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1

The influence of technological parameters of plasma cutting on the quality and surface roughness when cutting thick steel sheets

Góral Tomasz, Dzienniak Damian

Mining Machines

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2024

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vol. 42, iss. 2

108--118

EN

The purpose of this study was to analyze the effect of selected parameters on the quality of plasma cutting. The main parameter studied was the cutting speed and how it affects the roughness of the cut surface. The second parameter analyzed was the currentintensity adjusted depending on the thickness of the material being cut, which also has a significant effect on the surface quality of the metal being cut. The evaluation of the quality of the cut surface was carried out on 8, 20, 30 and 35 mm thick sheets of S235JR grade steel. Several samples were selected from each thickness for measurement and testing. The samples were cut with a MAGNUM CUT 160 plasma cutter. The results show that the current intensity and the speed of the torch pass have a significanteffect on the quality of the cut surface.

2

Surface roughness prediction and roughness reliability evaluation of CNC milling based on surface topography simulation

Zhang Ziling, Lv Xiaodong, Qi Baobao, Qi Yin, Zhang Milu, Tao Zhiqiang

Eksploatacja i Niezawodność

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2024

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Vol. 26, no. 2

art. no. 183558

EN

Surface roughness is influenced by various factors with uncertainty characteristic, and roughness reliability can be used for the assessment of the surface quality of CNC milling. The paper develops a method for the assessment of surface quality by considering the coupling effect and uncertainty characteristicsof various factors. According to the milling kinematics theory, the milling surface topography simulation is conducted by discretizing the cutting edge, machining time, and workpiece. Considering thecoupling effect of various factors, a roughness prediction model isestablished by the SSA-LSSVM, and its prediction accuracy reachesmore than 95%. Then, the roughness reliability model isdevelopedby applying the response surface methodology to achieve the assessment of surface quality. The proposed method is verified by the milling experiments. The maximum values of the relative errors between the simulation and experimental results of the surfaceroughness and roughness reliability are 9% and 1.5% respectively, indicating the correctness of the method proposed in the paper.

3

Experimental investigation and machining analysis of Mg/TiC composites during EDM

Dash Dharmeswar, Devarajaiah Devarasiddappa, Dash Santosh Kumar, Samanta Sutanu, Rai Ram Naresh

Composites Theory and Practice

|

2024

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R. 24, nr 1

9--16

EN

Electrical discharge machining (EDM) is one of the prominent non-conventional machining processes used to machine metal matrix composites. Mg/TiC composites are found in many industrial applications and conventional machining of the same is highly challenging. This paper aims to study the machinability analysis of Mg/TiC composites using EDM with pulseon time (Ton), pulse-off time (Toff) and input current (I) as the process variables with the material removal rate (MRR) and surface roughness (SR) as the performance measures. Stir cast Mg-alloy reinforced with TiC (0, 5, 10, 15 and 20) by weight was used as the workpiece. The EDM experiments were conducted as per L25 orthogonal array (OA) and the results were analyzed to study the effect of the process variables on MRR and SR. The parametric study showed that SR increases linearly with Ton and is attributed to larger craters produced at a higher pulse energy. MRR was also observed to grows with the rise in Ton as more material melts due to high-intensity pulses. As per the ANOVA results, Ton was found to be the most influential process variable affecting SR and MRR with a 79% and 34% contribution, respectively. Surface morphology investigations using SEM micrographs revealed the presence of globules and sphere-shaped metal deposits and were found responsible for increased SR.

4

Evaluation of selected properties and surface quality of cured pre-impregnated carbon-fiber fabrics after exposure to sulphuric acid

Kojnoková Tatiana, Nový František, Markovičová Lenka, Harea Evgheni, Harea Evghenii

Production Engineering Archives

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2023

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Vol. 29, Iss. 1

1--6

EN

This paper deals with changes in selected properties of composite material and surface degradation after exposure to an acidic environment. A carbon fiber-reinforced composite (CFRP) produced from prepregs was tested. The weight change, micro-hardness, and surface degradation of the CFRP composite made of cured pre-impregnated laminates were evaluated in this study. Material consisting of a DT121R epoxy resin matrix with high reactivity and high viscosity, with two reinforcing carbon fabrics layers, is characterized by a low value of tensile strength. Evaluation of changes in the material properties was performed before and after exposure to specific environmental conditions, which are achieved by using a chemical solution of 15% H2SO4 at various temperatures. Subsequently, the effect of 15% H2SO4 at various temperatures on the material properties was monitored. The specimens were immersed in the solution for up to 3 and 6 weeks at the temperatures of 23°C, 40°C, and 60°C. It was found out, that the degradation of the composite material is conditioned by the aging of the epoxy resin (matrix). Carbon fibers (reinforcement) are relatively stable. The weight change, micro-hardness, and surface quality depend on the time of exposure to acidic solution and temperature. The micro-hardness tests show a significant influence on exposure time. The biggest changes in weight change and surface quality of the CFRP composite were observed after exposure at the temperature of 60°C.

