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Investigation of the Impact of Face Milling Parameters on the Roughness of the Machined Surface for 1.4301 Steel

Bembenek Michał, Dzienniak Damian, Dzindziora Agnieszka, Sułowski Maciej, Ropyak Liubomyr

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 4

299--312

EN

The objective of this research was to analyze how different milling parameters impact the roughness of the surface produced during the machining process. Kinematic parameters, such as cutting speed and feed per tooth, as well as geometric parameters, such as axial and radial depth of machining, were considered in various configurations to determine which one had the greatest impact on the surface quality of 1.4301 stainless steel (also known as AISI 304, among other designations). This type of steel is commonly used in a number of industries, such as construction, automotive, food, chemical, decoration, oil, and petrochemical, owing to its favorable properties. It is also relatively cheap. The analyzed roughness parameters included Ra, Rq, Rz, Rt, which, considered collectively, provide a comprehensive picture of the overall surface quality. Based on the results, feed per tooth is the one parameter that was to a large degree responsible for the overall quality roughness of the surface of the analyzed samples. The remaining tested parameters also had an impact on the surface quality, which resulted in a dynamic increase or decrease in roughness (extremes), but not to the same degree as in the case of feed per tooth. At one point, for a relatively low axial depth of cut, a sudden increase in the resulting roughness was recorded.

2

Influence of Water-Jet on Micro-Formed Parts Process via Nano-Indentation and SEM Analysis

Quaisie James Kwasi, Yamba Philip, Mwinteribo Tabie Vitus, Akayeti Anthony, Kukurah Jamal-Deen, Mohammed Abdul-Hamid

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 2

353--361

EN

Based on the experimental study of cavitation water jet impact on microforming, a single round hole micro-die was used in this paper. The effect of different process parameters on the performance of 304 stainless steel foil was examined, which involves the nanometer hardness, and elastic modulus. The nano-indentation tester was used to test the nano-hardness of the formed part, and the performance of the workpiece before and after the impact was analyzed. The nano hardness and elastic modulus increased significantly with an increase in the incident pressure. When the incident pressure was 20 MPa and the impact time of 5 min, the hardness increased by at least 122%, and the elastic modulus increased by at least 76%. After the cavitation water jet shocked the metallic foil of the SEM analysis and the results indicated that, as the incident pressure increases, the surface morphology of the formed part changes from approximately spherical to spherical, and the spherical roundness increases. In addition, there were different degrees of defects at the bottom of the formed part, and as the incident pressure increased, the bottom defects became more and more obvious, from micro-cracks to micro-layer cracks.

3

Superkondensatorowa elektropulsacyjna metoda zwiększenia odporności zmęczeniowej wyrobów wykonanych z blachy austenitycznej

Zimniak Z., Lesiuk G., Wiśniewski W.

Przegląd Spawalnictwa

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2018

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R. 90, nr 2

35--37

PL

Celem prowadzonych badań było zbadanie wpływu zastosowania pulsacyjnego przepływu prądu o dużej gęstości (z wykorzystaniem zasilacza superkondensatorowego) na żywotność zmęczeniową badanych próbek. W tym celu przeprowadzono analizy eksperymentalne dla grupy próbek niepoddanych pulsacji prądowej i po ekspozycji prądowej. W pracy przedstawiono wyniki badań dla stali austenitycznej AISI 304 (0,04% C, 1,2% Mn, 18,16% Cr, 8% Ni, 0,335% Mo, 0,041% Si) w zakresie ograniczonej wytrzymałości zmęczeniowej. Eksperymenty prowadzono na próbkach płaskich z karbem (SENT – Single Edge Notched Tension Specimen) U-kształtnym wykonanym metodą elektroiskrowego drążenia (W = 15 mm, t = 0,5 mm, a0 = 2,5 mm). Zastosowano impulsy prądowe dodatnie o różnych czasach trwania oraz częstotliwościach. Badania przeprowadzono na pulsatorze hydraulicznym MTS 810, sterowano stałą amplitudą siły Fmax = 1100 N. Uzyskane, wstępne wyniki zachęcają do dalszych analiz i studiów nad szeregiem czynników pozwalających wykorzystać zjawisko elektropulsacji wysokoprądowej w kontekście zwiększania trwałości zmęczeniowej narzędzi lub wyrobów otrzymywanych obróbką plastyczną.

