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employed in the production of aluminium alloys. The essential aim of this research is to examine the deformation mechanisms and discuss the mechanical properties of aluminium during the incremental forming process. The aim was to examine how various process parameters influence the surface properties, hardness, and wear resistance of the workpieces using aluminium alloy type AA6061. The parameters under investigation are increment step down size, feed rate, and spindle rotational speed. Furthermore, the impact of these factors on the forming process was investigated using several methodologies, including the Taguchi method for parameter optimization and surface analysis. The findings of this study demonstrate that spindle rotation speed exerted a substantial influence on both surface roughness and hardness, accounting for 63.41% for hardness and 52.19% for roughness. In terms of wear rate, the step size had the most significant impact, accounting for 48.53%.
100, 200, 400, and 600 kGy using the ILU-10 linear accelerator. Comprehensive analyses were conducted, including thermogravimetric analysis (TGA) to assess thermal stability, X-ray diffraction (XRD) to observe structural changes, and the impact of irradiation on microhardness. Tribological performance was evaluated using the ball-on-disc method. Results indicate that irradiation decreases microhardness by approximately 19% and modifies tribological behavior in a dose-dependent manner. TGA results showed subtle shifts in decomposition onset temperatures, with a reduction of about 10°C post-irradiation, while XRD revealed a 12% decrease in crystallinity, affecting mechanical properties. Further investigations demonstrated that lubrication, particularly under high-load conditions, could enhance PEEK’s operational characteristics post-irradiation. The study underscores the critical role of lubricants in improving the wear resistance and durability of PEEK, making it suitable for high-stress applications in mechanical engineering and manufacturing sectors. The analysis highlights the potential of integrating electron irradiation into existing material processing workflows to improve PEEK's properties, thereby extending its utility across various industrial applications. This approach offers a promising avenue for optimizing the performance and longevity of PEEK components, particularly in environments subject to extreme mechanical stresses.
weldability. Due to all these advantages, it is used in many industry sectors, and the main joining techniques are welding technologies. In this study, two joining techniques were used, SMAW (Shielded Metal Arc Welding) and GTA (Gas Tungsten Arc). The obtained welded joints were subjected to: macroscopic and microscopic metallographic tests, mechanical tests (static bending test and microhardness measurements), diffraction tests, and wear resistance tests. The results showed that the microhardness of the welds is similar and does not depend on the welding method used. In the microstructure of the analyzed joints there are two phases: austenite (γ) and ferrite (δ), with different morphologies depending on the welding conditions, which affect the phase transformations. Material wear within the weld is greater than in the base material.
wszystkim zaletom znajduje zastosowanie w wielu gałęziach przemysłu, a głównymi technikami jej łączenia są technologie spawalnicze. W pracy zastosowano dwie techniki łączenia metodą SMAW (Shielded Metal Arc Welding) i GTA (Gas Tungsten Arc). Uzyskane złącza spawane poddano: badaniom metalograficznym makro- i mikroskopowym, badaniom mechanicznym (statyczna próba zginania i pomiary mikrotwardości), badaniom dyfrakcyjnym oraz badaniom odporności na zużycie. Wyniki badań pokazały, że mikrotwardości spoin są zbliżone i nie zależą od zastosowanej metody spawania. W mikrostrukturze analizowanych złącz występują dwie fazy austenit (γ) i ferryt (δ) o zróżnicowanej morfologii zależnej od warunków spawania, które wpływają na przemiany fazowe. Zużycie materiału w obrębie spoiny jest większe aniżeli w materiale rodzimym.
by selecting L25 orthogonal arrays. The optimum TIG parameters were a welding current of 75 A, an arc potential of 15 V, a welding rate of 120 mm/min, and an argon gas consumption rate of 12 L/min. An ANOVA study found that welding current (46.95%) was the largest contributor in producing the excellent welded joint. The microstructural research indicated increased grain size in the heat-affected zone (HAZ) and fusion zone (FZ), represented by distinct grain boundary layers, intragranulars, and Widmanstätten austenite. This was due to heat input and rapid cooling inclusion as well as re-crystallisation of the ferrite matrix. The elemental mapping analysis showed that chromium must be present to generate a shielding oxide layer, which decreased from 25.50% in the parent material to 23.40% in the TIG welded joint. The tensile test found that TIG welds had an ultimate tensile strength (UTS) of 789 MPa. This value was equivalent to the base metal UTS value of 800 MPa. The micro-hardness test of the TIG welded joint confirmed that the HAZ (350 HV) and FZ (325 HV) were higher than that of the base metal (305 HV). The hardness value near the FZ boundary experienced a significant increase due to the development of hard microscopic components and element migration during the TIG process.
