Characterization of the fracture behaviour of X42 microalloyed pipeline steel

Purpose – The purpose of this paper is to investigate the fracture of grade X42 microalloyed steel used as pipe material after tensile test at room temperature and impact tests at 0, −20 and −40°C, respectively. Design/methodology/approach – In the first stage of the study, X42 steels in the form of sheet and pipe materials were selected and etched samples were characterized using light microscope. In the second stage, mechanical properties of steels were obtained by microhardness measurements, static tensile and impact tests and all the broken surfaces were examined by scanning electron microscope to determine the fracture type as a function of both microstructure and loading. Findings – The examinations revealed that: first, the sheet material had a typical ferritic-pearlitic matrix, second, the transverse section of the sheet steel exhibited a matrix consisting of polygonal ferrite-aligned pearlite colonies and the longitudinal one had elongated ferrite phase and pearlite colonies in the direction of rolling, third, ferrite and pearlite distribution was different from the sheet material due to multiaxial deformation in the pipe material, fourth, tensile fracture surfaces of the steels had typical dimple fracture induced by microvoid coalescence, fifth, impact fracture surfaces of the steels changed as a function of the test temperature and cleavage fracture mode of ferritic-pearlitic matrix became more dominant as the temperature decreased, and sixth, grain morphology had an effect on the fracture behavior of the steels. Originality/value – The paper explains the fracture behaviour of X42 microalloyed pipeline steel and its fractographical analysis.

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Effect of material thickness and reduction ratio on roughness transfer in skin-pass rolling to DC04 grade sheet materials

Industrial Lubrication and Tribology ◽

10.1108/ilt-10-2020-0377 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Batuhan Özakın ◽

Bilal Çolak ◽

Naci Kurgan

Keyword(s):

Sheet Material ◽

Sheet Steel ◽

Rolling Process ◽

Reduction Ratio ◽

Thickness Change ◽

Content Type ◽

Material Thickness ◽

Skin Pass ◽

Sheet Materials ◽

Thickness Sheet

Purpose The last stage of the cold rolling process is skin-pass rolling and one of its most significant goals is to obtain appropriate topography on the surface of the sheet steel used extensively such as in automotive industry. The purpose of this paper is to investigate the effect of thickness change and various reduction ratios on roughness transfer of DC04 grade sheet material. Design/methodology/approach DC04 grade sheet materials with different reduction ratios and several thicknesses were subjected to skin-pass rolling process in the rolling equipment with a two-high roll. Some roughness parameters were determined as a result of roughness measurements from the surfaces of roughened sheet materials. Findings While the roughness transfer is higher in 1-mm thick material in reduction ratios up to 430 micrometers; in reduction ratios above 430 micrometers, it is higher for 1.5-mm thick materials. As the reduction ratio increases in DC04 grade sheet materials, the homogeneity of the roughness distribution in 1-mm thickness sheet material deteriorates, while the roughness distribution in 1.5-mm thickness sheet material is more homogeneous. Originality/value This paper demonstrates how material thickness and reduction ratio affect the roughness transfer in skin-pass rolling. The results obtained can be used by optimizing in manufacturing processes.

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A fractal model of tensile fracture surfaces for particulate‐filled polymer composites

Journal of Applied Polymer Science ◽

10.1002/app.28448 ◽

2008 ◽

Vol 109 (6) ◽

pp. 3763-3767 ◽

Cited By ~ 3

Author(s):

J. Z. Liang ◽

C. B. Wu

Keyword(s):

Polymer Composites ◽

Fractal Model ◽

Tensile Fracture ◽

Filled Polymer ◽

Fracture Surfaces

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Mechanical and Fractographical Characterization of Extruded Al-Mg-Si-Zr Alloys

MATEC Web of Conferences ◽

10.1051/matecconf/201818802017 ◽

2018 ◽

Vol 188 ◽

pp. 02017

Author(s):

Fulya Kahrıman ◽

Muzaffer Zeren

Keyword(s):