EN

The purpose of the study was to investigate the effect of the use of high density pulsed current (using supercapacitor) on the fatigue life of the tested specimens. For this purpose, experimental analyses were carried out for a two group of samples: without current pulsation and after current exposure. The results of the study for AISI 304 steel (0.04% C, 1.2% Mn, 18.16% Cr, 8% Ni, 0.335% Mo, 0.041 %Si) for fatigue strength were presented. The experiments were performed on single edge notched tensile specimen (SENT) with U-shaped electro-drilling (W = 15 mm, t = 0.5 mm, a0 = 2.5 mm). Positive current pulses with different durations and frequencies were used. The tests were carried out on a hydraulic pulsator MTS 810, controlled by a constant force amplitude Fmax= 1100 N. Obtained initial results encourage for further analyzes and studies with a number of factors that allow the use of high current electricity in the context of increasing the fatigue life of tools or products obtained by plastic metal forming.

4

Porównanie wydajności oraz jakości spawania zmechanizowanego i zautomatyzowanego metodą TIG wspornika ze stali AISI 304

Piechowski M., Klupczyński K., Kiciński F.

Przegląd Mechaniczny

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2018

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nr 6

17--22

PL

W artykule zawarto porównanie produkcji elementu typu wspornik przy wykorzystaniu metod spawania zmechanizowanego oraz zautomatyzowanego. Badaniu poddano odkształcenia w wyrobie wynikające z sekwencji operacji spawalniczych oraz wydajność procesu. Porównano czasy wykonania dla obu metod produkcyjnych, a także wykazano różnice czasu przy wykonaniu partii logistycznej wyrobu. Pomiary oraz wyliczenia wykazują przewagę metody zautomatyzowanej ze względu na możliwość wykonania czynności jednocześnie (metoda zautomatyzowana w przeciwieństwie do zmechanizowanej nie wymaga angażowania operatora w pełnym wymiarze jego dostępnego czasu). Ze względu na równoległe wykonanie spoin leżących naprzeciw siebie, w metodzie zautomatyzowanej uzyskano znacznie niższe odkształcenia.

EN

The article compares the mechanized and automated welding methods used for the manufacturing of a hanger type product. The research focused on the product distortion caused by welding sequence as well as on the process efficiency. The cycle times were compared for both production methods, and the differences in the completion times were found when manufacturing the entire batch size. Both measurements and calculations demonstrated the advantage of the automated method which allowed simultaneous operations. Unlike the mechanized method, the automated method did not require the full time availability of the operator. Moreover, due to the fact that the opposite welds could be done in parallel, the automated method proved to cause less distortion.

5

Effect of the post-weld surface condition on the corrosion resistance of austenitic stainless steel AISI 304

Rogalski G., Jurkowski M., Łabanowski J., Fydrych D.

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2018

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Vol. 62, No. 1

24--29

PL

Na powierzchni spawanych elementów ze stali odpornych na korozję (nierdzewnych) powstają barwy nalotowe. Usuwanie pogrubionych warstewek tlenków ze stali pracujących w temperaturach nieprzekraczających 300°C jest konieczne i wiąże się z przywróceniem stali nierdzewnej wysokiej odporności na korozję. W artykule przedstawiono badania wpływu metody usuwania warstw nalotowych po procesie spawania na odporność korozyjną austenitycznej stali nierdzewnej AISI 304. Ustalono, że najlepszą metodą osiągnięcia wysokiej odporności korozyjnej jest stosowanie właściwego procesu pasywacji.