fall height of 220 mm, in order to achieve the clusters fragmentation of hard components, followed by the homogenization annealing at 800°C for 1.5 h. The consolidation technique included solution treatment at 1080°C and aging at 800°C with various holding times. The investigation techniques by X-ray diffraction analysis (XRD) and observations under a scanning electron microscope (SEM) with semi-quantitative analyses (EDS) have offered the possibility to reveal the aluminum addition’s impact and the holding time aging on the material’s microstructural evolution. The sintered alloy with a high Al content (5.25 %) exhibits a complex structure composed of metallic matrix γ, the chromium carbide Cr23 C6 , and a large variety of binary intermetallics. Despite this, the solution treatment caused an almost complete dissolution of these compounds, and consequently, a saturation of the nickel cubic lattice. An increase in precipitation phenomenon was, due to the formation of the intermetallic γ’ (Ni, Co)3 (Al, Ti), and then, the alloyed chromium carbide (Cr, Co, Ni, Mo, Ti)23 C6 , led to a noticeable hardening of the metal matrix, reaching a microhardness of 700 HV0.1.
opadania 220 mm, w celu uzyskania fragmentacji skupień twardych składników, a następnie wyżarzaniu homogenizującym w temp. 800°C przez 1,5 h. Technika konsolidacji obejmowała obróbkę przesycającą w temp. 1080°C i starzenie w temp. 800°C z różnymi czasami przetrzymywania. Techniki badawcze polegające na analizie dyfrakcji promieni rentgenowskich (XRD) i obserwacje pod skaningowym mikroskopem elektronowym (SEM) wraz z analizami półilościowymi (EDS) umożliwiły ujawnienie wpływu dodatku aluminium i czasu utrzymywania starzenia na ewolucję mikrostruktury materiału. Spiekany stop o wysokiej zawartości Al (5,25%) wykazywał złożoną strukturę, na którą składały się: metaliczna osnowa γ, węglik chromu Cr23 C6 i duża różnorodność binarnych związków międzymetalicznych. Mimo to obróbka roztworowa spowodowała niemal całkowite rozpuszczenie tych związków, a w konsekwencji nasycenie sześciennej sieci niklu. Nasilenie zjawiska strącania osadów spowodowane utworzeniem się międzymetalicznego γ' (Ni, Co)3 (Al, Ti), a następnie stopowego węglika chromu (Cr, Co, Ni, Mo, Ti)23 C6 , doprowadziło do zauważalnego utwardzenia osnowy metalicznej, osiągającego mikrotwardość 700 HV0,1.
piston skirts that are used in the cylinder chamber. The primary emphasis of this research is to investigate the accumulative impact that several passes have on Al 6082 surface composites that were filled with graphite nanopowder. The mechanical properties and microstructure of the fabricated composites were studied in order to accomplish this goal. The microstructural investigation showed that the graphite nanopowder particles were evenly distributed throughout the Al-6082 alloy. In addition, better dispersion of the graphite nanopowder was seen throughout the matrix material as the number of passes made during friction stir processing was increased. This may be explained by the reduction in grain size that occurs inside the aluminum metal matrix composites (AMMCs) that are produced as a consequence. According to the results of the research, the microhardness of the material grew to 105.3 HV after the third pass of the tool, and its maximum tensile strength rose to 215±3 MPa. In the ASCs that fabricated after three passes of friction stir processing, the smallest grain size that was measured was 24 micrometers.
