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1

Współczesne technologie wytwarzania w przemyśle lotniczym. Cz. II

Józwik Jerzy

Stal, Metale & Nowe Technologie

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2023

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nr 3-4

40--49

PL

W artykule przedstawiono i omówiono wybrane technologie wytwarzania stosowane w przemyśle lotniczym. Skupiono się na technologiach obróbki ubytkowej, szczególnie w przypadku kształtowania części konstrukcji statków powietrznych.

2

Wpływ obróbki kriogenicznej i cieplno-chemicznej na poprawę trwałości eksploatacyjnej matrycy prasy do wyciskania metodą KOBO

Gołębiewska-Kurzawska J., Wiśniewski K., Juszczyk B., Kulasa J., Marszowski K., Kalabis J.

Rudy i Metale Nieżelazne Recykling

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2018

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R. 63, nr 10

8--14

PL

Celem niniejszej pracy była analiza możliwości poprawy trwałości eksploatacyjnej matrycy prasy do wyciskania metodą KOBO poprzez łączne zastosowanie różnych wariantów zabiegów obróbki kriogenicznej i cieplno-chemicznej. W pracy analizowano i oceniono ich wpływ na poprawę twardości i zużycie tribologiczne materiału matryc w testach twardości, udarności i tribologicznych. Rozwiązania (warianty obróbcze) zostały przetestowane na matrycach w warunkach rzeczywistej pracy.

EN

The aim of the present study was to analyse the possibility of improving the exploitation durability of die for KOBO extrusion process by using a combination of cryogenic and thermo-chemical treatments. The study analyzed and evaluated their influence on the improvement of hardness and tribological wear of dies material. The solutions (machining variants) have been tested on the matrices in real-life conditions..

3

Hybrydowe procesy skrawania wspomagane mediami technologicznymi

Grzesik W.

Mechanik

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2018

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R. 91, nr 12

1050--1056

PL

Przedstawiono hybrydowe sposoby skrawania, wykorzystujące wspomaganie mediami technologicznymi (media-assisted machining – MAM). Omówiono zasady i możliwości technologiczne intensywnego chłodzenia CCS pod dużym ciśnieniem (high pressure cutting – HPC), minimalnego chłodzenia (minimum quantity cooling/lubrication – MQC/MQL), chłodzenia kriogenicznego (cryogenic machining – CM) oraz integracji tych oddziaływań w procesie skrawania w różnych zastosowaniach przemysłowych – zwłaszcza w przypadku kształtowania elementów z materiałów trudnoskrawalnych. Opisano sposoby zasilania mediami technologicznymi oraz rozwiązania narzędzi/systemów narzędziowych i wyposażenie obrabiarek hybrydowych CNC. Podano przykład optymalizacji obróbki MAM z uwzględnieniem chłodzenia kriogenicznego.

EN

A special group of hybrid assisted processes termed media-assisted processes which various liquid and gaseous media supplied to the cutting zone is highlighted. Special attention is paid on such cooling techniques as high-pressure machining (HPC), high-pressure jet assisted machining (HPJAM), minimum quantity cooling/lubrication (MQC/MQL) and a group of cryogenically cooled machining including such cryogenic media as CO2 snow and liquid nitrogen (LN2). Some important effects resulting from the various cooling strategies are outlined and compared. In particular, quantitative effects concerning chip breaking, thermal and tribological behavior of the cutting process as well as burr reduction, surface quality and subsurface layer are presented. The optimization procedure concerning both energy consumption and machining costs in terms of material removal rate (MRR) is presented.

4

The influence of cooling techniques on cutting forces and surface roughness during cryogenic machining of titanium alloys

Wstawska I., Ślimak K.

Archives of Mechanical Technology and Materials

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2016

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Vol. 36

12--17

EN

Titanium alloys are one of the materials extensively used in the aerospace industry due to its excellent properties of high specific strength and corrosion resistance. On the other hand, they also present problems wherein titanium alloys are extremely difficult materials to machine. In addition, the cost associated with titanium machining is also high due to lower cutting velocities and shorter tool life. The main objective of this work is a comparison of different cooling techniques during cryogenic machining of titanium alloys. The analysis revealed that applied cooling technique has a significant influence on cutting force and surface roughness (Ra parameter) values. Furthermore, in all cases observed a positive influence of cryogenic machining on selected aspects after turning and milling of titanium alloys. This work can be also the starting point to the further research, related to the analysis of cutting forces and surface roughness during cryogenic machining of titanium alloys.

