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1

The Effect of Brushing on Residual Stress and Surface Roughness of EN AW-2024-T3 Aluminum Alloy Joints Welded Using the FSW Method

Bucior Magdalena, Kluz Rafał, Kubit Andrzej, Ochał Kamil

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 1

86--93

EN

This article presents the influence of the brushing process on residual stress and surface roughness of EN AW-2024-T3 aluminum alloy joints welded using the Friction Stir Welding (FSW) method. Butt joints with thicknesses of 2 mm were brushing with using ceramic brush. The aim of the study was to find optimal parameters of the brushing process, which would significantly improve the functional properties of welded joints. The experiments were carried out in two steps. In the first stage of the research, the feed rate was changed in the range f = 40 ÷ 120 mm / min with a constant brushing depth d = 0.5 mm. The roughness decreased from Sa = 5.285 µm for the specimen after welding to Sa = 2.460 µm for the f = 120 mm/min and d = 0.5 mm. The change in the parameters of the brushing process did not have a significant impact on the state of residual stresses. Hence, in the second step, the brushing depth was increased in steps of 0.1 mm. The best properties were obtained for f = 120 mm / min and d = 0.6 mm (variant 6A), where roughness was Sa = 0.443 µm and compressive stresses σ = -118 MPa.

2

Geometrical Accuracy of Threaded Elements Manufacture by 3D Printing Process

Budzik Grzegorz, Dziubek Tomasz, Kawalec Andrzej, Turek Paweł, Bazan Anna, Dębski Mariusz, Józwik Jerzy, Poliński Przemysław, Kiełbicki Mateusz, Kochmański Łukasz, Oleksy Mariusz, Cebulski Józef, Paszkiewicz Andrzej, Kuric Ivan

Advances in Science and Technology. Research Journal

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2023

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Vol. 17, no 1

35--45

EN

Additive processes allow for almost any manufacturing of screw-threaded joint elements. However, this requires knowledge of the geometrical relationships of a threaded itself and the strength of materials from which the screw-threaded joint is made. Thanks to the development of research models and conducting tests related to dimensional accuracy and surface roughness, it was possible to test the models made by MEX process of ABS-M30, PLA, ABS, PETG materials, and PolyJet process from RGD720 polymer material.In the case of measurements carried out on the MarSurf XC20 system, the internal and external thread profile was obtained.Measurements of the surface roughness of the printed models were made using the Taylor Hobson TalyScan 150 profilometer. Based on the obtained surface, following the ISO 25178-2 standard, selected parameters were determined.

3

Experimental Study of Surface Roughness Effect on the Rheological Behavior of MR Fluid

Stępień Barbara, Horak Wojciech

Tribologia

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2022

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nr 4

73--83

EN

Magnetorheological (MR) fluids are classified as smart materials. They are non-homogeneous substances of complex composition and are characterised by complex rheological properties. In addition, the characteristics of their behaviour can be actively affected by the magnetic field, both in terms of its value and spatial orientation. This paper presents the results of shear stress measurements of a commercial magnetorheological fluid using a plate-plate type geometry with a modified working surface. The purpose of the study was to determine the effect of changing the roughness of the measuring plate on the obtained shear stress results. Controlled shear rate tests and Magneto Sweep measurements were carried out for three MR fluid layer heights. The tests were carried out at magnetic field induction in the range of 0 to 680 mT. The study showed that the measurement system's geometric parameters significantly affect the MR fluid's behaviour under test. It was shown that increasing the surface roughness can increase or decrease the measured value of shear stress depending on the test parameters.

PL

Ciecze magnetoreologiczne (MR) zaliczane są do grona materiałów inteligentnych. Są to substancje niejednorodne o złożonym składzie i charakteryzują się złożonymi właściwościami reologicznymi. Ponadto charakterystyki ich zachowania mogą być aktywnie kształtowane przez pole magnetyczne, zarówno ze względu na jego wartość, jak i orientację przestrzenną. W pracy przedstawiono wyniki pomiarów naprężenia stycznego komercyjnej cieczy MR z wykorzystaniem geometrii pomiarowej typu płytka–płytka o modyfikowanej powierzchni roboczej. Celem badań było określenie wpływu zmiany chropowatości płytki pomiarowej na uzyskiwane wyniki naprężeń ścinających. Przeprowadzono badania z kontrolowaną szybkością ścinania oraz pomiary typu Magneto Sweep dla trzech wysokości warstwy cieczy MR. Badania przeprowadzono przy indukcji pola magnetycznego w zakresie 0 do 680 mT. Badania wykazały, że parametry geometryczne układu pomiarowego istotnie wpływają na zachowanie się badanej cieczy MR. Wykazano, że w zależności od parametrów badania zwiększenie chropowatości powierzchni może powodować zwiększenie lub zmniejszenie rejestrowanej wartości naprężeń stycznych.