weight loss, and wear mechanisms in severe environments. The study aimed to provide an in-depth knowledge of erosion behaviors by analyzing surface characteristics, microstructure characteristics, and material removal mechanisms. The electron probe micro-analyzer studied weld zone element segregation and scanning electron microscopy (SEM) examined microstructure and erosion mechanism. ER2594 filler weld shows higher microhardness as compared to weld fabricated using ERNiCrMo-3 filler metal. Sand particle density, particle-to-surface contact, particle interactions, and fluid impacts increase cumulative weight loss and decrease erosion rate per unit solids weight. Slurry concentration increased weight loss by 23% for sDSS 2507 BM and 33% for IN-625 BM. ER2594-LHI lost 72% and ERNiCrMo-3-LHI 77% more weight with increasing slurry concentration. Filler ERNiCrMo-3 has less erosion wear than filler ER2594 as the concentration of slurry increases. SDSS 2507 BM and IN-625 BM erode 1.45 and 1.8 times faster with increasing slurry concentration, respectively. The erosion rate of ER2594-LHI and ERNiCrMo-3-LHI increases 0.85 and 1.2 times with slurry concentration. SEM analysis of the worn surface exhibits mixed cutting–ploughing modes coexisting with the formation of craters. The material removal has predominantly occurred from the cutting and ploughing mechanism, whereas the characteristic presence of craters and frontal and lateral lips is also found across the entire surface. The results from this study suggest the optimum heat input to be maintained during weld fabrication of sDSS 2507/IN-625 using ER 2594 and ERNiCrMo-3 filler metals for enhanced resistance against slurry erosion wear. Also, an insight into the wear mechanism helps in understanding the effect of microstructural features on the wear performance of welds in operational conditions.
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Charisma Flow) and nanohybrid (Herculite XRV Ultra, Filtek Z550 and Charisma Bulk Flow) composites resin used for dental fillings. Six different composites were used in the study. From each material, 40 cylinder-shaped samples were made. All samples were polymerized and polished using three different methods. To evaluate surface roughness a confocal laser microscope was used, and microhardness was determined using a universal Vickers hardness tester.The data were analysed using the one-way ANOVA test at a significance level of 0.05 for both tests. The smoothest surfaces in all groups of composites were obtained for control samples. Also in all groups of composite samples no statistically significant differences were found between the Sof-Lex and Enhance+PoGo. The measurement of surface roughness obtained for the Kenda system showed significantly lower values than for the other two methods. The surfaces of the control samples showed statistically significantly lower microhardness values compared to all polishing systems for all six tested resin composites, additionally no statistically significant differences were found between all finishing and polishing methods. Regardless of the finishing and polishing method used, the lowest microhardness values among microhybrid materials were found for Charisma Flow, while among nanohybrid materials the lowest values were obtained for Herculite HRV Ultra. Finishing and polishing increases the microhardness of microhybrid and nanohybrid composite resin. The use of Kenda three step polishing system resulted in smoother surface for all tested composite materials compared to the Sof-Lex and Enhance+PoGo systems, while the finishing and polishing method had little effect on the microhardness of the surface.
cast iron EN-GJL 250. Specifically, regular shot peening (RSP) and semi-random shot peening (SRSP) were investigated in the study. The results demonstrated that the surface quality of EN-GJL 250 samples was higher after RSP than after SRSP. The analyzed surface roughness parameters were lower after RSP than after SRSP, with the exception of the Rvk parameter. As a result of RSP, the analyzed roughness parameters increased from 5% to 62% in relation to their values after pre-treatment. The lowest values of the surface roughness parameters were obtained after RSP conduced with the impact energy E = 100 mJ, the distance between the dimples x = 0.3 mm, and the diameter of the shot peening element d = 14.3 mm. Assessment of the 3D surface topography showed significant differences in the formation of machining traces depending on the employed surface treatment. In RSP, the traces were arranged in a uniform manner, with the assumed step, whereas in SRSP the shot peening traces had no set pattern of orientation. The application of RSP and SRSP caused an increase in surface microhardness. The maximum surface microhardness was 75 HV0.5 for RSP and 98 HV0.5 for SRSP. Residual stresses were higher after SRSP than after RSP. Compressive residual stresses were induced in both types of shot peening process.