5

New trends in hybrid finishing processes of metallic additively fabricated parts – a short review

Rech Joel, Grzesik Wit

Journal of Machine Engineering

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2023

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Vol. 23, No. 1

36--46

EN

This comprehensive survey highlights some important finishing processes used in fabricating additively manufactured parts, mainly using SLM (Selective Laser Melting). In practice, there are applied hybrid processes which integrate additive and subtractive componential processes (AM+SM type) or additional finishing processes, mainly based on the electrochemical polishing such as ECP (Electrochemical Cavitation Polishing) and PEMEC (Electrochemical-Mechanical Polishing) ones. On the other hand, AFM (Abrasive Flow Machining) is predominantly recommended for conformal cooling (CC) channels. Some conclusions and future trends in the implementation of special hybrid finishing processes are outlined.

6

Experimental Research on the Influence of Roughness of the Machined Surface of a Part on Galvanization

Ravai Nagy Sandor, Pop Alina Bianca, Nabiałek Marcin, Alexandru Costin, Țîțu Aurel Mihail

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 4

1591--1595

EN

The purpose of this scientific paper is to follow the influence of thermal galvanizing, as a technological process on the quality of the galvanized surface. The galvanizing technology used and studied involves at the end of the process, the removal of excess zinc from the surface by centrifugation. The zinc layer will be lower than that of simple immersion galvanizing. The measurements were performed following the roughness of the machined surface on a five-Section specimen - each Section being processed with a different cutting regime. The results were analyzed after each operation. The first measurements were made after the turning operation, followed by measurements made after pickling and fluxing and then after thermal galvanizing. Based on the results obtained, the aim was to set up a range of best roughness at which the galvanized part should have a commercial appearance and be made with a cost-effective cutting regime in terms of costs.

7

Effects of EDM on the Chemical Composition and Microstructure of the Surface Layer of Alnico Alloys

Bańkowski Damian, Młynarczyk Piotr, Szwed Bartłomiej

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 2

106--111

EN

This article deals with the effects of electrical discharge machining (EDM) on the chemical composition and microstructure of cast Alnico alloys, i.e., iron-based alloys composed of aluminum, nickel and cobalt. The experiments focused on determining the chemical composition of the surface layer before and after the EDM process. The microstructure of the material altered by the EDM was also examined. The study included measurement of the thickness of the white layer characteristic of EDM. It is evident that low values of the surface roughness parameters can be obtained by correctly selecting the EDM process parameters. The average surface roughness reported in the experiments was 1 μm. The surface roughness measurements were conducted with a Talysurf CCI lite non-contact profiler. The metrological results also indicate that lower surface roughness can be obtained at small discharge energies.

8

Initial assessment of the quality of road surfaces

Szczucka-Lasota Bożena, Waligóra Kamil, Węgrzyn Tomasz, Wszołek Łukasz

Zeszyty Naukowe. Organizacja i Zarządzanie / Politechnika Śląska

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2022

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z. 157

571--578

EN

Purpose: The aim of the article is to check the quality of the road and classify the selected road on a four-level scale. Design/methodology/approach: The paper outlines the impact of comprehensive road surface quality management on the safety of vehicles and road users. The basic types of road damage were presented, as well as preliminary diagnostics of a randomly selected national road was carried out. Visual tests were carried out to determine: the type and geometry of the pavement damage, the number of damage, the area covered by the damage. In the article the damage indicators were calculated. The results allowed for the assessment of the quality of the tested pavement and its classification on a four-point scale. Findings: The quality of the road surface was assessed and classified as level C. Research limitations/implications: In the future, it can be suggested to change the methodology of investigate the road. It is proposal to using drone with the application. Practical implications: The research indicates the need to plan the renovation of the road surface and suggests changing the surface material from construction asphalt to the new modified asphalt. Originality/value: The article indicates the need to amend the documents and the current methodology of the procedure.

