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EN
This study concerns the wear behaviour of metal couples used in industry, particularly in mechanical sliding systems (numerically controlled machine tools). In general, the nature of the materials of the parts of these systems which are in contact and move relatively, are medium carbon steels, thanks to their good mechanical and tribological properties. The present work aims to study, the dry sliding wear of the contact surface of the pin (machine slide) against the contact surface of a disc (machine groove) and the damage induced on the worn track. The pin is AISI 1038 and AISI 1045 steel, the disc is AISI 1055 steel. The tribological tests were carried out on a pin-disc tribometer, in an atmospheric environment. The wear of the pins being evaluated by weighing and studied according to the hardness of the pin with the variation of the normal load applied. The discussion of the results is based on SEM observations and EDS analyzes of worn surfaces and interfacial phenomena produced by dynamic contact. The results obtained indicated the influence of the applied load and the hardness on the wear of the pin and therefore on the tribological behaviour of the worn surfaces.3--10
EN
The presented work was mainly aimed at assessing the tribological properties of gas nitrided samples subsequently subjected to shot peening. This assessment was carried out using the standard “three rollers – cone” method. In these tests, different materials of roller samples were used, i.e. both structural and tool steels. In addition, the selected material of conical counter-samples, i.e. heat-treated medium carbon steel, was used. The obtained test results allowed us to assess the influence of the use of dissimilar material of nitrided (under different conditions) roller samples, as well as their surface plastic processing, i.e. shot peening.
PL
Prezentowana praca miała głównie na celu ocenę właściwości tribologicznych próbek azotowanych gazowo i następnie kulowanych. Ocenę tę przeprowadzono znormalizowaną metodą „trzy wałeczki – stożek”. W próbach tych użyto zróżnicowane materiały próbek wałeczkowych, tzn. zarówno stale konstrukcyjne, jak i narzędziowe. Ponadto zastosowano wybrany materiał przeciwpróbek stożkowych, tj. ulepszaną cieplnie stal średniowęglową. Uzyskane wyniki badań pozwoliły ocenić wpływ stosowania zróżnicowanego materiału azotowanych (w różnych warunkach) próbek wałeczkowych, a także ich powierzchniowej obróbki plastycznej, tzn. kulowania.
3
Content available remote Poprawa własności stali typu maraging w postaci kęsów kutych
PL
W pracy opisano badania prowadzące do poprawy własności mechanicznych (ciągliwości) stali typu maraging X2NiCoMo18-9-5 w postaci kęsów kutych o dużym przekroju. Zmodyfikowano proces kucia poprzez zastosowanie większych odkształceń plastycznych w niższych wartościach temperatury w stosunku do tradycyjnej technologii. Opracowano też nową trój-etapową obróbkę cieplną odkuwek. Korzystne zmiany własności przypisano zmniejszonej wielkości ziarna austenitu oraz rozdrobnieniu wtrąceń niemetalicznych.
EN
The paper describes experiments leading to the improvement in the mechanical properties (ductility) of the X2NiCoMo18-9-5 maraging steel in the form of forged billets of a large cross-section. The forging process was modified in relation to the traditional technology by applying higher deformations at lower temperatures. A novel three-stage heat treatment was also developed. The improvement of the properties was attributed to the austenite grain refinements and finer size of non-metallic inclusions.
EN
The problem of heat treatment of wet materials contains the question of the heat and mass inside the body transfer (an internal problem) and in the boundary layer at the interface between phases (an external problem). The amount of removable moisture depends on the degree of each of these processes development. When heated, the moisture content on the surface decreases, creating a concentration difference across the body. Therefore, a flow of moisture occurs in the body from deep layers to the surface, towards which the flow of heat is directed. Thus, when wet materials are heated, complex processes of moisture and heat exchange occur, mutually affecting the enthalpy and moisture content of both the heated material and the environment. The features of mathematical model construction of heating and drying of wet materials process are considered in the article. The drying process is defined as a thermal process with effective heat transfer coefficients with consideration of mass transfer. It makes it possible to obtain analytical dependencies that are convenient for engineering calculations, with which you can determine the temperature field and evaluate the kinetics of wet materials drying.