material. Microhardness of structural components of steels and cast irons (armco iron ferrite, austenitic component of steel 12Х18Н10Т and cementite of centrifugally cast chrome-nickel cast iron (cast coating Ø910 mm)) was determined by restored four-sided pyramid impression with a square base and a top angle of 136±1. The paper evaluates the influence of the main factors on the micro-hardness error of ferritic, austenitic and carbide component of steels and cast irons: the amount and speed of the indenter load, the stiffness of the substrate, the field of distribution of plastic deformations around the impression, the quality of the surface preparation, the influence of grain boundaries and the relaxation of the impression shape over time. The main factors affecting the accuracy of measurements by the reconstructed impression method have been determined for each of the investigated phases: ferrite, austenite, and cementite.
strukturalnych stali i żeliwa (ferryt żelaza armco, austenityczny składnik stali 12Х18Н10Т i cementyt odśrodkowo odlewanego żeliwa chromowo-niklowego (powłoka odlewu Ø910 mm)) określono przez przywrócony wycisk piramidy czterobocznej o podstawie kwadratowej i kącie wierzchołkowym 136±1. W pracy oceniono wpływ głównych czynników na błąd mikrotwardości ferrytycznego, austenitycznego i węglikowego składnika stali i żeliwa: wielkości i prędkości obciążenia wgłębnika, sztywności podłoża, pola rozkładu odkształceń plastycznych wokół wycisku, jakości przygotowania powierzchni, wpływu granic ziaren oraz relaksacji kształtu wycisku w czasie. Określono główne czynniki wpływające na dokładność pomiarów metodą zrekonstruowanego wycisku dla każdej z badanych faz: ferrytu, austenitu i cementytu.
intensities (fixed at 0.01 T, 0.03 T, 0.05 T, 0.1 T, 0.15 T, and 0.2 T and a duration of 5 minutes) and a fixed frequency of 50 Hz. Vickers microhardness and DC% were investigated utilizing the specimens, which were created using circular molds and prepared for compression strength (CS) testing in accordance with ISO 4049. To evaluate DC% before and after MF exposure, Fourier-transform infrared spectroscopy (FTIR/ ATR) was performed. A microhardness tester was used to quantify the samples’ initial VHN while subjecting them to a 500 g load for 15 seconds. After that, properties were evaluated. With the aid of scanning electron microscopy (SEM), the surfaces were evaluated. The one-way analysis of difference and Tukey significant difference tests were used to evaluate the data. Analyses of statistical data showed that DC% tends to rise up to 0.05 T. When compared to the control, VHN and compression strength were considerably decreased after 0.03 T MF (p ≤ 0.05). However, there was a significant difference between the VHN and CS as their values increased with increasing magnetic field intensity. The surfaces of the Vega Ortho were deteriorated, as shown by SEM scans. It was found that the effect of the magnetic field caused changes in the physical and chemical properties.
T, 0,15 T i 0,2 T przez 5 minut) i stałą częstotliwość 50 Hz. Mikrotwardość Vickersa i DC% ustalono z wykorzystaniem próbek, które zostały wykonane przy użyciu okrągłych form i przygotowane do badania wytrzymałości na ściskanie (CS) zgodnie z normą ISO 4049. Do oceny DC% przed ekspozycją na działanie pola magnetycznego i po niej wykorzystano spektroskopię w podczerwieni z transformacją Fouriera (FTIR/ATR). Do ilościowego określenia początkowej wartości VHN próbek użyto mikrotwardościomierza, poddając je obciążeniu 500 g przez 15 sekund. Następnie dokonano oceny właściwości. Ocenę powierzchni przeprowadzono za pomocą skaningowej mikroskopii elektronowej (SEM). Dane poddano jednokierunkowej analizie różnic i testowi istotnej różnicy Tukeya. Analizy danych statystycznych wykazały, że DC% ma tendencję do wzrostu do poziomu 0,05 T. W porównaniu z próbką kontrolną wartości VHN i wytrzymałości na ściskanie uległy znacznemu zmniejszeniu po oddziaływaniu 0,03 T MF (p ≤ 0,05). Istniała jednak znacząca różnica między VHN i CS, ponieważ ich wartości rosły wraz ze wzrostem natężenia pola magnetycznego. Powierzchnie Vega Ortho uległy degradacji, jak wykazały skany SEM. Stwierdzono, że wpływ pola magnetycznego spowodował zmiany właściwości fizykochemicznych.
