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Properties of WC-Co coatings with Al2O3 addition

Radek Norbert

Production Engineering Archives

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2023

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Vol. 29, Iss. 1

94--100

EN

Properties of WC-Co coatings with Al2O3 addition on the C45 mild steel surface in acidic chloride solution were examined. The WC-Co-Al2O3 coatings on steel surfaces were deposited by an electro-spark (ESD) technique. The anti-corrosion properties of the coatings were mainly investigated by electrochemical methods. Moreover, the scanning electron microscope (SEM) was employed for the observation of the surface of materials. The structure of coatings depended on the composition of electrospark electrodes. In the WC80-Co5-Al2O315 coating, the largest corrosion resistance was shown. The corrosion rate of the specimen was approximately eight times smaller than the coating with out of Al2O3 addition. The aim of the research was to obtain, by adding alumina, an improvement in the functional properties of WC-Co coatings produced by the ESD method. Due to the original features of ESD coatings, they can be used in sliding friction pairs and as anti-wear coatings on cutting tools. C-Co coatings with AlO3 addition.

2

Carbon Fibre Reinforced Polymer Fatigue Strengthening of Old Steel Material

Kowal Maciej, Pietras Daniel

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 1

197--209

EN

This paper reports the experimental results of a study investigating the effect of CFRP strengthening of metallic structures for increasing fatigue life. In the study, samples made form puddled steel and mild S235 grade steel strengthened with CFRP strips were examined. Samples were subjected to tensile fatigue loading with a stress ratio R of 0.115 and 0.130 (mild steel samples) and 0.13/1.25/0.15/1.07 (puddled steel samples). A total of 9 samples with CFRP/steel single overlap joints and 20 reference specimens were tested to determine their fatigue life and failure modes. Normal modulus CFRP strips with one cross section (20 x 1.4 mm) were used in this study. Laboratory test results showed that CFRP strengthening has visible effect on the fatigue life of the steel. The application of adhesively bonded CFRP laminates significantly prolongs fatigue life of the specimens. The increase in fatigue life of the steel samples strengthened with CFRP strips was 2 to 16 times (for mild steel) and 11.6 to 34.8 times (for puddled steel).

3

Corrosion tests of metal pipes in drinking water systems using electrochemical methods

Adetunji Olayide R., Oyelowo Mojisola A., Adekunle Nurudeen O., Adeogun Abideen I., Okediran Iliyas.K

Ochrona przed Korozją

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2022

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nr 2

43--49

EN

Metals constitute some of the major materials for making water delivery pipelines. However, the service life of metallic pipelines is affected by corrosion. Mild Steel (MS), Galvanized Steel (GS) and Copper were selected based on their strength and corrosion resistance. They were subjected to Potentiodynamic Polarization (PP) and Electrochemical Impedance Spectroscopy (EIS) investigations using water as the electrolyte from selected sampling points (A, B, C, D and E) on the University of Lagos, Akoka water distribution network. Corrosion current density (Icorr) and Impedance (Z) were measured in A/mm2 and ohms respectively. The morphology of the corroded samples was examined using Scanning Electron Microscope (SEM). The result obtained from PP investigation showed Icorr in the low range for the three metals considered. Similarly, for EIS, Z values measured were high for MS, GS and Cu. Both methods indicated that Cu was the most corrosion resistant material, closely followed by GS and lastly MS. The SEM images clearly showed that among the three specimens, the morphology of Cu remained unaffected by the environment. On the other hand, MS and GS showed evidences of corrosion with pits. The large amounts of iron established in the studied water distribution system, confirmed corrosion of water pipes.

PL

Metale są jednym z głównych materiałów konstrukcyjnych wodociągów. Jednak trwałość metalowych rurociągów jest ograniczona ze względu na korozję. Ze względu na wytrzymałość i odporność na korozję do budowy rurociągów stosuje się stal miękką (MS), stal ocynkowaną (GS) i miedź. Próbki pobrane w wybranych miejscach (A, B, C, D i E) sieci wodociągowej Akoka poddano na Uniwersytecie w Lagos badaniom metodą polaryzacji potencjodynamicznej (PP) i elektrochemicznej spektroskopii impedancyjnej (EIS) z zastosowaniem wody jako elektrolitu. Gęstość prądu korozyjnego (Icorr) i impedancję (Z) zmierzono odpowiednio w A/mm2 i omach. Morfologię skorodowanych próbek zbadano za pomocą skaningowego mikroskopu elektronowego (SEM). Wynik otrzymany w badaniach PP wykazał Icorr w niskim zakresie dla trzech rozważanych metali. Podobnie w przypadku EIS zmierzone wartości Z były wysokie dla MS, GS i Cu. Obie metody wskazywały, że miedź jest najbardziej odpornym na korozję materiałem, a następnie ocynkowana stal o podobnych właściwościach i na końcu stal miękka. Na mikrofotografiach SEM wyraźnie widać, że spośród trzech próbek metali środowisko nie miało wpływu na morfologię Cu. MS i GS wykazały ślady korozji z wżerami. Duże ilości żelaza stwierdzone w badanym systemie wodociągowym potwierdziły korozję rur.