4

Analysis of the influence of turning parameters of CuZn39Pb3 and AW 6060 materials on surface roughness

Tomczewski Leszek, Muszyńska-Pałys Jagoda

Technologia i Automatyzacja Montażu

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2022

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nr 2

8--14

EN

The article presents an analysis of the turning parameters of two non-ferrous materials. The tested materials were: brass CuZn39Pb3 and aluminum alloy AW 6060. A Kyocera turning knife and a WNMG 080404 AH plate were used to make the samples. Three parameters were tested: rotational speed, feed and depth of cut at three levels of variability. The roughness parameters Ra and Rz were selected for the analysis. On the basis of the obtained results, it was shown that the feed used during machining has the greatest influence on roughness, while the change of depth or cutting speed does not cause significant differences in roughness.

PL

W artykule przedstawiono analizę parametrów toczenia dwóch materiałów nieżelaznych. Materiałami poddanymi badaniom były: mosiądz CuZn39 Pb3 i stop aluminium AW 6060. Do wykonania próbek użyto noża tokarskiego firmy Kyocera i płytki WNMG080404AH tej firmy. Badaniom poddano trzy parametry: prędkość obrotową, posuw i głębokość skrawania na trzech poziomach zmienności. Do analizy wybrano parametr chropowatości Ra i Rz. Na podstawie uzyskanych wyników wykazano, że największy wpływ na chropowatość ma posuw stosowany podczas obróbki, natomiast zmiana głębokości czy tez prędkości skrawania nie powoduje znaczących różnić w chropowatości.

5

Evaluation of surface roughness of anatomical structures models of the mandible made with additive techniques from selected polymeric materials

Turek Paweł

Polimery

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2022

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Vol. 67, nr 4

162--167

EN

The influence of polylactide (PLA), polycarbonate (PC), polyacrylic photo resins and polyamide 11 (PA11) on the surface roughness of anatomical models structures of the mandible made with additive techniques was investigated. Measurements of the model surfaces geometric structure were carried out using a 3D contact profilometer. Selected roughness parameters and three-dimensional visualization of the tested models surface roughness are presented.

PL

Zbadano wpływ polilaktydu (PLA), poliwęglanu (PC), żywic foto poliakrylowych i poliamidu 11 (PA11) na chropowatość powierzchni modeli struktur anatomicznych żuchwy wykonanych technikami przyrostowymi. Pomiary struktury geometrycznej powierzchni modeli przeprowadzono przy użyciu profilometru stykowego. Przedstawiono wybrane parametry chropowatości oraz trójwymiarowe wizualizacje chropowatości powierzchni badanych modeli.

6

Effect of calcite and mica contents in nepheline syenite samples on the ceramic body sintering behaviours and surface roughness

Durgut Emrah, Cinar Mustafa, Ozdemir Orhan

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 5

art. no. 149179

EN

In this study, the effects of calcite and mica contents in nepheline syenite (NS) samples beneficiated by high intensity dry magnetic separation and flotation methods on ceramic bodies were investigated in detail. The NS samples were, first, sintered to observe the physical and surface roughness properties, and characterized based on the change of NS samples such as color, shrinkage, water absorption, and surface roughness after the sintering process. L-a-b color and Ra, Rz, Rt values for the NS samples were determined. The decrease in calcite and mica contents affected the surface of sintered specimens positively by reducing roughness values. Additionally, the water absorption values were found to be directly proportional to Ra values for unglazed surfaces. In conclusion, calcite and mica minerals in NS samples negatively affected surface quality by forming pinholes due to dehydroxylation and outgassing reactions in the sintering process.