5

Experimental Investigation Of Segregation Of Carbon Atoms Due To Sub-Zero Cryogenic Treatment In Cold Work Tool Steel By Mechanical Spectroscopy And Atom Probe Tomography

Min N., Li H. M., Xie C., Wu X. C.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 2A

1109--1113

EN

In this work, we present mechanical spectroscopy of cold work tool steel subjected to sub-zero cryogenic soaking treatment to reveal the carbon segregation and the subsequent carbides refinement. The maximum of Snoek-Köster (SK) peak height was obtained in the sample subjected to soaking 1h at −130°C cryogenic treatment. The SK peak height is reduced with prolonging the soaking time. The results indicate that an increase in the height of SK peak is connected with an increase in dislocation density and the number of segregated carbon atoms in the vicinity of dislocations or twin planes after martensite transformation at −130°C which is confirmed by corresponding TEM and atom probe tomography measurement. Hence, it is suggested that the isothermal martensite, formed during the cryogenic soaking treatment decreases (APT) the height of SK peak.

PL

W pracy przedstawiono wyniki spektroskopii mechanicznej stali narzędziowej do pracy na zimno poddanej obróbce kriogenicznej w celu odsłonięcia segregacji węgla i późniejszego tworzenia węglików. Dzięki połączeniu transmisyjnej mikroskopii elektronowej (TEM) i tomografii atomowej (APT) uzyskano maksymalny pik Snoek-Köstera (SK) w próbce poddanej obróbce kriogenicznej przez 1 godzinę w −130°C. Wysokość piku SK obniża się wraz z wydłużeniem czasu obróbki. Wyniki wskazują, że zwiększenie wysokości piku SK jest połączone ze wzrostem gęstości dyslokacji i liczby segregowanych atomów węgla w sąsiedztwie dyslokacji lub płaszczyzn bliźniaczych po przemianie martenzytycznej w -130°C, co potwierdzone jest odpowiednimi pomiarami TEM oraz APT. W związku z tym proponuje się, że izotermiczny martenzyt powstały podczas obróbki kriogenicznej zmniejsza wysokość piku SK.

6

Cryogenic machining, surface integrity and machining performance

Kopac J., Krolczyk G.

Archives of Materials Science and Engineering

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2015

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Vol. 71, nr 2

83--93

EN

Purpose: Of this paper is to present state-of-the-art on cryogenic machining and delivery principles of liquid nitrogen to the machining/cutting zone. Additionally, the influence of cooling/lubrication conditions on the surface integrity, generated during turning of Inconel 718, are analysed and presented. Design/methodology/approach: Of the paper are to present the design of the cryogenic machining system and how the liquefied nitrogen is delivered to the cutting zone. Additionally, the system is used to evaluate the effect on surface integrity of machined Inconel 718 workpiece. Methodologies used for the surface integrity evaluation are: electro-polishing, X-ray diffraction and micro indentation hardness measurements, with the approach to evaluate the extent of cryogenic influence on machined surface. Findings: The results show that the cryogenic machining process generates larger compressive residual stresses, and prevail at deeper levels beneath the machined surface, thus resulting in improved product quality and performance characteristics in terms of fatigue life and wear resistance. Research limitations/implications: The solutions of the delivery and the evaluation results have been all performed for the turning process, while there is still a challenge for the implementation of findings on the milling and drilling process kinematics. Practical implications: Work shows that cryogenic machining is capable of improving surface integrity and with this, as practical implication, having high potential for improving the sliding conditions, fatigue life of the final product, corrosion resistance, etc. Originality/value: Originality of the paper is shown by novel solutions (patents) on cryogenic machining system (delivery) and in machined surface modification capabilities with alternative cooling/lubrication fluid.

7

Wpływ zużycia ostrzy na chropowatość powierzchni po frezowaniu stopu aluminium w obróbce kriogenicznej

Żurawski Ł., Storch B.