Fracture Behavior ◽

Direct Chill ◽

Grain Structure ◽

Tensile Fracture ◽

Casting Method ◽

Cross Sectional ◽

Fracture Surfaces ◽

The Matrix ◽

Zr Alloys

In this study, the chemical composition of Al-0.8Mg-0.8Si alloys was modified with the addition of 0.1 and 0.2 wt.-% Zr. The billets were manufactured by direct chill casting method, homogenized at 560 °C for 6h and then extruded in order to obtain profiles having hollow and circular sections. Recrystallization layer (shell) became narrower due to the addition of Zr. This was attributed to the formation of very fine precipitates (Al3Zr) within the matrix. The mechanical properties showed that both yield and tensile strengths increased as a function of Zr content. Tensile fracture surfaces were examined by scanning electron microscope and the fractographs reflected the effect of grain structure on the fracture behavior of studied alloys. All fracture surfaces indicated typical dimple ruptures, however, the size of dimples were observed as finer structures as a function of Zr content. As seen in cross-sectional graphs, as the Zr content increased the grain structure was refined due to Al3Zr precipitates. These fine precipitates caused the formation of fine and shallow dimples under loading.

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Dynamic tensile process of blended fabric using finite element method

International Journal of Clothing Science and Technology ◽

10.1108/ijcst-09-2019-0133 ◽

2020 ◽

Vol 32 (5) ◽

pp. 707-724

Author(s):

Xuzhong Su ◽

Xinjin Liu

Keyword(s):

Finite Element Method ◽

Finite Element ◽

Experimental Testing ◽

Woven Fabrics ◽

Weft Yarn ◽

Tensile Fracture ◽

Content Type ◽

Tensile Process ◽

Simulation Results ◽

Element Method

PurposeTensile property is one basic mechanics performance of the fabric. In general, not only the tensile values of the fabric are needed, but also the dynamic changing process under the tension is also needed. However, the dynamic tensile process cannot be included in the common testing methods by using the instruments after fabric weaving.Design/methodology/approachBy choosing the weft yarn and warp yarn in the fabric as the minimum modeling unit, 1:1 finite element model of the whole woven fabrics was built by using AutoCAD software according to the measured geometric parameters of the fabrics and mechanical parameters of yarns. Then, the fabric dynamic tensile process was simulated by using the ANSYS software. The stress–strain curve along the warp direction and shrinkage rate curve along the weft direction of the fabrics were simulated. Meanwhile, simulation results were verified by comparing to the testing results.FindingsIt is shown that there are four stages during the fabric tensile fracture process along the warp direction under the tension. The first stage is fabric elastic deformation. The second stage is fabric yield deformation, and the change rate of stress begins to slow down. The third stage is fiber breaking, and the change of stress fluctuates since the breaking time of the fibers is different. The fourth stage is fabric breaking.Originality/valueIn this paper, the dynamic tensile process of blended woven fabrics was studied by using finite element method. Although there are differences between the simulation results and experimental testing results, the overall tendency of simulation results is the same as the experimental testing results.

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Tensile response and fracturing process in moderate- and high-plasticity clays

Canadian Geotechnical Journal ◽

10.1139/cgj-2019-0082 ◽

2020 ◽

pp. 1-11

Author(s):

Giulia Forlati ◽

Paul Shepley

Keyword(s):

Moisture Content ◽

Fracture Behaviour ◽

Soil Layer ◽

Clay Soils ◽

Tensile Fracture ◽

Future Research ◽

High Plasticity ◽

Bending Tests ◽

Fracturing Process ◽

The Difference

Sinkholes in clay soils can be considered as the collapse of a soil layer previously bridging a void. Here, flexural deformation in the clay drives the formation of tensile cracks from the lowest surface of the layer and the consequent soil collapse is from crack propagation. Considering a simplified model of the sinkhole geometry, this paper aims to describe the tensile and fracture behaviour of clay soils with different plasticity indices. Speswhite kaolin, London, and Durham clays were tested using direct tensile and bending tests. Moderate- and high-plasticity clays showed a nonlinear fracture response with increasing moisture content, while low-plasticity clays demonstrated a linear response. Bending tests confirmed the importance of the moisture content while the plasticity index confirmed the difference in ductile or fragile collapse for fracture propagation. To assess the results, elasto-plastic fracture mechanics (EPFM) theory was applied to clays with appropriate modifications. The analysis demonstrated that EPFM theory provides a good baseline for predicting tensile fracture behaviour in clay soils, which can be extended in future research.