PL
Problem obróbki cieplnej wilgotnych materiałów obejmuje zagadnienia transferu ciepła i masy wewnątrz komponentu (problem wewnętrzny) i w warstwie granicznej z przemianą fazową (problem zewnętrzny). Ilość usuwanej wilgoci zależy od stopnia rozwoju każdego z tych procesów. Po podgrzaniu zawartość wilgoci na powierzchni zmniejsza się, tworząc różnicę koncentracji w całym materiale. Dlatego w materiale występuje przepływ wilgoci z głębokich warstw na powierzchnię, na którą skierowany jest przepływ ciepła. Oznacza to, że gdy ogrzewane są wilgotne materiały, zachodzą złożone procesy wymiany wilgoci i ciepła, wpływając wzajemnie na entalpię i zawartość wilgoci zarówno ogrzewanego materiału, jak i środowiska.W artykule omówiono cechy budowy modelu matematycznego procesu ogrzewania i suszenia materiałów zawilgoconych. Proces suszenia definiuje się jako proces termiczny o efektywnych współczynnikach przenikania ciepła z uwzględnieniem transferu masy. Umożliwia uzyskanie zależności analitycznych dogodnych do obliczeń inżynierskich, za pomocą których można określić pole temperatury i ocenić kinetykę suszenia wilgotnych materiałów.
PL
Niniejszy artykuł stanowi kontynuację badań nad obróbką cieplną (OC) cynkowej powłoki zanurzeniowej, naniesionej na stal i żeliwo szare. Obróbka ta powoduje zmiany w strukturze powłoki, co bezposrednio przekłada się na jej właściwości mechaniczne i użytkowe. W poprzednich publikacjach analizowano wpływ OC w zakresie temperatur: 390 ÷ 530ºC. Obróbka ta spowodowała istotne zwiększenie twardości powłoki cynkowej, jednak wiązało się to także z niekorzystnym efektem - znacznym zmniejszeniem odporności korozyjnej w stosunku do próbek bazowych, których nie poddano OC [9]. Zmiana odporności korozyjnej była skutkiem nieciągłości – pękniec, które pojawiły sie w powłoce w następstwie zbyt wysokiej temperatury OC. Obróbka w zakresie niższych temperatur, tj. 270 ÷ 350ºC nie powoduje tak istotnego obniżenia odporności korozyjnej, weryfikowanej za pomocą przyspieszonych badań w komorze solnej wg ISO 9227 (solanka obojętna). Oprócz odporności na korozję mierzono także wpływ OC na inne właściwości powłoki cynkowej, tj.: odporność na ścieranie – przy zastosowaniu testera T-11 oraz zmianę twardosci, mierzoną metodą Vickersa -HV 0,02, dedykowaną do cienkich powłok. Przeprowadzone badania dowiodły korzystnego wpływu przeprowadzonej niskotemperaturowej obróbki cieplnej w odniesieniu do otrzymanych wartości badanych właściwosci mechanicznych powłoki cynkowej.
EN
This paper contains a continuation of research on the heat treatment (OC) of a hot-dip zinc coating applied to steel and cast iron. This treatment causes changes in the structure of the coating, which directly influences its mechanical and functional properties. In previous publications, the influence of OC in the range of 390 ÷ 530ºC was analyzed. The above-mentioned treatment resulted in a significant increase in the hardness of the zinc coating, but it was also associated with an adverse effect – a significant reduction in corrosion resistance compared to the base samples [9]. The decrease in corrosion resistance is the result of discontinuities in the coating resulting from treatment at too high temperature. Machining at lower temperatures, i.e. 270-350ºC, does not cause such a significant reduction in corrosion resistance, verified by accelerated corrosion tests in a salt chamber according to ISO 9227 (NSS Test). In addition to corrosion resistance, the impact of OC on other properties of the zinc coating, i.e. abrasion resistance using the T-11 tester and analysis of hardness changes, carried out using the Vickers -HV 0.02 method, dedicated to thin coatings. The tests proved the beneficial effect of the low-temperature heat treatment carried out in relation to the obtained values of the tested mechanical properties of the zinc coating.
6
EN
A recent development in the material studies provides beneficial application of lightweight alloys such as aluminium, magnesium as well as composites and metal matrices. The alloys are experimentally improved by increasing hardness in the ballistics testing using projectiles,makes them viable for the areas such as aerospace, military, defence, automobiles and so on. So the study is made on different approaches. First, by comparing different types of non-ferrous alloys and projectiles regarding sizes, structures. Second, the materials with heat treatment are also studied for investigating the hardness property by overcoming successful penetration on non-ferrous alloys. Third, material to be improvised by use of numerical studies such as 3D models, empirical models and software such as ANSYS, ABAQUS and AUTODYN, etc. Finally, the aim of this paper is to review the recent progress ballistic studies of lightweight materials and to provide a best choice of material for further on-going research.