Mechanik

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2014

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R. 87, nr 8-9CD2

169—179

8

The influence of cooling techniques on surface roughness and tool wear during cryogenic machining

Wstawska I., Ślimak K.

Archives of Mechanical Technology and Automation

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2014

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Vol. 34, no. 2

51--59

EN

The main objective of this work is a comparision of different cooling techniques, namely cutting zone cooling, cutting tool cooling and workpiece cooling. The literature survey related to the analysis of surface texture (Ra) and tool wear (VBc) after applying different cooling techniques was also taken into account. The analysis revealed that the applied cooling technique has a significant influence on the values of parameters of surface’s roughness. Furthermore, in all cases observed, there was a positive influence of cryogenic machining on selected physical and technical aspects after turning and milling such materials as Inconel 718, titanium alloy Ti-6Al-4V, aluminium alloys and elastomers. This work can also be considered as a starting point for further research and the analysis of machinability during cryogenic machining.

PL

Celem niniejszego artykułu było porównanie metod obróbki kriogenicznej: chłodzenia strefy skrawania, chłodzenia przedmiotu obrabianego oraz chłodzenia narzędzia. Przedstawiono wpływ powyższych metod na chropowatość powierzchni obrobionej (Ra) oraz zużycie narzędzia (VBc). Porównanie wykazało istotny wpływ metody obróbki na chropowatość powierzchni obrobionej. Ponadto we wszystkich przypadkach zauważono pozytywny wpływ obróbki kriogenicznej na wybrane właściwości fizyczne po toczeniu i frezowaniu takich materiałów, jak: Inconel 718, stop tytanu Ti-6A1-4V, stopy aluminium, oraz materiały elastomerowe. Może to stanowić punkt wyjścia do dalszych badań skrawalności materiałów w niskiej temperaturze.

9

Cryogenic treatment and PVD coatings to augment wear resistance of tool steels

Peña-Parás L., Trejo Montemayor L. A., Ramírez Cantú S., Fernández Corona R. D., Reyna Reyes M.

Tribologia

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2013

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nr 3

109--117

EN

The influence of deep cryogenic treatment and PVD coatings on the wear resistance and toughness of D2, S7, H13 and M4 tool steels were studied. Three different PVD coatings were applied after heat treatment: AlCrN, TiAlN, TiCrN. In order to research the wear resistance, the ball-on-disk tribological test was used per ASTM G-99; material toughness was evaluated through the Charpy-V test. Wear scars were examined through optical microscopy to calculate the volume loss. It is found that cryogenic treatment improved wear resistance and toughness up to 63% and 12% respectively. The material with the best combination of wear resistance properties and toughness was S7 with cryogenic treatment and TiAlN coating.

PL

W pracy przedstawiono wyniki badań wpływu obróbki kriogenicznej i powłok PVD na odporność na ścieranie oraz udarność stali narzędziowych D2, S7, H13 i M4. Zastosowano trzy różne powłoki PVD: AlCrN, TiAlN, TiCrN, które wcześniej poddano obróbce cieplnej. W celu zbadania odporności na zużycie przeprowadzono badania z użyciem testera kula-tarcza zgodnie z wymogami normy ASTM G-99. Udarność została oceniona z wykorzystaniem młota Charpy’ego. Zużycie objętościowe zostało zmierzone za pomocą mikroskopu optycznego. Stwierdzono, że obróbka kriogeniczna polepszyła odporność na ścieranie o 63%, a udarność o 12%. W wyniku przeprowadzonych badań stwierdzono, że materiałem o najlepszych właściwościach na ścieranie i udarność jest stal narzędziowa S7 poddana obróbce kriogenicznej i pokryta powłoką TiAlN.

10

Effect of deep cryogenic treatment on substructure of HS6-5-2 high speed steel

Jeleńkowski J., Ciski A., Babul T.