7

Wpływ wybranych czynników na efektywność procesu szlifowania

Kotwis Mirosław, Żyłka Wojciech

Obróbka Metalu

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2022

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Nr 4

46--49

PL

W artykule przedstawiono dalsze rezultaty badań eksperymentalnych dotyczących wpływu wybranych czynników procesu szlifowania na stan powierzchni elementów obrotowych. Opis pierwszej części zawarty jest w numerze 3/2022. W tej części analizowano wpływ granulacji ziaren ścierniwa na chropowatość obrabianych powierzchni, a także związek między parametrami obciągania ściernicy a stanem powierzchni po obróbce. Stwierdzono zróżnicowaną istotność tych czynności.

EN

In the paper, further carried out experimental studies on the effects of selected grinding process factors on surface properties were presented. The description of the first part is given in No 3/2022. This section investigations the effects of granulation of abrasive grains on the surface roughness of the treated surfaces were contained. The relationship between the parameters of the grinding wheel dressing and the condition of the surface after machining were presented too. Different relevance of these factors was found.

8

Wpływ geometrii płytek skrawających na chropowatość powierzchni w obróbce wykończeniowej

Osak Mateusz, Żyłka Wojciech

Obróbka Metalu

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2022

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nr 1

32--36

PL

W artykule przedstawiono badania wpływu geometrii płytek tokarskich na chropowatość powierzchni. Obróbce toczeniem poddano dwa rodzaje stali: 1.0503 (C45) oraz 1.6582 (34CrNiMo6) w formie wałka o średnicy Ø 50. Badano otrzymaną chropowatość powierzchni toczonych trzema rodzajami płytek DCET 11T3005R (z geometrią ostrza Wiper), WNMG080404, VBMT160404. Wyniki badań jednoznacznie wykazały, że powierzchnie obrobione płytkami typu Wiper charakteryzują się mniejszymi wartościami parametrów chropowatości niż obrobione płytkami o geometrii standardowej.

EN

In this paper investigates how the geometry of turning plates affects the surface roughness were described. Two steel types were machined: 1. 0503 (C45) and 1. 6582 (34CrNiMo6) in the form of a shaft with a diameter of Ø50. The resulting surface roughness was investigated with three plate types DCET 11T3005R (with Wiper geometry), WNMG080 404, VBMT160 404. The test results clearly showed that surfaces treated with Wiper geometry plates have lower roughness parameters than plates with standard geometry.

9

Określenie korelacji między prędkością skrawania a parametrem chropowatości Ra

Jędrzejczyk Dariusz, Mikołajczyk Jarosław Robert

Obróbka Metalu

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2022

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nr 3

11--15

PL

W pracy przedstawiono zagadnienia dotyczące określenia zależności matematycznej pomiędzy prędkością skrawania, a parametrem chropowatości Ra. Wykazano, że istnieje silna ujemna korelacja między w/w badanymi zmiennymi.

EN

In this paper investigations concerning the determination of the mathematical relationship between the cutting speed and the roughness parameter Ra were presented. A strong negative correlation between the studied variables was demonstrated.

10

Parametric model analysis, geometrical characteristics and tool trajectories to surface roughness when machining the cycloid screw by a five-axis milling machine

Pham Van Bong, Thien Nguyen Van, Nguyen Van Que, Duy Trinh Nguyen, Nguyen Duy Khanh, Tien Dung Hoang

Journal of Machine Engineering

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2022

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Vol. 22, No. 2

108--124

EN

To improve the screw machining accuracy in modern air compressors. This paper investigates three main issues during the development process for cycloid screw machining methods on five-axis CNC machine tools with high precision and efficiency. First, the theoretical basis of cycloid screw surface shaping and derivative of the final profile equation is established. Then, modeling the center trajectory and feed rate according to the cycloid screw profile is given. Next is the experimental setup and simulation of the cycloid screw machining process and discussions. The obtained surface quality prediction parameters are close to the actual measured value, which can be used as a reference model for five-axis CNC milling technology processes. All experimental results obtained by the proposed mathematical model show that a surface with good surface quality is created, meeting the requirements for surface quality. The main work can be used as references for engineers and technicians in practice.