was used, achieving an effective case depth ECD = 0.5 mm. Subsequently, the cylindrical outer surfaces of the samples were ground by conventional plunge grinding and with innovative kinematics using a test stand based on a conventional flat-surface grinding machine. As part of the study, microhardness and residual stresses were measured before and after grinding. Measurements were carried out to a depth of 1 mm. The main component of the stand is an original special device that allows the cylindrical specimen to be clamped. Then the angle between its axis of rotation and the axis of rotation of the grinding wheel is set with respect to the plane of the grinding machine’s magnetic table. In the described tests, the axis of rotation of the cylindrical specimen was deviated from its original position by 15° and set at an angle of 75° to the axis of rotation of the grinding wheel. The specimens were ground with a grinding wheel of noble electro-corundum marked 38A60K8V. In both kinematic cases of the grinding process, a machining allowance of 0.01 mm was removed. Findings: Grinding using innovative kinematics did not cause any significant changes in the microhardness distribution, either for vacuum or conventional carburizing. In addition, residual stress measurements using the Dawidenkov-Sachs method showed that innovative grinding enables a more favourable distribution than those obtained after conventional plunge grinding. Research limitations/implications: Further research will focus on, among others, selecting the angular settings of the workpiece axes relative to the grinding wheel axes depending on their dimensions. Grinding guidelines should include coverage ratio, infeed value, grinding time, and peripheral speeds. In addition, the plan for future research includes measuring the components of the grinding force and the geometric structure of the surface. Practical implications: Grinding process is a crucial stage of steel treatment in almost every industrial branch. In sustainable manufacturing, it is extremely important to produce high-quality items while reducing the cost of manufacturing and taking care of the environment and workers’ health. Originality/value: The proposed test stand, together with the authors’ device, makes it possible to conduct machining of the external surfaces of cylindrical workpieces on a flat surface grinder. In this case, the innovation of the grinding process consists of the non-parallel alignment of the cylindrical rotational axis of the specimen and the rotational axis of the grinding wheel with respect to the plane of the magnetic grinding table.
infiltracji, pomiar wytrzymałości na statyczne zginanie zębów, pomiar mikrotwardości kół zębatych oraz analizę ich mikrostruktury. Koła zębate podzielono na cztery grupy; jedna z nich nie była infiltrowana miedzią, pozostałe trzy infiltrowano kolejno jednym (1,4% Cu), dwoma (2,8% Cu) i trzema (4,2% Cu) miedzianymi pierścieniami. Stwierdzono, że infiltracja miedzią powoduje wzrost wytrzymałości na zginanie badanych spieków, lecz tylko w przypadku zawartości 1,4% Cu. Większa ilość miedzi powoduje obniżenie wytrzymałości na zginanie zębów kół. Badania wykazały również, że infiltracja miedzią nie wpływa korzystnie na mikrotwardość kół zębatych.
determination of changes in the dimensions of the gear wheels and their density, before and after the infiltration process, measurement of the strength to static bending, measurement of the microhardness of the gear wheels and analysis of their microstructure. The gear wheels are divided into four groups; one of them was not infiltrated with copper, the remaining three were infiltrated successively with one (1.4% Cu), two (2.8% Cu) and three (4.2% Cu) copper rings. It was found that copper infiltration increases the bending strength of the tested sinters, but only in the case of 1.4% Cu content. The greater amount of copper reduces the bending strength of the gear wheels. Research has also shown that copper infiltration does not have a positive effect on the microhardness of gear wheels.
of this study was to investigate the mechanical properties and physical characteristics of a stir cast hybrid aluminium nanocomposite reinforced with 1-3 wt.% cerium oxide (CeO2) and graphene nanoplatelets (GNPs). Utilizing SEM, microstructural analysis was carried out. The existence of the elements of the reinforcement in the manufactured nanocomposite specimens was verified using EDAX. With an increase in the reinforcement wt.%, improvements in the mechanical and physical properties were seen. In the hybrid nanocomposites reinforced with 3 wt.% GNPs and 3 wt.% CeO2, a low porosity of 1.06% was observed. The best results for tensile strength, yield strength, and microhardness were 398 MPa, 247 MPa, and 119.6 HV, respectively. The SEM micrographs of the studied materials showed that the reinforcement particles were uniformly dispersed and refined into ultrafine grains.
