Wyniki wyszukiwania - BazTech

1

Refractory metals as alloying additives for metallic materials formed via powder metallurgy techniques

Duda Alicja, Kopyciński Bartosz, Matula Grzegorz, Wrona Adriana

Ochrona przed Korozją

|

2024

|

nr 3

68--76

EN

Methods for the fabrication of metallic sinters via powder metallurgy techniques have been widely discussed in materials engineering for many years. Depending on the final purpose of the finished products, it is primarily important to ensure their appropriate mechanical properties. Numerous works on this topic are devoted mainly to the modification of conventional metallic materials, and one of the promising research directions is the addition of refractory metals to metal alloys. Thanks to the advantageous impact on thermal stability, mechanical properties, and corrosion resistance, the proposed solutions fit perfectly into the trends of searching for new, functional engineering materials. This work presents a review of scientific reports on the modification of metal alloys with the addition of refractory metals published over the last 15 years. First, a brief characterization of refractory metals along with a description of the basics of processing metallic materials using powder metallurgy are presented. In the following part of the article, the research results on the influence of the addition of high-melting metals on the mechanical properties and corrosion resistance of heavy and light metal alloys are discussed. The conclusion consists of data on the global metal alloys market, taking into account its current state and forecasted changes for the next few years.

PL

Metody spieków metalicznych technikami metalurgii proszków są szeroko omawiane w inżynierii materiałowej od wielu lat. Niezależnie od przewidywanego przeznaczenia gotowych wyrobów istotne jest przede wszystkim zapewnienie produktom odpowiednich własności mechanicznych. Liczne prace poświęcone tej tematyce skupiają się głównie na modyfikacji konwencjonalnych materiałów metalicznych, a jednym z obiecujących kierunków badań jest wzbogacanie stopów metali dodatkiem metali wysokotopliwych. Dzięki korzystnemu wpływowi na stabilność termiczną, własności mechaniczne i odporność na korozję proponowane rozwiązania doskonale wpisują się w poszukiwania nowych, funkcjonalnych materiałów inżynierskich. Praca stanowi przegląd doniesień naukowych opublikowanych w ciągu ostatnich 15 lat, traktujących o modyfikacji stopów metali dodatkiem metali wysokotopliwych. W pierwszej kolejności przedstawiono krótką charakterystykę metali wysokotopliwych wraz z omówieniem podstaw przetwarzania materiałów metalicznych z wykorzystaniem metalurgii proszków. W dalszej części artykułu przeprowadzono analizę wyników badań nad wpływem dodatku metali wysokotopliwych na własności mechaniczne oraz odporność korozyjną stopów metali ciężkich i lekkich. W podsumowaniu przybliżono dane dotyczące stanu globalnego rynku stopów metali wraz z uwzględnieniem zmian prognozowanych na najbliższe lata.

2

Badania skrawalności stopu o wysokiej entropii FeCrCoMnNi przy toczeniu narzędziem diamentowym wspomaganym drganiami ultradźwiękowymi

Jemielniak Krzysztof

Mechanik

|

2022

|

R. 95, nr 1

10

PL

Stopy o wysokiej entropii (high-entropy alloy - HEA) mają doskonałe właściwości mechaniczne, jednak ich obrabialność jest prawie nieznana. Tu przedstawiono wyniki badania toczenia narzędziem diamentowym wspomaganego drganiami ultradźwiękowymi (UVDT) stopu FeCrCoMnNi i porównano je z rezultatami konwencjonalnego toczenia diamentowego (CDT).

3

Rozdrabianie struktury motoryzacyjnego stopu AISi7Mg mieszaninami soli i zaprawą AITi5B - wpływ na czystość stopu i wybranie właściwości użytkowe

Janus Arkadiusz, Zych Jerzy S., Smorawiński Zdzisław

Przegląd Odlewnictwa

|

2020

|

Vol. 70, nr 3-4

76--81

PL

W pracy przedstawiono wyniki badań prowadzonych w warunkach przemysłowych. Badania dotyczą wieloparametrowej ocenę skuteczności działania mieszanin technicznych soli modyfikujących stop AISi7Mg - tzw. rozdrabniaczy ziaren. Mieszaniny soli są wytwarzane przez grupę producentów i stanowią ofertę przemysłową. Porównano skuteczność działania pięciu rożnych mieszanin soli barowych i tytanowych oraz zaprawy modyfikującej AITi5B. Sole wprowadzano do kąpieli metalowej metodą „na powierzchnie" po utworzeniu na niej leja, na skutek wysokich obrotów rotora rafinacji gazowej. Wszystkie sole zwiększają właściwości wytrzymałościowe stopu po obróbce cieplnej T6 (Rm.Rp02, A5, HB). Równolegle stwierdza się w badaniach, iż technika wprowadzania soli „na powierzchnię'' zwiększa liczbę wtrąceń niemetalowych w stopie. Wtrącenia, w przypadku wytwarzania obręczy kół samochodowych (felg), jeśli zostaną rozmieszczone na powierzchni odlewu, mogą stanowić przyczynę zabrakowania.