11

Influence of different machining processes on fatigue life performance of engineered surfaces: a short review

Grzesik Wit

Journal of Machine Engineering

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2022

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Vol. 22, No. 2

18--30

EN

In this paper fundamental information on the influence of the real machined surfaces generated by different machining processes on the fatigue life of machine parts are presented. In the first part the various approaches for the assessment of the stress concentration factor and the correction of a fatigue life limit are discussed. In the second part the results of standard fatigue tests are compared with computed data and predictions using FEM based simulations. The effect of surface discontinues (valleys) in the real surface profiles is related to engineered parts made of different materials including steels, aluminium alloys, aerospace alloys and composites.

12

Analysis of solid and ionic surface reaction form to surface quality when using chemical-mechanical slurry polishing

Duc Le Anh, Hieu Pham Minh, Mai Nguyen Trong, Trong Thai Van, Quang Nguyen Minh

Journal of Machine Engineering

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2022

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Vol. 22, No. 4

82--94

EN

The process of removing machining residues using chemical-mechanical slurry (CMS) has an important place in the creation of ultra-precise components in optical devices. Based on this feature, this work investigates the efficiency of the CMS polishing process by comparing the surface reaction modes by the ionic and solid reaction modes when polishing the yttrium aluminum garnet (YAG) and sapphire crystal. The study procedures were conducted to clarify the polishing performance corresponding to these two reaction types. The obtained experiments results show that the balance between the mechanical effect process using CMS polishing technology with chemical effect can be achieved with the ionic reaction mode. The results also show that the ionic surface reaction modes give more uniform material removal than the solid reaction on YAG and sapphire crystal surfaces. Therefore, the surface quality when polished by CMS technology with ionic surface reaction modes is better than that of solid surface reaction.

13

Optimisation of variation coolant system techniques in machining aluminium alloy Al319

Zainal Ariffin S., Efendee A. M., Redhwan A. A. M., Alias M., Arifuddin A., Kamrol Amri M., Mohd Ali M., Khalil K., Aminullah A. R. M., Hasnain A. R., Baba N. B.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 113, nr 2

72--77

EN

Purpose Cutting parameters are often chosen for machining by machine operators in the industry. The experience and efficiency of the machine operator in producing a quality product are frequently used to decide parameter selection—low productivity results from improper parameter selection, inefficient machining, and technological issues. Today's key issues in the machining industry are focusing on increasing machining performance on surface roughness while minimising coolant usage. The study's objective is to enhance the performance of the nozzle lubrication system during the turning operation of an aluminium alloy 319 workpieces (Al319) to generate good surface roughness by applying turning parameters such as cutting speed, feed rate, and the depth of cut. Design/methodology/approach Response Surface Method (RSM) was used to create the experimental method for this investigation, carried out using a CNC lathe machine with two axial movements and a wet cooling nozzle with a size of 1.0 mm. Synthetic soluble lubricants, Al2O3-coated cemented carbide inserts, and Aluminium alloy 319 were utilised as cutting tools and workpiece materials. Findings To study the influence of cutting parameters on surface roughness, the Analysis of Variance (ANOVA) approach was utilised while the response surface method was performed to achieve an optimum machining performance (RSM). When comparing dry and wet cooling systems, the size of 1.0 mm nozzle shows appropriate surface roughness. According to the ANOVA analysis, the key factor impacting the surface roughness as machining performance in lubrication technique experiments was the utilisation of 1.0 mm nozzle size. Research limitations/implications The findings of combination machining parameters at a cutting speed of 270 m/min and a cutting depth of 0.60 mm at a feed rate of 0.08 mm/min offered the best results, achieving a surface roughness, Ra of 0.94 µm. Practical implications The use of coolant size nozzle 1.0 mm technology combined with the use of correct machining parameters can improve machining cuts. Originality/value The novel size of 1.0 mm nozzle in this current research is also valuable for reducing and increasing productivity in the machining business, as well as reducing dependency on machining operators' experience and abilities.