EN
Purpose: The paper presents the results of microstructure, surface development and thickness of the oxide layer on the pure titanium Grade 2 after mechanical activation and heat treatment (550°C/5h). Design/methodology/approach: Studies show that it is possible to control the thickness of the oxide layer by using different materials to change the roughness of surface - mechanical activation before heat treatment. After mechanical activation and heat treatment, the results of the thickness of the oxide layer as well as a level of surface development were obtained, presented and discussed. Findings: The conducted research have proved that mechanical activation of the surface which cause increase of surface development results in greater thickness of oxide layer which is formed during heat treatment. Nevertheless mechanical activation that results in decrease of surface development, such as polishing, results in decrease of oxide layer thickness. Research limitations/implications: The conducted research have showed up that mechanical activation of the surface which cause increase of surface development results in greater thickness of oxide layer which is formed during heat treatment. Nevertheless, mechanical activation that results in decrease of surface development, such as polishing, results in decrease of oxide layer thickness. Practical implications: are possible using similar method for passivation titanium alloys for medical application. Originality/value: The paper presents the possibility of using mechanical preactivation of surface before heat treatment passivation.
EN
Purpose: To present a technology for hardfacing of metal-cutting tools by arc welding in vacuum. Design/methodology/approach: The experiments were carried out using an installation for arc welding in vacuum. Objects of research were metal cutting tools (lathe knives), made of high-speed steel HS6-5-2 on a base metal of structural steel C45. The structure, hardness and wear resistance after hardfacing and after a triple tempering at 560°C have been determined. The heat resistance of the obtained instruments has been examined. Findings: The microstructural analysis showed that the structure of the built-up layer consisted of martensite, retained austenite and carbides. This was confirmed by the values of measured hardness after welding which were about 63-64 HRC. The triple tempering led to an increase in hardness by 3-4 HRC. It was found that the built-up layers (cutting edges of tools) retain their hardness (HRC=63-65) up to a temperature of 615-620°C, which shows that the heat resistance of the build-up layers was similar to that of the hardened and tempered tools of the same steel. The built-up work-pieces (excluding heat treated) and the reference knife showed the same cutting qualities at cutting speeds in the range of 55 to 120 m/min. It has been found that triple tempering after hardfacing led to increased wear resistance and consequently the durability of the tool also increased due to the higher hardness. Practical implications: The practical application is related to the production of metalcutting tools. Originality/value: The proposed technological method allows to produce defects free built-up layers. The cutting properties of the built-up in vacuum layers are comparable to or better than those of new tools made of steel HS 6-5-2.
EN
The aim of the research was to analyse the influence of the initial heat treatment of polyacrylonitrile fibres on their sorption properties in relation to selected basic and disperse dyes, in order to select the dyeing variants most beneficial from the point of view of increasing the sorption capacity of commonly used dyes and improving the dyeing process. Research was carried out on a fibre produced on an industrial scale, using dyes of basic application importance, which differ in the diffusion properties of the molecules and the mechanism of binding with the fibre material. Thermal treatment of the fibre was carried out in various media (air, water, steam), with various variants of the temperature and its duration, i.e. under the conditions commonly used in fibre preprocessing processes and their "improvement". During the research, several different measurement methods were used to assess changes in the molecular and supramolecular structure of the fibre material: the infrared absorption spectroscopy method, the critical fibre dissolution measurement method, the densitometric method, and the interferential polarisation microscopy method. Fibre sorption changes resulting from the modification of the structure of the fibre under the influence of thermal treatment were analysed from the point of view of improving the efficiency of dye use and shortening the dyeing time based on commonly accepted values of the sorption index Cb and kinetic sorption index: t0.5 for basic dyes and t0.7 for disperse dyes.