EN

Surfaces of welded elements made of corrosion-resistant (stainless) steels develop temper colours. The removal of thickened oxide layers off steels exposed to temperatures below 300°C is necessary and en-tails the restoring of high corrosion resistance of the stainless steel. The article presents tests concerned with the effect of a method applied to remove post-weld temper on the corrosion resistance of austenitic stainless steel AISI 304. It was ascertained that the most favourable method enabling the obtainment of high corrosion resistance involved the use of an appropriate passivation process.

6

Automated Laser Welding of AISI 304 Stainless Steel by Disk Laser

Lisiecki A., Kurc-Lisiecka A.

Archives of Metallurgy and Materials

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2018

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Vol. 63, iss. 4

1663--1672

EN

The automated laser welding process of 2.0 mm thick sheets of AISI 304 stainless steel was investigated. The disk laser with a beam spot diameter of 200 μm was used for bead-on-plate and next for autogenous butt joints welding. The influence of basic welding parameters such as laser power, welding speed, and focal spot position on fusion zone configuration, quality of joints, microstructure changes, and microhardness distribution across the joints were analysed and presented in this paper. The results have shown that stiffening of the 2.0 mm thick sheets is crucial for providing high quality and reproducibility of butt joint in a case of AISI 304 stainless steel due to relatively low thermal conductivity and simultaneously high thermal expansion. Relevant drop of microhardness in the weld zone was observed. The mean value of microhardness of the base metal was 230 HV0.1, while the microhardness in fusion zone of the test welds was ranged from 130 to 170 HV0.1. Additionally the microstructure changes in the weld metal and also in the heat affected zone of test joints is described.

7

Trwałość spawanych instalacji wodnych wykonanych z nierdzewnych stali austenitycznych

Łabanowski J., Jurkowski M., Fydrych D., Rogalski G.

Przegląd Spawalnictwa

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2017

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R. 89, nr 8

35--40

PL

W artykule przedstawiono dwa przypadki przedwczesnych uszkodzeń spawanych instalacji wodnych wykonanych ze stali odpornej na korozję. W celu ustalenia przyczyn uszkodzenia instalacji przeprowadzono badania metalograficzne makro- i mikroskopowe oraz mikroanalizę składu chemicznego EDS na próbkach pobranych z reprezentatywnych miejsc. Wykazano, że głównymi przyczynami awarii rurociągów wody pitnej były niezgodności spawalnicze, które przyczyniły się do korozyjnego uszkodzenia instalacji. Na podstawie uzyskanych wyników sformułowano wnioski dotyczące przyczyn uszkodzenia odcinków rurociągów oraz zalecenia dotyczące trwałości spawanych instalacji wodociągowych ze stali nierdzewnych austenitycznych.

EN

Two cases of premature failure of welded water supply pipelines made of stainless steel are presented in this article. Metallographic examinations and EDX microanalysis of the corrosion products on selected samples has been carried out to determine causes responsible for failures. Examinations revealed that main causes of welded water supply pipelines failure were welding imperfections which lead to the corrosion damage. On the basis of received results conclusions about causes of pipelines damages and recommendations for durability of welded water supply pipelines made of austenitic stainless steels were formed.

8

The study of TRIP effect in an austenitic stainless steel AISI 304

Lischka F. T., de Oliveira C. A. S.

Journal of Achievements in Materials and Manufacturing Engineering

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2015

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Vol. 71, nr 1

34--38

EN

Purpose: This study investigated the deformation effect in variation of α′-martensite volume fraction and its microstructural characteristics in an austenitic stainless steel AISI 304. Design/methodology/approach: The study was fulfilled through magnetic analysis with Vibrating Sample Magnetometer (VSM) and transmission electron microscopy (TEM). Findings: The presence of austenite, ε-martensite and α′, and that the nucleation of ε-martensite occurs in stacking faults, grain boundaries and accumulated dislocations in grain boundaries. Already α′-martensite nucleates in stacking faults, twinning edges, deformation bands and mechanical twinning. In addition, the magnetic martensite takes shape directly from the austenite. Research limitations/implications: A suggestion for future research is to increase the number of samples for deformations larger than 0.30 equivalent strain, due to the significative percentage of α′-martensite from this strain. Practical implications: A crescent parabolic behavior in relation between percentage of α′-martensite and equivalent deformation was observed by VSM. The increase of equivalent deformation increases the austenite transformation in α′-martensite. Originality/value: The behavior in relation between percentage of α′-martensite and equivalent deformation, and the study of α′-martensite nucleation.