Journal of Achievements in Materials and Manufacturing Engineering

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2010

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Vol. 43, nr 1

80-87

EN

Purpose: The purpose of this study was using of transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) in order to reveal the changes in substructure of speed steel made with deep cryogenic treatment (DCT), in comparison with substructure formed by conventional heat treatment for secondary hardness. Design/methodology/approach: The HS6-5-2 high speed steel was heat treated in a conventional mode for secondary hardness or was processed in a mode with use of DCT, with and without next tempering. Transmission electron microscopy and scanning electron microscopy observations were carried out. Studies of thermal stability in range of temperatures from -196 °C to 400 °C were performed using differential scanning calorimetry (DSC). Findings: Observations made with aid of SEM-TEM microscope revealed the presence of high density of globular clusters situated at dislocations, and precipitations of the fine carbide plates, located in twinned crystals of martensite. Thermal analysis (DSC) showed an occurrence of higher exothermic effects in specimens treated with use of DCT, than in specimens heat treated conventionally. In steel samples after quenching and DCT the additional exothermic effect was observed. Electron diffraction in TEM studies of these specimens allowed to observe reflections of which indexing exhibited that the precipitated carbide phase has crystallographic structure of B1 type. Research limitations/implications: Extremely high dispersion of carbide phases and a high state of stress that accompanies the stage of precipitation, make difficult the identification of the lattice structure of precipitations, its crystallographic relationships and the degree of coherence with the matrix. Identification of the type of carbides (ĺ, ç, B1, and others) and their coherence with matrix become time-consuming. This important issue requires detailed studies using high-resolution microscopes. Conditions of the early stage of the precipitation process affect the stability of induced strengthening and service-life of tools. Practical implications: Research of HS6-5-2 high speed steel allowed concluding that DCT, besides refinement of martensite grain size, causes an increase of quantity of sites for nucleation of clusters, in which during tempering the B1 carbides are formed. These fine, coherent with matrix and stable carbides are found to be responsible for enhancement of toughness and wear resistance of HSS tools. Originality/value: The issue of DCT is a niche topic in Poland, there are no detailed studies on the changes taking place during this process.

11

Achievements of sustainable manufacturing by machining

Kopac J.

Journal of Achievements in Materials and Manufacturing Engineering

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2009

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Vol. 34, nr 2

180-187

EN

Purpose: Manufacturing industry is under increasing pressure of global competition, stricter environmental legislation and supply-chain demand for improved sustainability performance. The latter can be achieved through changes in products, processes and systems which are related to the sustainability issues. Sustainability in manufacturing is an appropriate approach; however it is still unified to a higher production rate and benefit. To encounter this problem academic, scientific, cultural and human organizations have to find the way, on a highest level of decision; maybe to rise the sustainability over production growth. This paper also presents some results from modelling and optimization of sustainable machining of Inconel 718. High temperature alloys, such as Nickel and Titanium alloys, pose significant difficulty in machining, due to their unique thermo-mechanical properties. Design/methodology/approach: In the paper are presented and evaluated two sustainable machining alternatives: cryogenic machining and high pressure assisted machining in comparison to conventional machining. The sustainability performance measures refer to environmental impact, energy consumption, safety, personal health, waste management and costs. The sustainability evaluation is supported with machining experiments on high-temperature Ni-alloy (Inconel 718). It is shown that tooling costs are presenting the major contribution to the overall production costs, when hard-to-machine materials are machined, what is contradictory with previous analysis. Findings: As a result, it is shown that sustainable machining alternatives offer economic, environmental and social performance improvement in comparison to conventional machining. The results of the experimental part show that appropriate cooling/lubrication application can provide improved overall machining performance while satisfying sustainable issues in terms of enhanced machined surface quality, tool-life, chip breakability, power consumption and increasing productivity. Research limitations/implications: The Faculty of Mechanical Engineering in Ljubljana, Slovenia is implementing two new cutting strategies for the machining of a special material – Inconel. The first one is cryogenic machining and the second is material cutting by assistance of high pressure jet cooling lubrication. Both machining strategy are in rang of sustainable manufacturing. The implications of processes like those are not only nature friendly, but also modern spirit for producers and users of products. Originality/value: Paper present the technical description of two modern machining processes, the comparison of them and benefit, advantages and disantvantages. Really new is the strategy and opinion of spirit, which can be included in product over sustainable manufacturing processes.