Ti6Al4V ELI as filler metal was characterized using the microstructure, microhardness, and tensile strength. The joint was classified into three regions, namely, fusion zone (FZ), heat affected zone (HAZ), and base metal (BM). Results show martensitic microstructure within the fusion zone (FZ) and the heat affected zone (HAZ), which resulted in an increased hardness within the fusion and heat affected zone.
Microstructure analysis included scanning electron microscopy and energy dispersive X-ray spectroscopy techniques. The studies revealed the presence of multi-phase structures in both alloys. Elemental distribution maps confirmed the presence of all six alloying elements in the microstructure. The segregation of chemical elements was also observed. Microhardness measurement revealed that both alloys exhibited microhardness from 832(27) to 933(22) HV1.
as the kinetic parameters of the nitrided layer’s growth. The activation energy for the formation of a nitride layer is ~108 kJ/mol. The authors discuss the morphology of the nitride layers as well as their roughness and surface hardness. The study determines the effective diffusion coefficient for the growth of diffusion layers in the temperature range of 750...850°C: Def = D0 × exp (-E/RT), where D0 = 0.0177 m2/s; E = 215.7 kJ/mol. The friction coefficient of the disk from nearbeta-titanium alloy with a bronze block is lowered by significantly more than 10 times after gas nitriding, and the temperature in the friction zone is reduced by 2.5 times.
about 0.8, but their average powder sizes differed respectively at approximately 11 µm and 5 µm. From XRD results, only the peaks of pure Ti, Al and Nd were detected in both powders. The obtained Ti-Al-Nd powders were consolidated by SPS technique at 1373 K for 15 min under a pressure of 50 MPa in vacuum, resulting in high density over 99%. EDS and XRD analyses indicated the formation of binary phases such as TiAl3, TiAl, Ti3Al5, and NdAl3 after SPS in both cases of STS and zirconia balls, while the ternary Ti-Al-Nd phase was detected only in the case of zirconia balls. The size of second phases was slightly smaller in the case of zirconia balls. The microhardness of the sample was 790 Hv with zirconia balls and 540 Hv with STS balls.
thickness, chemical composition and properties. When pulled through the drawing die the zinc coating heats up (as a result of friction between the material and the tool) and its dynamic plastic deformation. It resulted in the fracture and partial crushing of the hard-intermetallic phases. It has been proven that as the wire passes through successive drawing dies, the coating is thinned and diffusion as well as phase remodelling of individual structural components occurs; in the place of phase ζ, the intermetallic phase δ1 develops, increasing its share in the diffusion layer. The crystals of intermetallic phases located on the border of the diffusion and outer layers break up and remain dispersed in the zinc. An analysis of the microhardness of the coating has proven that the level of the increase in the microhardness of the zinc coating is contingent on percentage of iron in particular layers of coating.
into nine environments (artificial saliva – AS, deionized water and 0.9% NaCl) differing in composition of the solution and pH was determined. Six samples were prepared for each solution. In the short-term study, the measurements were taken after 1, 3, 24, 48, 72 and 168 hours. The cumulative values as well as levels of fluoride ions released at concrete time intervals were compared. Within 7 days (168 hours), both materials showed variable levels of fluoride ions release. The highest value of fluoride ions release from nanohybrid Tetric EvoCeram material was reported in deionized water (8) after 24 hours (1.550 ± 0.014 [µg/mm2 /h]) and the lowest value was read in the artificial saliva AS pH 7.5 (5) after 1 hour (0.022 ± 0.001 [µg/mm2 /h]). What’s more, the highest value of Frelease from Vitremer was found in deionized water (8) after 168 hours of immersion (24.021 ± 2.280 [µg/mm2 /h]) and the lowest value was in the artificial saliva AS (without Ca2+) pH 4.5 (6) (0.303 ± 0.249 [µg/mm2 /h]) after 168 hours. Cumulated release of F– after 7 days was notably higher from resin- modified glass ionomer material – Vitremer in all artificial saliva solutions (1–7) which imitated the environment of oral cavity. Therefore, we can assume that Vitremer has better remineralization potential and it may constitute a more effective method of tooth decay prevention.
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