14

Evaluation of effect of machining parameters on surface roughness in drilling of glass fiber reinforced polymer (GFRP) composite material with different drill bits

Altin Karataş Meltem

Composites Theory and Practice

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2022

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R. 22, nr 2

87--91

EN

In the present study, the arithmetical mean roughness (Ra) values obtained as a result of drilling glass fiber reinforced polymer (GFRP) composite material produced in fiber orientation angles (0º/90º) with different drill bits in a 5-axis CNC controlled vertical machining center, were analyzed. The experimental design was applied with the Taguchi method. The drilling experiments were performed using Minitab 19 software according to the Taguchi L18 orthogonal array. The test results were evaluated based on the signal-to-noise (S/N) ratio. Two different drill bits (HSS and carbide), three different spindle speeds (750, 1000, 1500 rpm) and three different feed rates (0.05, 0.10, 0.15 mm/rev) were selected as the control factors. The effect levels of the control factors on Ra were found by applying analysis of variance (ANOVA). A confidence level of 95.62% was obtained with ANOVA analysis. The lowest Ra value was 1.279 μm at the spindle speed of 1500 rpm and the feed rate of 0.05 mm/rev using a carbide drill bit. The drill bit type was obtained as the parameter with the highest effect with a rate of 61.33%.

15

Study on the Effect of in Situ Surface Treatments of Medical Microfluidic Systems Obtained Through Additive Manufacturing

Csapai Alexandra, Țoc Dan-Alexandru, Pașcalău Violeta, Toșa Victor, Opruța Dan, Popa Florin, Popa Catalin

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 3

1071--1078

EN

This paper presents a comparative study on the effects of the in-situ surface modifications performed on “H” type microfluidic systems obtained via additive manufacturing. The microsystem was printed using a polylactic acid filament on an Ender-5 Pro printer. The surface modification of the main channel was done using chloroform by two different methods: vapor smoothing and flushing. The obtained surface roughness was studied using an optical microscope and the ImageJ software, as well as scanning electron microscopy. The effect of the channel surface treatment upon the characteristics of the fluid flow was assessed. The microfluidic systems were used for the dynamic study of biofilm growth of Candida albicans (ATCC 10231). The influence of the surface roughness of the main channel on the formation and growth of the biofilm was studied using quantitative methods, scanning electron microscopy imaging as well as optical coherence tomography.

16

Effect of Flap Peening Speed on the Surface Quality and Micro Hardness of Aircraft Aluminum Alloys

Shaban Nabeel Abu, Alshabatat Nabeel, Al-Qawabah Safwan

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 3

855-862

EN

Flap peening (FP) is a cold working technique used to apply a compressive force using small shots, this will lead to enhance the surface properties that it can sustain for long life during working conditions. In this study, several aircraft aluminum alloys materials namely; 2219 T6, 2024 T6, 7075 T6, and 6061 T6 were flap peened under different rotational speeds. The effect of rotational speed on the average surface roughness (Ra) and average surface micro hardness have been investigated. As seen by the Scanning Electron Microscope SEM phots that the hardness of peened layer is increased. It was found that as the flap peening speeds increase the percent change in surface roughness (Ra) increases, and the percent change in surface micro hardness decreases. The maximum increase in Ra occurs in 2219 T80 and the minimum in 6061 T6 alloys, and for hardness, it is reported that the maximum occurs in 6061 T6 and the minimum in 2019 T80 alloy.

17

Assessing Machinability and Surface Characteristics of a Shape Memory Alloy (SMA) Processed through Wire Electro Spark Erosion Method

Ebenezer George, Khan Adam M., Chellaganesh Duraipandi, Winowlin Jappes J. T., Haider Julfikar

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 3

921--930

EN

In this paper, a study was carried out to investigate the surface roughness and material removal rate of low carbon NiTi shape memory alloy (SMA) machined by Wire Electro Spark Erosion (WESE) technique. Experiments are designed considering three parameters viz, spark ON time (SON), spark OFF time (SOFF), and voltage (V) at three levels each. The surface roughness increased from 2.1686 μm to 2.6869 μm with an increase in both SON time, SOFF time and a decrease in voltage. The material removal rate increased from 1.272 mm3/min to 1.616 mm3/min with an increase in SON time but a varying effect was observed the SOFF time and voltage were varied. The analysis revealed that the intensity and duration of the spark had an unswerving relation with the concentration of the microcracks and micropores. More microcracks and micropores were seen in the combination of SON = 120 μs, voltage = 30 V. The concentration of the microcracks and micropores could be minimised by using an appropriate parameter setting. Therefore, considering the surface analysis and material removal, the low carbon NiTi alloy is recommended to machine with 110 μs - 55 μs - 30 V (SON - SOFF - V respectively), to achieve better surface roughness with minimal surface damage.