9

Zgrzewanie oporowe w praktyce inżynierskiej

Lonkwic Paweł, Usydus Ireneusz

Obróbka Metalu

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2022

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nr 2

47--53

PL

Zgrzewanie oporowe, zarówno punktowe jak i liniowe wykorzystywane jest w wielu branżach. Z uwagi na krótki czas operacji obserwuje się szybki wzrostu liczby produkowanych detali tą technologią łączenia. Można ją stosować do łączenia materiałów, tzw. jednoimiennych oraz dwuimiennych (blach o różnych grubościach). W artykule przedstawiono analizę informacji literaturowych oraz rezultaty badań eksperymentalnych z tego zakresu, na podstawie których wskazano czynniki determinujące jakość połączeń wykonanych tą technologią.

EN

Point and linear resistance welding are used in many industries. Due to the short operating time, a rapid increase in the number of parts can be observed with this connection technology. It can be used to connect so-called one-name and two-name materials (sheets with different thicknesses).In this paper analyses literature information and experimental investigations on this domain were consisted. On the basis of experiments factors determining the quality of connections with this technology were identified. resistance welding, surface quality, connection strength.

10

Czynniki determinujące jakość powierzchni po frezotoczeniu

Słomion Małgorzata, Wojciechowski Andrzej, Matuszewski Maciej, Polishchuk Oleg

Obróbka Metalu

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2022

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nr 3

40--44

PL

W artykule przedstawiono technologię frezotoczenia. W szczególności scharakteryzowano uwarunkowania technologiczne determinujące jakość powierzchni po obróbce. Uwypuklono najważniejsze zalety i wady frezotoczenia.

EN

In this paper the technology of turn-milling is presented. In particular, the technological conditions determining the quality of the surface after treatment were characterized. The most important advantages and disadvantages of turn-milling are described too.

11

Finishing processes of additively manufactured metallic parts

Grzesik Wit, Rech Joël

Mechanik

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2022

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R. 95, nr 10

33--37

EN

This review paper highlights some important finishing processes used in fabricating additively manufactured metalic parts, mainly using SLM (selective laser melting). In practice, there are applied hybrid processes which integrate additive and subtractive componential processes (AM + SM type) or additional finishing processes, mainly based on the electrochemical polishing such as ECP (electrochemical cavitation polishing) and PEMEC (electrochemical-mechanical polishing) ones. For conformal cooling (CC) channels AFM (abrasive flow machining) is predominantly recommended. Some conclusions and future trends in the implementation of hybrid processes are outlined.

PL

W artykule dokonano przeglądu procesów wykańczającego kształtowania złożonych wyrobów metalowych wytwarzanych techniką przyrostową, głównie poprzez selektywne topienie laserowe (SLM). W praktyce stosuje się kombinację kształtowania przyrostowego i ubytkowego (AM + SM) lub dodatkową obróbkę wykańczającą złożonych geometrycznie wyrobów z użyciem procesów konwencjonalnych i hybrydowych w celu uzyskania żądanych jakości powierzchni i właściwości użytkowych, m.in. przetłaczanie ścierne (AFM) do wykańczania powierzchni zewnętrznych oraz polerowanie elektrochemiczne wspomagane ultradźwiękami (ECP) i polerowanie elektrochemiczno-mechaniczne (PEMEC) do wykańczania konforemnych układów chłodzących.

12

Technological methods of ensuring the reliability of lock connections in marine gas turbines

Dvirna Olha, Zembrzuska Natasza

Journal of KONBiN

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2022

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Vol. 52, iss. 3

149--163

EN

The article presents the test results of the surface quality parameters after broaching of heat-resistant steels of grades: 1.7335 (13CrMo4-5) and 1.4841 (X15CrNiSi25-20). The aim of the work is to determine the technological methods of obtaining the lowest treated surface roughness, surface layer hardening and the elimination of surface defects after broaching. To investigate the influence of cutting conditions (cutting speed, tool geometry and feed) on surface roughness and hardness, the physical modeling method of the broaching was used. As a result of the research, recommendations for improvement of the main parameters of the surface layer quality when broaching samples from selected grades of heat-resistant steels.