EN

The results of tests performed under industrial conditions are presented in the hereby paper. Investigations concern multi-parameter assessments of the efficiency of technological salts mixtures - the so-called grains crushers - modifying the AISi7Mg alloy. Mixtures of salts are produced by a group of producers and constitute the industrial offers. The efficiency of operations of five different mixtures of barium and titanium salts as well as of the AITi5B inoculant, were compared. Salts were introduced to the metal bath by the method: 'on the surface' after making a pouring cap in it, due to a high speed rotor of the gaseous refining. All salts increase strength properties of alloys after the heat treatment T6 (Rm.Rp02, A5, HH). It was also found in tests, that the salts introduction by means of 'on the surface' technique increases the number of non-metallic inclusions in the alloy. If such inclusions remain on the casting surface, they can constitute the reason of the casting rejection, in case of the production of wheel rims.

4

Corrosion properties of Mg-Zn-Ca-(Cu, Au) metallic glasses in artificial physiological fluid

Cesarz-Andraczke Katarzyna, Nowosielski Ryszard, Babilas Rafał

Archives of Civil and Mechanical Engineering

|

2019

|

Vol. 19, no. 3

716--723

EN

The Mg-Zn-Ca-(Cu,Au) alloys were considered as resorbable materials for orthopedic short- term implants. The aim of this paper was to determine the influence of Au and Cu addition on corrosion properties of Mg69Zn25Ca5Au1, Mg69Zn25Ca5Au0.5Cu0.5 and Mg69Zn25Ca5Cu1 metallic glasses. The analysis of corrosion results allowed to describe the influence of 0.5 and 1 at.% of Au and Cu on the corrosion resistance in artificial physiological fluid. The Mg69Zn25Ca5Au0.5Cu0.5 and Mg69Zn25Ca5Cu1 metallic glasses exhibit lower corrosion resis-tance in comparison with Mg69Zn25Ca5Au1 alloy. The increase of Cu content caused the increase of hydrogen evolution volume and the high cathodic activity. The Mg69Zn25Ca5Au1 metallic glass shows the decrease of hydrogen evolution volume and manifests the low corrosion current density and the high polarization resistance, indicating the high corrosion resistance.

5

Odporność na korozję stopów wykorzystywanych w armaturze pożarniczej, narażonych na działanie wodnych roztworów

Roguski J., Kubis D., Ślęczkowski B., Skorupka K.

Przemysł Chemiczny

|

2018

|

T. 97, nr 10

1641--1644

PL

W urządzeniach stosowanych w ochronie przeciwpożarowej najczęściej wykorzystywanymi materiałami konstrukcyjnymi są stopy metali. Ze względu na różnorodne warunki środowiskowe ich eksploatowania mogą być one narażone w różnym stopniu na proces korozji. Ponieważ od wyrobów stosowanych w ochronie przeciwpożarowej oczekuje się wysokiej odporności na warunki środowiskowe przeprowadzono badania odporności elementów armatury pożarniczej na proces korozji. Wykonano badania wpływu wody wodociągowej, wybranych środków pianotwórczych oraz środka dekontaminacyjnego na proces korozji stopów metali najczęściej wykorzystywanych do produkcji armatury przeciwpożarowej (aluminium AK11, stal St3S, mosiądz Mo58).

EN

Low-alloy Mn steel, Al-Si alloy and brass samples were tested for corrosion resistance in aq. solns. of foam-forming agents used in fire extinguishing. The corrosion rate was lower than that in a decontamining agent and in water used for comparison.

6

Badania dylatometryczne w zastosowaniu do stopów metali

Morawiec M., Król M., Grajcar A.

LAB Laboratoria, Aparatura, Badania

|

2018

|

R. 23, nr 6

30--33

7

Oxide layers on titanium obtained by anodizing in orthophosphoric acid

Wilk M., Klimek L.