12

The influence of deep cryogenic treatment on transformations during tempering of quenched D2 steel studies of XRD, structures, DSC, dilatometry, hardness and impact energy

Wierszyłłowski I., Samolczyk J., Wieczorek S., Andrzejewska E., Niemczyk W.

Obróbka Plastyczna Metali

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2008

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T. 19, nr 2

53-59

EN

The study analyses the influence of cryogenic treatment on the resultant structures, the development of changes during tempering and the properties obtained. It was observed that cryo treatment affects the properties through: a significant reduction in retained austenite content, gradual reduction in value of martensite tetragonality and an increase in the number of carbon atoms participating in transformations during tempering. The consequence of the transformations taking place during cryogenic treatment is precipitation of ?-carbide instead of ?-carbide during low tempering. The number of ?-carbides precipitated is higher than that of ?-carbide. This affects the functional characteristics of steel.

PL

Podczas badań analizowano wpływ obróbki kriogenicznej na uzyskane struktury, przemiany podczas odpuszczania i uzyskiwane właściwości. Stwierdzono, że obróbka kriogeniczna wpływa na właściwości wskutek znacznego zmniejszenia zawartości austenitu szczątkowego, stopniowego obniżenia tetragonalności martenzytu i zwiększenia liczby atomów węgla biorących udział w przemianach podczas odpuszczania. W wyniku przemian zachodzących podczas obróbki kriogenicznej podczas odpuszczania wydziela się węglik ? zamiast węglika ?. Liczba węglików ? wydzielających się podczas odpuszczania jest większa niż liczba wydzielających się podczas obróbki konwencjonalnej węglików ? . Zmiany te mają wpływ na właściwości użytkowe stali.

13

The optimization of the cryogenic processing Al-Cu alloys

Stankowiak A., Bydałek A. W.

Archives of Foundry Engineering

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2007

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Vol. 7, iss. 3

141-146

EN

In the article was introduced the investigations defining optimization of the cryogenic processing after saturating the alloy AlCu4, 7. The qualification of the influence this processes was planned (in the function of temperature and time) on microstructure and the mechanical proprieties of this alloy. There are accept the wide range of the temperature 175oC - 350oC there made possible the settlement of the influence of the temperature of aging on the kinetics of the break-up of the permeated with solution [alpha] and then on the change of microstructure and mechanical proprieties. There were applied the times of aging from 30 to 240 min. Results of investigations were compared with results after such thermal processing itself without the cryogenic processing after saturating.

14

The influence of the cryogenic processing after saturating on propriety AlCu4,7 cast alloy

Stankowiak A., Bydałek A. W.

Archives of Foundry Engineering

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2007

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Vol. 7, iss. 2

147-152

EN

In the article was introduced the investigations defining influence of the cryogenic processing after saturating on the processes of the effusion consolidation of the alloy AlCu4,7. The qualification of the influence this processes was planned (in the function of temperature and time) on microstructure and the mechanical proprieties of this alloy. There are accept the wide range of the temperature 175 ÷ 350[degrees]C there made possible the settlement of the influence of the temperature of aging on the kinetics of the break-up of the permeated with solution . and then on the change of microstructure and mechanical proprieties. There were applied the times of aging from 30 to 240 min. Results of investigations were compared with results after such thermal processing itself without the cryogenic processing after saturating.

15

Wpływ temperatury hartowania i obróbki kriogenicznej na właściwości stali NC11LV

Niemczyk W., Wierszyłłowski I.

Inżynieria Materiałowa

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2006

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Vol. 27, nr 3

225-228

PL

W pracy badano wpływ temperatury hartowania i niskotemperaturowej obróbki kriogenicznej na twardość i udarność stali NC11LV po hartowaniu i odpuszczaniu. Wzrost temperatury hartowania powoduje wyraźny wzrost twardości i obniżenie udarności. Twardość jest większa i wzrasta szybciej w próbkach obrabianych kriogenicznie po hartowaniu, udarność tych próbek jest natomiast mniejsza. Obróbka kriogeniczna powoduje znacznie mniejsze obniżenie twardości po godzinnym odpuszczaniu w 170°C, udarności próbek po obróbce kriogenicznej są prawie identyczne z nie poddanym tej obróbce. Dodatkowe dwugodzinne odpuszczanie w 450°C po hartowaniu i odpuszczaniu w 170°C spowodowało mniejsze obniżenie twardości próbek po obróbce kriogenicznej niż próbek nie poddanych tej obróbce. Udarność próbek nie poddanych obróbce kriogenicznej była nieco wyższa niż próbek po tej obróbce. Udarność określano na próbkach bez karbu, twardość badano metodą HRC. Przeprowadzono analizę uzyskanych wyników wykorzystując opublikowane wcześniej badania własne i literaturę.