4

Analysis of the influence of the blanking clearance size to the burr development on the sheet of mild steel, brass and aluminium in blanking process

Kamarul Adnan A. A., Azinee S. N., Norsilawati N., Izzul K. A. M.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 111, nr 1

26--32

EN

Purpose: This research aims to analyse the influence of blanking clearance size on the burr development for mild steel sheet, brass and aluminium. The main reason for this research is estimating the burr size on blank parts. It is still significant since the quality of the products is determined by evaluating the amount of allowable burr in the parts. Design/methodology/approach: For the blanking process on the 3.00 mm thick sheets, various sizes of blanking clearance for a 20 mm diameter of the die opening are employed, as is the technique for obtaining the parts. Then the height of the burr on each product was measured using a micrometre and toolmaker microscope. The height of burr for each size of blanking clearance have been recorded and compared using a graph. Comparison made to identify which measure of blanking clearance and which type of material will produce a small size of burr. Findings: For mild steel, brass, and aluminium, blanking clearance 0.15 mm produced burr heights of 0.088 mm, 0.015 mm, and 0.024 mm, and blanking clearance 0.13 mm produced bur heights of 0.192 mm, 0.055 mm, and 0.046 mm, respectively. The brass had a lower burr height than mild steel and aluminium, according to the results. More significant blanking clearance (0.15 mm) produced a smaller size of burr compared to a smaller blanking clearance (0.13 mm). Practical implications: This study focuses on burr height rather than the wear of the punch and die cutting edge; burr height can affect punch and die sharpness. It also can guide practitioners in estimating blanking clearance and the burr height of mild steel, brass and aluminium. Originality/value: This paper demonstrates that the gap between the punch and die influences the burr height. The material strength also affects the burr height, with a high tensile strength resulting in a larger burr.

5

Effect of Friction Machining on Low Carbon Steel with Titanium Traces in terms of Surface Hardening

Sheikh Ali R.

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 4

41--46

EN

This work is an experimental study of thermo-mechanical surface hardening of mild steel with trace elements like titanium in negligible concentrations. This is somewhat an advanced technique used to harden steel surface which can be hardened in many typical ways. The concept is combining the thermal as well as mechanical technique to attain better results. It is quite obvious that mechanical refers to the compressive loading during machining and thermal refers to producing heat on the surface of work piece. The ideal conditions are when the heat produced is enough to achieve austenite and then subsequent quick cooling helps in the formation of marten site, which is metallurgically the most highly strong phase of steel, in terms of hardness. The coolant used preferably is the emulsified oil which flows on the surface during machining with variable rate of flow as the optimum effect is. This process hardens the surface of steel and increases its resistance against wear and abrasion. Preference is to achieve surface hardening using the conventional equipment so that operational cost is kept low and better results are attained. This technique has been quite successful in the laboratory. It can be termed as friction hardening. Some improvements in the process scheme and working environment can be made to get better results.

6

Experimental study of mild steel cutting process by using the plasma arc method

Magid H.M.

Journal of Achievements in Materials and Manufacturing Engineering

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2021

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Vol. 108, nr 2

75--85

EN

Purpose: In this study, plasma arc cutting (PAC) is an industrial process widely used for cutting various away types of metals in several operating conditions. Design/methodology/approach: It is carried out a systematic or an authoritative inquiry to discover and examine the fact, the plasma cutting process is to establish the accuracy and the quality of the cut in this current paper assessed a good away to better the cutting process. Findings: It found that the effect of parameters on the cutting quality than on the results performed to accomplish by statistical analysis. Research limitations/implications: The objective of the present work paper is to achieve cutting parameters, thus the quality of the cutting process depends upon the plasma gas pressure, scanning speed, cutting power, and cutting height. Practical implications: The product of the plasma cutting process experimentally has been the quality of the cutting equipment that was installed to monitor kerf width quality by exam the edge roughness, kerf width, and the size of the heat-affected zone (HAZ). Originality/value: The results reveal that were technically possessed of including all the relevant characteristics, then a quality control for the cutting and describe the consequence of the process parameters.

7

Stale konstrukcyjne historycznych mostów spawanych

Hołowaty J.

Przegląd Spawalnictwa

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2018

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R. 90, nr 5

99--102

PL

Przedstawiono stale konstrukcyjne, które znajdowały zastosowanie w budowie pierwszych mostów spawanych. Właściwości stali zlewnych i wczesnych stali o podwyższonej wytrzymałości powodowały, że nie wszystkie z nich nadawały się do konstrukcji spawanych. Rozwój historycznych stali spawalnych w konstrukcjach mostowych przedstawiono na podstawie przeglądu norm i zaleceń projektowych. Rozpoznanie tych stali w istniejących mostach jest bardzo istotne pod względem planowanego zakresu modernizacji i wzmocnień oraz możliwości stosowania spawania.