PL
Celem badań było określenie wpływu wstępnej obróbki cieplnej badanych włókien poliakrylonitrylowych na ich właściwości sorpcyjne w stosunku do wybranych barwników zasadowych i zawiesinowych. Badania prowadzono na włóknach produkowanych w skali przemysłowej, używając barwników o dużym znaczeniu aplikacyjnych, różniących się właściwościami dyfuzyjnymi cząsteczek oraz mechanizmem wiązania z tworzywem włókna. Obróbkę termiczną prowadzono w różnych mediach (powietrze, woda, para wodna), w różnych wariantach temperatury i czasu jej trwania. W badaniach zastosowano metody pomiarowe, pozwalające oceniać zmiany parametrów budowy cząsteczkowej i nadcząsteczkowej tworzywa włókien: metodę spektroskopii absorpcyjnej w podczerwieni, metodę pomiaru krytycznego czasu rozpuszczania włókien, metodę densytometryczną oraz metodę mikroskopii interferencyjno-polaryzacyjnej. Zmiany zdolności sorpcyjnej włókien analizowano z punktu widzenia poprawy efektywności wykorzystania barwników i skrócenia czasu barwienia w oparciu o wartości wskaźnika sorpcji Cb oraz kinetycznych wskaźników sorpcji: t0,5 dla barwnika zasadowego i t0,7 dla barwników zawiesinowych.
EN
The article discusses the effect of annealing temperature applied during heat treatment as well as the suitability of preheating before the welding of butt joints in pipes (having a diameter of 33.7 mm and a wall thickness of 4.5 mm) made of steel X10CrMoVNb9-1 (P91). In the article, the structure and properties of a joint subjected to heat treatment performed in accordance with manufacturing standards concerning power unit elements are compared with those of a joint not subjected to heat treatment. The welding process discussed in the paper was based on the TIG method and involved the use of filler metal Thermanit MTS 3 (W Cr Mo 91). The material of steel X10CrMoVNb9-1 after welding and not subjected to heat treatment is both very hard and brittle. Because of the fact that the power engineering steel of the above-presented characteristics cannot be exposed to the effect of a high-pressure and high-temperature medium (due to possible crack formation), the welding of such steel should be followed by appropriate post-weld heat treatment.
PL
Poddano ocenie wpływ temperatury wyżarzania podczas obróbki cieplnej oraz zasadności zastosowania podgrzewania wstępnego przed spawaniem złączy doczołowych rur ze stali X10CrMoVNb9-1 (P91) o średnicy 33,7 mm i grubości ścianki 4,5 mm. Porównano struktury i własności złącza po obróbce cieplnej wykonanej zgodnie z normami wykonawczymi dla elementów bloków energetycznych ze strukturą i własnościami złącza niepoddanego obróbce cieplnej. Proces spawania przeprowadzono metodą TIG przy użyciu materiału dodatkowego Thermanit MTS 3 (W Cr Mo 91). Materiał stali X10CrMoVNb9-1 po spawaniu i bez obróbki cieplnej jest bardzo twardy i kruchy. Stal energetyczna w takim stanie nie sprawdzi się w warunkach oddziaływania dużego ciśnienia medium o wysokiej temperaturze i może to być przyczyną powstania pęknięć, dlatego też odpowiednia obróbka cieplna po spawaniu jest konieczna.
EN
The article presents results of tests concerning the effect of heat treatment on the structure and hardness of submerged arc welded joints made in steel 7CrMoVTiB10-10 (T24). The tests revealed that the welds made of steel 7CrMoVTiB10-10 required post-weld heat treatment at a temperature 750°C. The heat treatment was performed in order to protect welded structures from cracking during transport and operation as well as to prevent the development of secondary hardness.
PL
Przedstawiono wyniki badań wpływu obróbki cieplnej na strukturę i twardość spoin złączy spawanych łukiem krytym stali 7CrMoVTiB10-10 (T24). Wykazano, że spoiny złączy spawanych stali 7CrMoVTiB10-10 po procesie spawania wymagają obróbki cieplnej w temperaturze 750°C, w celu zabezpieczenia konstrukcji przed pękaniem podczas ich transportu i eksploatacji oraz w celu uniknięcia zjawiska twardości wtórnej.
12
Content available remote Problems accompanying repairs of chemical equipment
EN
The paper presents problems experienced during repairs of structures operated at high temperature for a long time. Research-related TOFD method-based ultrasonic tests revealed indications implying the presence of unacceptable imperfections in welded joints. Attempted repairs involving the use of welding methods proved ineffective as the welding and heat treatment processes resulted in the formation of cracks. The tests and analysis of the above-named issue revealed that the reason for repair-related problems lay in relaxation cracks triggered by excessively high stresses in the joints and improper parameters of heat treatment to which the steel of the boiler was subjected. The welding technology developed as a result of the study enabled the performance of the proper repair of related equipment and made it possible to re-start the production.