EN

The influence of hardening temperature and deep cryogenic treatment on hardness and impact toughness after quenching and tempering was analyzed. The increase of quenching temperature caused increase of hardness , change of impact toughness is not significant .Due to cryogenic treatment after quenching hardness of this samples is higher then not cryogenic treated. Due to tempering by one hour at 170°C hardness decreases. The decrease for cryogenic treated samples after quenching is smaller than samples quenched only. The impact toughness decrease is similar for cryogenic treated and not cryogenic treated samples. Hardness of samples tempered at 170°C decreases due to additional tempering by two hours at 450°C . The decrease was less for cryogenic treated samples. The impact toughness was higher for not cryogenic treated samples, but difference was not significant. The impact toughness was determined on samples without notch, the hardness was determined according to HRC method.

16

Wpływ obróbki kriogenicznej po przesycaniu na odporność na ścieranie starzonego stopu Al-4,7%Cu

Stankowiak A., Wierszyłłowski I.

Inżynieria Materiałowa

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2006

|

Vol. 27, nr 3

276-279

PL

Przedstawiono wpływ obróbki kriogenicznej po przesycaniu na odporność na ścieranie i twardość starzonego w temperaturach od 175 do 220 0C stopu Al.-4,7%Cu. Zastosowano czasy starzenia od 30 do 240 min. Wyniki porównano z wynikami uzyskanymi po takiej samej obróbce cieplnej bez obróbki kriogenicznej po przesycaniu. Badania odporności na ścieranie przeprowadzono stosując papiery ścierne o wielkości ziarna od 400 do 1000 , stałym docisku próbki siłą 5,4N i stałej prędkości 83 obr./min . Większą odporność na ścieranie uzyskano dla tych próbek, których twardość była większa.

EN

The influence of deep cryogenic treatment (DCT) on fiction resistance and hardness of supersaturated and aged Al.- 4.5 Cu Mass % alloy was studied. DCT was performed immediately after supersaturation from 520 oC, after that, ageing at temperatures region of 175 -220 oC by times of 30, 120 and 240 min. was executed. The results were compared with that obtained from the similar experiments without DCT. Friction resistance studies were performed with use of abrasive paper of 400 to 1000 grains grade, constant load of sample 5.4 N and 83 r.p.m. Friction resistance was higher for harder specimens obtained with application of DCT. Obtained results were analyzed and discussed on the basis of the possible influence of DCT on process of ageing.

17

Wpływ obróbki kriogenicznej po hartowaniu na przemiany zachodzące podczas odpuszczania wybranych stali narzędziowych. Badania dylatometryczne i DTA

Wierszyłłowski I., Szcześniak L.

Obróbka Plastyczna Metali

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2005

|

T. 16, nr 1

31-36

PL

W pracy porównano zmiany zachodzące podczas izochronicznego odpuszczania stali NC10, NC11LV i SW7M zaraz po hartowaniu oraz po hartowaniu i obróbce kriogenicznej. Zmiany badano metodą dylatometryczną i DTA. Stwierdzono, że obróbka kriogeniczna powoduje wyraźne obniżenie temperatury początku wydzielania węglików a ilość wydzielonych węglików jest większa. Wzrost zawartości węglików jest większy niż to wynika z podwyższonej wskutek obróbki kriogenicznej zawartości martenzytu .

EN

On the basis of results of dilatometric and DTA studies of isochronal tempering of quenched and quenched and cryogenic treated tool steels (NC10, NC11LV, SW7M) it was found that cryogenic treatment accelerate the tempering processes and increases accompanying them contraction. The contraction is much bigger then that resulting from the amount of martensite increase because of residual austenite transformation during cryogenic treatment. The DTA analysis supports obtained results.