PL

W artykule przedstawiono wyniki badań parametrów jakości powierzchni po przeciąganiu stali żaroodpornych gatunków: 1.7335 (13CrMo4-5) i 1.4841 (X15CrNiSi25-20). Celem pracy jest określenie technologicznych sposobów uzyskania najmniejszej chropowatości obrobionej powierzchni, korzystnego poziomu umocnienia warstwy wierzchniej i eliminacji defektów powierzchniowych po obróbce skrawaniem. Aby zbadać wpływ warunków skrawania (prędkości skrawania, geometrii narzędzia i prędkości posuwu) na chropowatość i umocnienia powierzchni, zastosowana została metoda modelowania fizycznego procesu przeciągania. W wyniku badań opracowane zostały rekomendacje dotyczące podniesienia głównych parametrów jakości warstwy wierzchniej podczas przeciągania próbek z wybranych gatunków materiałów żaroodpornych.

13

Ocena jakości ściany wykonanej w technologii druku 3D za pomocą systemu analizy obrazu

Skibicki Szymon

Inżynieria i Budownictwo

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2022

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R. 78, nr 3-4

124--127

PL

W artykule przedstawiono pilotażowe badania dotyczące zastosowania systemu analizy obrazu do oceny jakości struktur wykonanych w technologii druku 3D kompozytów cementowych. Zaproponowany algorytm w sposób prawidłowy ocenia jakość powierzchni wydrukowanych elementów. Analiza nieciągłości mieszanki tą metodą może być przydatna nie tylko w ocenie estetyki wykonanych elementów, ale także możliwe jest jej powiązanie z właściwościami mechanicznymi, skurczem oraz trwałością drukowanej struktury.

EN

The paper presents a pilot study on the use of an image analysis system to assess the quality of structures made in the 3D printing technology of cementitious composites. The proposed algorithm correctly evaluated the surface quality of the printed elements. Analysis of the path discontinuity with this method can be useful not only in the assessment of the aesthetics of the manufactured elements, but also it is possible to link it with the mechanical properties, shrinkage and durability of the printed structure.

14

Analysis of surface quality after oxygen cutting

Krawczyk Ryszard, Słania Jacek

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2022

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Vol. 66, No. 2

33--41

EN

The article discusses tests concerning surface quality after the oxygen cutting of steel plates of various thicknesses. The study involved visual tests, macro and microscopic metallographic tests as well as hardness measurements and the identification of hardness distribution in the cut zone and in the heat affected zone.

PL

Przedstawiono badania jakości powierzchni po cięciu tlenowym blach stalowych o różnej grubości. Przeprowadzono ocenę wizualną powierzchni próbek po cięciu tlenowym oraz wykonano badania makro- i mikroskopowe zgładów poprzecznych pobranych z próbek. Wykonano pomiary twardości i przedstawiono ich rozkład w strefie cięcia, a także w strefie wpływu ciepła.

15

Machinability Studies on the Turning of Magnesium Metal Matrix Composites

Gobivel K., Vijay Sekar K.S.

Archives of Metallurgy and Materials

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2022

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Vol. 67, iss. 3

939--948

EN

Magnesium-based MMCs are widely used in structural-based applications due to their lightweight, high hardness, corrosion and wear resistance. Also, machining is an important manufacturing process that is necessary to ensure dimensional accuracy and produce intricate shapes. In this context, the machining of Magnesium based metal matrix composites is undertaken to study the impact of the cutting parameters on the machinability behaviour. In this work, turning of pure Mg/SiCp on a Lathe is done and an in-depth assessment on the machining forces, machined surface quality, chip microstructure, and tool morphology has been carried out using TiAlN coated tooling insert. The analysis revealed that the thrust force decreased due to the thermal softening of the matrix meanwhile the feed force also followed the similar trend at higher cutting speeds because of the minimized built-up edge and cutting depth whereas principal cutting force was inconsistent at higher cutting speeds. The surface finish was better at high cutting speed - low feed combination. The chip microstructure revealed that gross fracture propagation at the free surface and variations in the shear bands have occurred at different cutting speeds. Tool studies using SEM analysis revealed wear modes like chipping and built-up edge at low cutting speeds, but with a reduced impact at intermediate cutting conditions, whereas abrasion wear was observed predominantly in the tool nose at higher cutting speeds.

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

The Effect of Reclaim Primary Quality on Moulding Sand Parameters and Quality of Ductile Iron Casting Surface Layer

Kamińska Jadwiga, Angrecki M., Puzio S., Stachowicz M.