18

Wear and surface characteristics on tool performance with CVD coating of Al2O3/TiCN inserts during machining of Inconel 718 alloys

Agari Shailesh Rao

Archive of Mechanical Engineering

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2022

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LXIX, nr 1

59--75

EN

The Inconel 718 alloys, which are primarily temperature resistant, are widely used in aviation, aerospace and nuclear industries. The study on dry cutting processes for this alloy becomes difficult due to its high hardness and low thermal conductivity, wherein, most of the heat transfers due to friction are accumulated over the tool surface. Further, several challenges like increased cutting force, developing high temperature and rapid tool wear are observed during its machining process. To overcome these, the coated tool inserts are used for machining the superalloys. In the present work, the cemented carbide tool is coated with chemical vapor deposition multi-layering Al 2O 3/TiCN under the dry cutting environment. The machining processes are carried out with varying cutting speeds: 65, 81, 95, and 106 m/min, feed rate 0.1 mm/rev, and depth of cut 0.2 mm. The variation in the cutting speeds can attain high temperatures, which may activate built-up-edge development which leads to extensive tool wear. In this context, the detailed chip morphology and its detailed analysis are carried out initially to understand the machining performance. Simultaneously, the surface roughness of the machined surface is studied for a clear understanding of the machining process. The potential tool wear mechanism in terms of abrasion, adhesion, tool chip off, delaminating of coating, flank wear, and crater wear is extensively identified during the processes. From the results, it is observed that the machining process at 81 m/min corresponds to a better machining process in terms of lesser cutting force, lower cutting temperature, better surface finish, and reduced tool wear than the other machining processes.

19

Vibratory Shot Peening of Elements Cut with Abrasive Water Jet

Skoczylas Agnieszka

Advances in Science and Technology. Research Journal

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2022

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Vol. 16, no 2

39--49

EN

The paper presents the effect of technological parameters of vibratory shot peening on the roughness and microhardness of the surface layer of shot peened objects. Moreover, the surface topography results from vibratory shot peening was analyzed. In the experiment, samples made of 1.4301 stainless steel were used, which were cut by abrasive water jet (AWJ). The geometrical structure of the surface after vibratory shot peening was changed. The surface roughness was obtained in the range of Rsk = -0.600 ÷ -1.115 and Sa = 3.01 ÷ 6.53 μm, The value of microhardness ΔHV, near to the surface, is from 36 HV0.05 to 100 HV0.05. The changes in microhardness reach on the depth gh = 100 μm. An analysis of variance ANOVA for the investigated dependent variables was performed. The Tukey's test was used to checked the influence of the independent variable on the dependent variable. The aim to obtain favorable properties of the surface layer of elements after abrasive water jet cutting, it is recommended to use a vibratory shot peening time of approx. 6 minutes and balls of diameter d = 6 mm.

20

Comparative Analysis of the Effect of Machining with Wire and Ceramic Brushes on Selected Properties of the Surface Layer of EN AW-7075 Aluminium Alloy

Matuszak Jakub

Advances in Science and Technology. Research Journal

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2022

|

Vol. 16, no 2

50--56

EN

In the cutting process, when the cutting edge leaves the material, burrs are often formed on the edges of the workpiece. Due to inconveniences associated with burrs, such as problems with properly fixing the workpiece on the machine for further processing or problems with parts working in assemblies, deburring operations must be performed. In addition to that, burrs may pose danger for workers at the production stage and for customers at the stage of using the finished product. One of the popular deburring methods is brushing. Apart from deburring, brushing can be used to change surface layer properties. The aim of this study is a comparative analysis of the effect of machining with wire and ceramic brushes on microhardness and the surface quality of EN AW-7075 aluminium alloy. Results show that, for all defined brushing conditions, lower surface roughness parameters are obtained when using ceramic brushes rather than wire brushes. In contrast, the use of wire brushes leads to increased microhardness of the surface layer.