with different microstructure. This paper presents the results of an experimental study of S355JR steel with two types of microstructure: ferritic-perlitic and ferritic-bainitic. The basic strength and ductility characteristics of the steel determined by uniaxial tensile test and the results of fracture toughness tests are presented.

2

Badanie właściwości mechanicznych stali S355JR o różnych typach budowy mikrostruktury

100%

Lipiec S.

|

tom nr 1

16--20

PL

W artykule analizowana jest stal S355JR o różnych typach budowy mikrostruktury: poddana normalizacji, ze strukturą ferrytyczno-perlityczną (FP), oraz po wygrzewaniu austenityzującym, następnie chłodzona z dużą prędkością poprzez hartowanie w oleju, ze strukturą ferrytyczno-bainityczną (FB).

3

Stress distribution in front of the crack – analytical solutions vs. numerical. Can the differences be minimized?

63%

Neimitz A. , Lipiec S.

Journal of Theoretical and Applied Mechanics

|

2019

|

tom Vol. 57 nr 3

713--721

EN

It is shown that it is possible to obtain such parameters as α and Q, which, when used in the analytical formulae proposed by O’Dowd and Shih, can lead to stress distributions similar to those obtained numerically. The numerical solution obtained after calibration of the stress-strain uniaxial curve and assuming large strains is expected to be close to the “real” stress distribution. Thus, the analytical solution after correction is also close to the “real” stress distribution. These new values of α and Q can now be used in fracture criteria proposed within the scope of classical nonlinear fracture mechanics.

4

Wpływ kształtu karbu na rozkłady naprężeń i charakter zniszczenia próbek ze stali S235

45%

Dzioba I. , Lipiec S. , Świt G. , Adamczak-Bugno A. , Krampikowska A.

Energetyka

|

2023

|

tom nr 11

642--643

PL

W artykule podjęto próbę oceny wpływu kształtu karbu na rozkłady naprężeń oraz charakter zniszczenia próbek ze stali pobranej z infrastruktury gazociągu (stal S235). Analizy oparto na wynikach różnych podejść badawczych: wynikach badań laboratoryjnych z rejestracją sygnałów emisji akustycznej (AE) oraz rezultatów symulacji numerycznych z wykorzystaniem metody elementów skończonych. Pozwoliło to na określenie charakteru rozwoju naprężeń w próbkach wraz z przyłożonym obciążeniem oraz wyznaczenie wartości krytycznych w momencie zniszczenia. Dane te mogą być wykorzystane do definicji kryterium zniszczenia analizowanej stali.

EN

This study attempts to assess the influence of notch shape on the stress distributions and failure character of steel specimens taken from the gas pipeline infrastructure (S235 steel). The analyses were based on the results of different research approaches: the results of laboratory tests with recording of acoustic emission (AE) signals and the results of numerical simulations using the finite element method. This made it possible to determine the nature of the stress development in the specimens with the applied load and to determine the critical values at failure. These data can be used to define the failure criterion of the steel analysed.

5

Innovative acoustic emission method for monitoring the quality and integrity of ferritic steel gas pipelines

38%

Świt G. , Ulewicz M. , Pała R. , Adamczak-Bugno A. , Lipiec S. , Krampikowska A. , Dzioba I.

Production Engineering Archives

|

2024

|

tom Vol. 30, Iss. 2

233--240

EN

This article presents a comprehensive improvement in the experimental analysis of cracking processes in smooth and sharp V-notched samples taken from gas transport pipelines, utilizing the acoustic emission (AE) method. The research aimed to establish a robust correlation between the failure mechanisms of uniaxially tensile samples and the distinct characteristics of AE signals for enhanced quality management in pipeline integrity. The study encompassed materials from two different straight pipe sections, encompassing both long-term used materials and new, unused materials. Through the application of the k-means grouping method to AE signal analysis, we achieved the identification of AE signal parameters characteristic of various stages of the material destruction process. This advancement introduces a significant improvement in monitoring and managing the operational safety of pipeline networks, offering a methodology that leverages advanced acoustic emission signal analysis. The outcomes present significant implications for the pipeline industry by proposing methods to enhance safety systems and more effectively manage the integrity and quality of gas infrastructure.

6

Experimental-numerical analysis of the fracture process in smooth and notched V specimens

38%

Świt G. , Dzioba I. , Ulewicz M. , Lipiec S. , Adamczak-Bugno A. , Krampikowska A.

Production Engineering Archives

|

2023

|

tom Vol. 29, Iss. 4

444-451

EN

This paper presents the outcomes of quality tests conducted on specimens, both smooth and V-notched, subjected to uniaxial tension, which were extracted from a gas transport pipeline. The introduction of the V-notch introduced variations in the stress and strain component fields near the plane of maximum constriction, consequently leading to their failure through different mechanisms. The process included the implementation of quality management practices such as numerical modeling and simulation of the loading of the specimens using ABAQUS. The material model employed in these calculations was defined and verified to ensure quality control. Subsequent to the numerical calculations, maps of the stress and strain component fields were generated, contributing to the quality assessment of the specimens. It was determined that the quality management process for the smooth specimen identifies the initiation of failure primarily due to the normal stress component in the central region of the plane with the largest constriction. In contrast, in the V-notched specimen, quality management efforts revealed that failure initiation occurs due to the tangential stress component, and failure proceeds through the shear mechanism. These results are valuable in developing a quality-driven methodology for monitoring the operational safety of gas network pipelines, primarily based on the analysis of acoustic emission signals.