9

The Effect of Shielding Gas Composition and Orbital TIG Welding Parameters on the Dimensions and Quality of Austenitic Stainless Steel Pipe Girth Welds

Niagaj J., Jędrusiak A.

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2015

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Vol. 59, No. 1

5--12

EN

The article presents the results of orbital welding of AISI 304 (1.4301) austenitic stainless steel pipes using a closed welding head. The article-related tests revealed that an increase in a helium content in a shielding gas mixture increases a penetration depth with a little impact on a weld width. It was also found that an increase in welding current and a decrease in a welding rate can ensure full penetration, yet at the same time it can lead to the formation of imperfections in the form of an incompletely filled groove at 9h and 12h and/or an intermittent undercut at 3h. Welded joints of austenitic stainless steel pipes are characterised by the highest concentration of imperfections at 3h and 9h (incompletely filled grooves and intermittent undercuts) regardless of the type of a shielding gas used.

PL

Przedstawiono wyniki badań spawania orbitalnego rurek z austenitycznej stali nierdzewnej AISI 304 (1.4301) z zastosowaniem głowicy zamkniętej. Wykazano, że zwiększenie zawartości helu w mieszance osłonowej powoduje wzrost głębokości wtopienia przy niedużym zwiększeniu szerokości spoin. Stwierdzono ponadto, że wzrost natężenia prądu lub spadek prędkości spawania może zapewnić pełny przetop, ale jednocześnie przyczynić się do powstawania niezgodności w postaci wklęśnięcia lica na godzinie 9. i 12. i/lub podtopienia lica na godzinie 3. Złącza rur ze stali austenitycznej cechują się najwyższą koncentracją niezgodności spawalniczych na godzinach 3. i 9. (wklęśnięcie lica i podtopienie lica), niezależnie od rodzaju gazu osłonowego.

10

Evaluating the machinability of AISI 304 stainless steel using alumina inserts

Xavior M A

Journal of Achievements in Materials and Manufacturing Engineering

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2012

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Vol. 55, nr 2

841--847

EN

AISI 304 austenitic stainless steel is generally regarded as difficult to machine steels on account of their high strength, high work hardening tendency and poor thermal conductivity. The machinability of AISI 304 was investigated by some researchers using uncoated and coated carbide inserts, but its machinability using advanced cutting inserts like alumina was not explored adequately. Therefore, in this paper the machinability of AISI 304 is being evaluated by machining (CNC turning process) the work material using alumina inserts. The machinability is evaluated in terms of surface finish achieved on the work piece, tool wear encountered and tool life achieved by the inserts for various machining time and the cutting zone temperature generated during the process.

11

Friction Stir Welding of austenitic stainless steels

Meran C., Canyurt O. E.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 43, nr 1