EN

The structural steels which were used in construction of the first welded bridges are presented. Properties of mild steels and early high strength steels caused that not all of them were suitable for welded structures. The development of historic weldable steels in bridge structures is reviewed over codes and design requirements. Recognition of these steels in existing bridges is very essential to plan a retrofitting and strengthening range as well as possibility of using welding.

8

Sustainable use of Natural Resources as Alternative for the Hazardous Corrosion Inhibitor of Mild Steel/Dilute Sulfuric Acid Interface: Weight Loss, EIS, AFM and FTIR Studies

Tezeghdenti M., Etteyeb N., Dhouibi L., Kanoun O.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 2

697--707

EN

Point of present exploration was to figure out the anticorrosion activity of Acacia Cyanophylla (Saligna leaves) extract on the corrosion of mild steel in dilute sulfuric acid medium, using weight loss measurements and electrochemical impedance spectroscopy. The result of the study revealed that the extract act as a potent inhibitor on mild steel in acid medium. The increase in inhibitor concentration and immersion time showed a positive effect on inhibition efficiency. EIS exhibited one capacitive loop which indicates that the corrosion reaction is controlled by charge transfer process. The increase of phase shift (n) in presence of (ACLE) lower surface roughness. This change reveals the adsorption of the inhibitor compound on the steel surface. According to the results of weight loss measurements, the adsorption of the extract on the steel surface can be described by the Langmuir isotherm. The inhibition mechanism of (ACLE) molecules involves physical interaction between the inhibitor and metal surface. Additionally, Protective film formation against acid attack was confirmed by FT-IR and AFM techniques.

9

Preparation of biomimetic superhydrophobic coating on mild steel

Jeyasubramaniam K., Sathiyendran R.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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Vol. 74, nr 1

11--14

EN

Purpose: Superhydrophobic surface has many special functions and is widely investigated by researchers. Mild steel is one among the practice metals and plays an important role in all industrial applications. In this work, a simple method was used to generate superhydrophobic sueface on steel plates by electroless deposition of zinc followed by electrochemical deposition of stearic acid. Design/methodology/approach: Scanning electron microscope (SEM) and Contact angle Goniometer were used for characterize the coated sample. Findings: The fabricated surfaces were stable against acidic solutions was evident from the weight loss studies. Given their strong water repulsive properties, superhydrophobic coatings are an ideal candidate for slowing down corrosion of the metal layer. Practical implications: These results will aid in the conclusion of coating done on the specimen and also show that the as-prepared superhydrophobic surface has obvious anticorrosion effect in typically corrosive solution and naturally humid air. The approach is timesaving and cheap, and it is supposed to have a promising future in industrial fields.

10

Corrosion inhibition of mild steel in HCl solution by Tinidazole

Reza I., Saleemi A.R., Naveed S.

Polish Journal of Chemical Technology

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2011

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Vol. 13, nr 1

67-71

EN

Tinidazole, a pharmaceutical compound has been investigated with reference to the inhibition of mild steel acidic corrosion in 1 molar HCl by means of weight loss and electrochemical measurements. The outcomes attained at 30°C revealed that the Tinidazole had obtained 90% inhibition efficiency at 400 ppm concentration. These results explain that the inhibition process occurs by means of adsorption. The inhibitor molecules adsorb on the surface of the metal, following Langmuir's adsorption isotherm. Potentiodynamic polarization measurements established that Tinidazole is an inhibitor of a mixed type. An appropriate equivalent electric circuit for modeling and the analysis of impedance data to give a better explanation of the process of corrosion inhibition have been proposed.

11

Comparison of experimental and simulation results of 2D-draw-bend springback

Da Sisva Botelho T., Bayraktar E., Inglebert G.

Journal of Achievements in Materials and Manufacturing Engineering

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2006

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Vol. 18, nr 1-2

275--278

EN

Purpose: This paper presents the results of experimental, analytical and numerical studies of draw-bend springback on the response of steel blank strips. Design/methodology/approach: Springback, the elastically-driven change of shape of a part after forming, has been simulated with 2-D plane strain finite elements model (ABAQUS). Springback simulations compared with experimental test results under some test conditions and also sidewall curls were further discussed in this paper. Findings: The results validate the finite element approach as a trustworthy tool for predicting the springback parameters for a given set of stamping conditions and material properties. Research limitations/implications: This model is a simple and an efficient way to take apart the responsibilities of the steel maker for the selection of steel to be used and sheet stamping designer for the selection of the forming conditions to work in a safety zone in order to increase the reliability of the stamped structures. Originality/value: Experimental and finite element analyses have been conducted on blank strips of Hadfield steel (high strength steel) and Mild steel with similar operational conditions.