Archives of Foundry Engineering

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2022

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Vol. 22, iss. 2

83--88

EN

The aim of the research was to determine the effect of the primary quality of reclaim from dry mechanical reclamation on the strength properties and service life of moulding sands based on this reclaim. Another aim was to establish the effect of the quality of reclaim, sulphur content - in particular, on the surface quality and thickness of the deformed surface layer in ductile iron castings. The research has revealed differences in the strength parameters and service life (mouldability) of sands based on the tested reclaims, depending on the type of the furfuryl resin used, including resins whose synthesis was done as part of the Żywfur project. Examinations of the structure of the surface layer of test castings poured in moulds made of loose self-hardening sands containing the addition of reclaim have confirmed the occurrence of degenerated spheroidal graphite in this part of the casting. It should be noted here that when massive castings with a long solidification time are made, the graphite degeneration effect can be more visible and the layer with the changed structure can increase in thickness. The research has clearly shown that it is necessary to control the parameters of the reclaim, including sulphur content which is transferred from the hardener and accumulates on the grains. This phenomenon has a negative impact not only on the sand strength and technological properties but also on the surface layer of castings.

18

Effects of weathering on mechanical properties and surface roughness of Endospermum malaccense wood modified with propionic anhydride

Uyup Mohd Khairun Anwar, Lee Seng Hua, Husain Hamdan, Siam Nordahlia Abdullah, Jasmani Latifah

Drewno : prace naukowe, doniesienia, komunikaty

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2021

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vol. 64, nr 207

101--110

EN

This study evaluated some properties of sesenduk (Endospermum malaccense) wood treated with propionic anhydride and exposed to outdoor conditions for up to one year. Defect-free samples of sesenduk were extracted with a 3:1:1 (v/v) mixture of toluene, ethanol and acetone for 3 hours at a temperature of 100°C. The samples were then modified at the same temperature for another 3 hours using propionic anhydride and 10% sodium formate as catalyst. Modulus of elasticity (MOE), modulus of rupture (MOR) and parallel-to-grain compression strength of the samples exposed to weathering were tested. Chemical treatment reduced the MOE but slightly increased the MOR and parallel-to-grain compression strength compared with untreated samples. However, treated samples retained higher strength properties than untreated ones. The modulus of elasticity, modulus of rupture and parallel-to-grain compression strength of treated samples at radial orientation were respectively 20%, 31% and 62% higher than those of untreated samples after one year’s outdoor exposure. Weathering adversely influenced the surface quality of the specimens for all exposure times.

19

Surface texture analysis of the X5CrNi18-10 steel after cutting with abrasive water jet and photon beam (laser)

Romanowski Marcin, Nadolny Krzysztof

Journal of Mechanical and Energy Engineering

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2020

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Vol. 4, No 4

365--374

EN

The article presents an analysis of the geometric structure of the surface of X5CrNi18-10 steel sheet after cutting with a abrasive water-jet (AWJ) and a photon beam (laser). Both methods and the workpiece material were also described. Using the laser triangulation method, the cut surface texture was measured by opto-digital microscopy. Additionally, microscopic images of the cut surface were made using the Dino-Lite Edge AM7915MZT microscope by ANMO Electronics Co. The analysis of changes in the value of the Sa parameter for the surface after laser cutting and abrasive water-jet showed that the thickness of the cut material has the most significant influence on the obtained measurement results.

20

Effect of cutting parameters and machining environments on the chips characteristics and surface quality of commercial high-conductive materials

Kaiser Mohammad Salim, Rahman Khandaker Tawshif, Ahmed Sheikh Reaz

Journal of Mechanical and Energy Engineering

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2020

|

Vol. 4, No 4

325--334

EN

The present paper is on the physical and mechanical characterization of machined chips of commercially available highly conductive materials, namely aluminium and copper under different machining environments. More specifically, geometry and hardness of chips as well as the chips removal effect on the machined surfaces are investigated in a quantitative fashion as a function of machining fluid and cutting parameter. The machining is carried out using a horizontal shaper machine with a V-shaped HSS tool under three different machining fluids, where the feed rate is kept constant, while the cutting speed and depth of cut are varied. Results show that chips attain the lower hardness in dry machining conditions than those of under kerosene and soluble oil as a phenomenon alike to hot rolling. Discontinuous chips are formed at low depth of cut for Al and higher depth of cut for Cu in dry condition. Cutting fluid offer improved surface quality through less friction and built up edge formation. Cu generates more heat than Al since copper is harder than aluminum and cutting speed is more effective than depth of cut.