PL
W pracy przedstawiono problemy występujące przy remontach konstrukcji długo eksploatowanych w podwyższonej temperaturze. Podczas kontrolnych badań ultradźwiękowych metodą TOFD w złączach spawanych stwierdzono niedopuszczalne wskazania niezgodności. Próby naprawy metodami spawalniczymi okazały się nieskuteczne, bowiem po spawaniu i obróbce cieplnej stwierdzano nowe pęknięcia. Wykonane badania i analiza problemu wykazała, że przyczyną trudności przy naprawie spoin są pęknięcia relaksacyjne wywołane wysokimi naprężeniami w złączach i nieodpowiednimi parametrami obróbki cieplnej stali, z której był wykonany kocioł. Opracowana technologia spawania pozwoliła prawidłowo wykonać remont o uruchomić produkcję.
EN
The paper presents the results from a study on the impact of the cooling rate in the eutectoid transition on the abrasive wear of the as cast Zn-4Al alloy. The microstructure of the researched material consists of dendrites of the η solid solution and an (α+η) eutectic structure. During the eutectoid transformation at 275oC the distribution in the eutectic structure was transformed and fined. Heat treatment was carried out for this alloy, during which three cooling mediums were used, i.e. water, air and an furnace. For the research material obtained in this way, metallographic examinations were performed using the methods of light and scanning electron microscopy, as well as hardness measurements. It was found that faster cooling rate promoted the fragmentation of structural components, which translates into higher hardness of the material. This also had effects in the tribological wear of the tested alloy. As part of the tests, an abrasive wear test was carried out on a standard T-07 tester.
14
Content available Influence of Zr on AlSi9Cu1Mg Alloy Cast in Ceramic
EN
The article focuses on the analysis of the effect of Zr on the properties of the aluminium alloy AlSi9Cu1Mg. The effect of Zr was evaluated depending on the change in mechanical properties and heat resistance during a gradual addition of Zr with an increase of 0.05 wt. % Zr. Half of the cast experimental samples from each variant were heat treated by precipitation hardening T6 (hereinafter HT). The measured values in both states indicate an improvement of the mechanical properties, especially in the experimental variants with a content of Zr ≥ 0.20 wt. %. In the evaluation of Rm, the most significant improvement occurred in the experimental variant with an addition of Zr 0.25 wt. % after HT and E in the experimental variant with addition of Zr 0.20 wt. % after HT. Thus, a difference was found from the results of the authors defining the positive effect of Zr, in particular at 0.15 wt. %. When evaluating the microstructure of the AlSi9Cu1Mg alloy after Zr alloying, Zr phases are already eliminated with the addition of Zr 0.10 wt. %. Especially at higher levels of Zr ≥ 0.20 wt. %, long needle phases with slightly cleaved morphology are visible in the metal matrix. It can be stated that a negative manifestation of Zr alloying is expressed by an increase in gassing of experimental alloys, especially in variants with a content of Zr ≥ 0.15 wt. %. Experimental samples were cast into ceramic moulds. The development of an experimental alloy AlSi9Cu1Mg alloyed with Zr would allow the production of a more sophisticated material applicable to thin-walled Al castings capable of operating at higher temperature loads.
EN
The study presented in this paper concerned the possibility to apply a heat treatment process to ductile cast-iron thin-walled castings in order to remove excessive quantities of pearlite and eutectic cementite precipitates and thus meet the customer’s requirements. After determining the rates of heating a casting up to and cooling down from 900°C feasible in the used production heat treatment furnace (vh = 300°C/h and vc = 200°C/h, respectively), dilatometric tests were carried out to evaluate temperatures Tgr, TAc1 start, TAc1 , TAr1 start, and TAr1 end. The newly acquired knowledge was the base on which conditions for a single-step ferritizing heat treatment securing disintegration of pearlite were developed as well as those of a two-step ferritization process guaranteeing complete disintegration of cementite and arriving at the required ferrite and pearlite content. A purely ferritic matrix and hardness of 119 HB was secured by the treatment scheme: 920°C for 2 hours / vc = 60°C/h / 720°C for 4 hours. A matrix containing 20–45% of pearlite and hardness of 180–182 HB was obtained by applying: 920°C for 2 hours or 4 hours / vc = 200°C/h to 650°C / ambient air.