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Simulation and experimental studies of induction hardening behavior of a new medium-carbon, low-alloy wear resistance steel

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-06-2019-0227 ◽

2019 ◽

Vol 39 (1) ◽

pp. 158-165

Author(s):

Vahid Javaheri ◽

John Inge Asperheim ◽

Bjørnar Grande ◽

Satish Kolli ◽

David Porter

Keyword(s):

Experimental Studies ◽

Induction Hardening ◽

Transformation Model ◽

Pipe Material ◽

Commercial Software ◽

Content Type ◽

Hardening Behavior ◽

Heating And Cooling ◽

History Of ◽

Slurry Transport

Purpose The purpose of this work is to determine the induction hardening behavior of a new steel composition. For this purpose, Flux2D commercial software together with a Gleeble thermomechanical simulator has been used to numerically and physically simulate the material properties profile of an induction hardened slurry transportation pipe made of a recently developed 0.4 Wt.% C, Nb-microalloyed steel. Design/methodology/approach Flux 2D commercial software together with a Gleeble thermomechanical simulator machine has been used to predict the induction behavior of the studied material. After calculating the thermal history of a 400 mm diameter, 10 mm thick pipe at various positions through the thickness, different heating and cooling paths were physically simulated using the Gleeble machine to predict the through thickness material microstructure and hardness profiles. Finding The results showed that by coupling a phase transformation model considering the effect of heating rate on the austenite transformation temperatures which allows calculations for arbitrary cooling paths with calculated induction heating and quenching thermal cycles, it has been possible to design induction hardening parameters for a slurry transport pipe material. Originality/value The composition used in this research as well as the methodology approach is designed at this work.

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Evaluation of Tensile Fracture Behaviour of CFRP under Varied Strain Rate with High-Speed Imaging and DIC

Journal of the Japan Society for Composite Materials ◽

10.6089/jscm.40.153 ◽

2014 ◽

Vol 40 (4) ◽

pp. 153-159 ◽

Cited By ~ 1

Author(s):

Yoshiyasu HIRANO ◽

Hideaki KUSANO ◽

Yuichiro AOKI

Keyword(s):

Strain Rate ◽

High Speed ◽

Fracture Behaviour ◽

Tensile Fracture ◽

High Speed Imaging

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The synergistic inhibition effect between imidazoline and the oxide film on L360 steel in CO2/H2S systems

Anti-Corrosion Methods and Materials ◽

10.1108/acmm-01-2015-1490 ◽

2015 ◽

Vol 62 (3) ◽

pp. 143-148 ◽

Cited By ~ 2

Author(s):

Guohao Chen ◽

Lingyun Li ◽

Jian Ouyang ◽

Zhuoyan Zhu ◽

Feng Wang ◽

...

Keyword(s):

Oxide Film ◽

Electrochemical Impedance ◽

Pipeline Steel ◽

X Ray Diffraction ◽

Gas Field ◽

Content Type ◽

Inhibition Effect ◽

Synergistic Inhibition ◽

Inhibition Performance ◽

Synergistic Inhibition Effect

Purpose – The aim of the present paper was to investigate the inhibition performance of the OF and/or IM on L360 steel in CO2/H2S environments. The pipeline steel surface usually has been pre-treated before using in the oil/gas field, such as by passivation, blackening, and phosphiding. The effectiveness of inhibition can vary because there are many differences between the metal matrix and the treated film. Design/methodology/approach – Imidazoline (IM) was synthesized by using oleic acid and diethylenetriamine, and its composition was verified using Fourier transform infrared spectroscopy. The oxide film (OF) covering a sample of L360 steel was characterized using X-ray diffraction, and its surface morphology was observed using scanning electron microscope. Electrochemical impedance spectroscopy measurements were conducted to study the inhibition performance of IM- and/or OF-covered L360 steel in the CO2/H2S environments. Findings – The results show that IM and OF can prevent corrosion on L360 steel in CO2/H2S environments, and the synergistic inhibition effect of IM and OF was very evident. A possible model is proposed to explain the synergistic inhibition effect in the CO2/H2S environments of IM and OF on L360 steel. Originality/value – Few reports have concerned the effect of the OF on the inhibitor’s performance, especially in CO2/H2S systems. The aim of the present study was to investigate the inhibition performance of the OF and/or IM on L360 steel in CO2/H2S environments. A model is proposed to explain the synergistic inhibition effect mechanism between IM and OF.

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