432--439

EN

Purpose: Friction Stir Welding (FSW) was applied austenitic stainless steels that is difficult to weld using FSW technique. Proper weld can be obtained by using appropriate welding parameter. In this paper, the effect of different tool rotational speeds, traverse speeds, compressive tool forces, and tool angles was investigated. Design/methodology/approach: The dimension of 3 mm x 75 mm x 150 mm two stainless steel plates were used and butt welded by FSW method using 7.5 kW vertical head milling machine. All welded test specimens were prepared perpendicular to the weld line in order to determine the mechanical properties and tested with 12 MPa/sec stress rate under stress control using a servo-hydraulic Instron 8801. Microstructure of the welding zone and macrograph of the heat affected zone was investigated by SEM. Findings: The average grain size in the SZ was between 3 and 7 μm, which is smaller than that in the BM. The average grain size in the HAZ was about 20 μm, which is half of that in the BM. Fine-grained microstructures are present the welded area. The dark bands observed in the weld zone were also detected the microstructure of the transition zone. Dark and narrow bands do not consist of pores or cavities. It was determined that these bands do not process an ultra fine-grained microstructure. They are Cr2O3 oxide layers which over the surface of stainless steels may have been ruptured during friction stir welding and may form bands inside the welding bead due to stirring. Research limitations/implications: The proper cooling system helps to prevent the stirrer tool from the deformation. Practical implications: The strength of the welded zone of AISI 304 stainless steel can be easily found by implementing welding design parameters and high quality joints can be obtained. Originality/value: This study was performed in the frame of the TUBITAK project no 106M504, „Friction Stir Weldability of Stainless Steels and Investigation of the Affected Parameters on the Welding Quality”.

12

Inverse analysis of a plane strain compression test results for the purpose of material mechanical and microstructural properties study

Aksenov S., Chumachenko E. Csc., Kliber J. Csc., Fabik R. Ph.D.

Hutnik, Wiadomości Hutnicze

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2009

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Vol. 76, nr 8

555-557

EN

Knowledge of mechanical and microstructural properties of a material is extremely important for performing the numerical analysis which is using for investigation of many metal-forming processes. The plain strain compression test (PSCT) is now generally accepted as one of the most reliable methods for the generation of flow stress data and microstructural investigation of flat rolling. However, the inhomogeneous character of deformation in local zones of a specimen makes it difficult to interpret the results of such tests. In this work, the inverse method has been applied for determination of flow-stress and microstructural data by analyzing of PCST results. A method for determination of static recrystallization kinetics parameters which makes it possible to take advantage of PSCT and at the same time reduce the number of experiments is presented. It based on the comparison of an average grain size in the local areas of a specimen with the thermo-mechanical characteristics obtained for these areas by finite element simulation. Thus, the parameters of static recrystallization (SRX) kinetics for the AISI304 stainless still at 1000 °C have been obtained by presented method from the results of five laboratory experiments.

PL

Znajomość mechanicznych i mikrostrukturalnych właściwości materiału jest niezmiernie ważna dla wykonywania analizy numerycznej w celu przewidywania efektów różnych procesów kształtowania metali. Prosta próba ściskania w płaskim stanie odkształcenia (PSCT) jest ogólnie przyjętą i jedną z najczęściej stosowanych metod wyznaczania charakterystyk naprężenia uplastyczniającego i przewidywania mikrostruktury dla procesu płaskiego walcowania. Jednakże niejednorodny charakter odkształcenia lokalnego ściskanej próbki stwarza trudności w interpretacji wyników tego rodzaju prób. W pracy przedstawiono zastosowanie metody analizy odwrotnej do przewidywania charakterystyk naprężenia uplastyczniającego oraz mikrostruktury oparte na analizie wyników prostej próby ściskania. Prezentowana metoda poprzez przewidywanie parametrów kinetyki rekrystalizacji statycznej umożliwia wykorzystanie zalet prostej próby ściskania, a tym samym ogranicza czas i liczbę niezbędnych doświadczeń. Jest to realizowane na podstawie porównania wielkości średniego ziarna w lokalnych strefach odkształcenia próbki ściskanej z charakterystykami stanów termomechanicznych panujących w tych strefach, wyznaczonymi przy zastosowaniu symulacji numerycznej metodą elementów skończonych (MES). W ten sposób zostały określone parametry kinetyki rekrystalizacji statycznej (SRX) dla stali nierdzewnej AISI 304 w temperaturze 1000 °C przy zastosowaniu prezentowanej metody dla pięciu prób laboratoryjnych.