EN
Heat treatment processes, due to qualitative requirements for the cast machinery components and restrictions on energy consumption resulting on the one hand from environmental concerns, and on the other hand from a requirements coming from minimization of manufacturing costs, are resulting in searching after a technologies enabling obtainment of satisfactory results, in form of improved mechanical properties mainly, while minimizing (limiting) parameters of successive operations of the heat treatment. Heat treatment of the T6 type presented in this paper consists in operations of heating of investigated alloys to suitably selected temperature (range of this temperature was evaluated on the base of the ATD method), holding at such temperature for a short time, and next rapid cooling in water (20ooC) followed by artificial ageing, could be such technology in term s of above mentioned understanding of this issue. Performed T6 heat treatment with limited parameters of solutioning operation resulted in visible increase in tensile strength Rm of AlSi7Mg, AlSi7Cu3Mg and AlSi9Cu3(Fe) alloys.
EN
This paper investigates the metallurgical behavior and mechanical properties of the P91 steel welds joint. The joint of heat-resistant P91 steel has been welded by the gas tungsten arc welding (GTAW) process using the dissimilar Inconel grade 617 filler. The P91 welds joints have been subjected to varying heat treatment regimes in the temperature range of 650–810 °C for 2 h. The normalizing-based tempering was also performed for the welded joint. The weld fusion zone (WFZ) with austenitic structure and heat-affected zones (HAZs) with martensitic structure was characterized using the optical microscope and scanning electron microscope (SEM). The detailed characterization of the weld metal and HAZ interface has also been performed for as-welded and post-weld heat treatment (PWHT) conditions. For mechanical properties of the welds joint, tensile testing and hardness testing were performed. The relationship between mechanical behavior and microstructure of the welded joint has been evaluated for as-welded and heat treatment conditions. The microstructure studies revealed the formation of an unmixed zone (UZ) close to the fusion line, and it was characterized as peninsula and island. The WFZ showed the complete austenitic mode of the solidification and revealed the austenitic structure with cellular and equiaxed grains in the center of the weld metal. The columnar and cellular dendrites were seen near the boat fusion line, i.e., interface of the weld metal and HAZ. The soft δ ferrite patches were observed near the fusion line in the area of HAZ and remain undissolved up to tempering temperature of 810 °C (PW 3). The dissolution of the ferrite patches was noticed for PW 4. The maximum and minimum tensile strength of the welds joint was measured 731 MPa and 502 MPa for PW 3 and PW 2, respectively. A uniform hardness variation in the transverse direction of the welded joint was observed for PW 3 and PW 4 conditions. The optimum combination of strength and ductility was obtained for the PW 3 condition.
18
Content available remote Research of mechanical and electrical properties of Cu–Sc and Cu–Zr alloys
EN
The research paper presents the impact of the scandium additive and various conditions of the heat treatment on copper mechanical, electrical and heat resistance properties. The performed research works included manufacturing of CuSc0.15 and CuSc0.3 alloys through metallurgical synthesis with the use of induction furnace and following crystallization in graphite crucibles at ambient temperature. Additionally, a CuZr0.15 alloy was produced as a reference material for previously syn-thesized Cu–Sc alloys. During research, the selection of heat treatment for the produced materials was conducted in order to obtain the highest mechanical–electrical properties ratio. Materials obtained in such a way were next subjected to thermal resistance tests. Parameters of thermal resistance test included temperatures from the range of 200–700 °C and 1 h of anneal-ing time. The research has shown that CuSc0.15 and CuSc0.3 alloys have higher heat resistance after their precipitation hardening compared to the Cu–Zr alloy. The paper also presents microstructural research of the produced materials, which showed that alloying elements precipitates are mainly localized at the grain boundaries of the material structure.
EN
This paper deals with different types of artificial ageing and its effect upon the mechanical properties of an aluminium alloy. For the purposes of this research, the EN AW 2017 alloy was subjected to different types of heat treatment. These samples were subjected to different analyses. The results of hardness measurements (HB and HV) revealed the highest values of the non‑heat treated sample. The static tensile stress test proved the highest ductility of the heat treated samples. Overall, the best were revealed for the sample artificially aged at 160°C.
EN
Support of planning heat treatment processes in small batch production is very complex. In the analysed case, the bottlenecks of the processes were located on heat treatment. The difficulty in planning is due to necessity of adapting available resources to changing demand requirements. In the conditions of unit production crucial role plays changeovers time, availability of resources and cost of processing. Due to NP- difficult nature of optimization a simplified method was used. It was a complex of theory of constraints and dynamic task grouping. This is one of the attempts to solve the supporting process production problem with a method enabling its practical use.
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