Archives of Materials Science and Engineering

|

2018

|

Vol. 94, nr 1

11--17

EN

Purpose: Titanium is an essential material used in modern dentistry, mostly due to its tissue compatibility. However, there are another physicochemical assets, which can be harnessed. One of these is enhancing the bonding strength of titanium with another materials. In view of the advantageous effect of oxide layers on the bond with the ceramics, an attempt was made at creating oxide layers on samples of commercially pure titanium applied as the material for metal frameworks of prosthetic restorations. Design/methodology/approach: As the research material cylindrical wet grinded commercially pure titanium, Grade II samples were used. The samples were divided into three groups and underwent anodic oxidation in 1 M orthophosphoric acid, with the voltages: 120 V, 160 V, 200 V. After the anodizing process, the samples were subjected to the X-ray diffraction, analysis of the element distribution from the surface towards the inside of the materials using an optical spectrometer, finishing with the tests performed with a scanning microscope to determine the morphology of the obtained layers. Findings: Layers of 0.26 pm to 0.65 pm thick were achieved. The performed studies demonstrated that increasing reaction voltage contributes not only to thickening of the oxide layers but also influences to porosity. The layers obtained in the electrolyte which contained monomolar orthophosphoric acid consist of only one allotropic type of titanium oxide - anatase. The spectrometric tests showed that the content of titanium and oxygen in the layer is not constant, which proves that the formed layer does not have a strictly stoichiometric composition TiO2, but rather TiO2-x. Research limitations/implications: It is necessary to provide the optimal voltage directly related to the employed acid solution to preserve the usable thickness of oxide layers. Too thick (over 1 pm) coating may lead to exfoliating. Contrary, distinctly thin layers present fractures and decrements, accordingly do not veneer entire surface of titanium sample. Originality/value: Usually oxide layers obtained by anodic oxidation are examined paying special attention to tissue integration and usability in implantology. Following paper is focused on bonding titanium with dental ceramics to facilitate process of designing porcelain-fused-to-metal fixed dentures.

8

Impact of Zn and Ca on dissolution rate, mechanical properties and GFA of resorbable Mg–Zn–Ca metallic glasses

Nowosielski R., Cesarz-Andraczke K.

Archives of Civil and Mechanical Engineering

|

2018

|

Vol. 18, no. 1

1--11

EN

This article presents investigations utility of Mg-based metallic glasses for resorbable orthopedic implants. Exploration of biocompatible Mg–Zn–Ca alloys in order to determine Zn and Ca optimum concentration were conducted, based on three criteria: sufficiently high GFA (glass forming ability), sufficiently high tensile strength, microhardness and the suitable dissolution rate (corrosion rate) in Ringer's solution. Fulfillment of these criteria should ensure bone union before implant dissolution. The optimatization of Ca and Zn concentration in the range of 4–6 at.% Ca and 28–32 at.% Zn was executed. The samples in form of ribbons (0.02–0.05 mm thickness) and rods (about diameter up to 4 mm) with amorphous structure were produced. These investigations allowed to determine the GFA. The optimal results for Mg66Zn30Ca4 and Mg64Zn32Ca4 alloys: tensile strength: 191–166 MPa, microhardness: 291–263 HV and volume of released hydrogen 0.04–0.12 ml/cm2/h. The corrosion studies - immersion and potentiodynamic methods were conducted (including measurement specific corrosion current density for Mg alloys). Finally, a comparative analysis was performed, which indicated the impact of Ca and Zn concentration on: GFA, mechanical properties and dissolution rate of studied metallic glasses.

9

Materiały z których wytwarza się elementy instrumentów muzycznych

Wójcik S.

Analit

|

2018

|

Nr 5

28

PL

Muzyka jest dziedziną z zakresu sztuk pięknych. Jest elementem kultury który towarzyszy człowiekowi od wieków. Była i jest ważnym elementem ceremoniom religijnym, ale również stanowi istotną część kultury. Jednak nie było by muzyki gdyby nie instrumenty na których się ją wykonuje. Z pojęciem instrumentu muzycznego nieodzownie łączą się materiały z których są wykonane. Początkowo trzon instrumentów stanowiły materiały którymi obdarowała nas natura takie jak rogi zwierząt, rośliny czy dary morza. W późniejszych latach w miarę rozwoju człowieka materiały z jakich wykonuje się instrumenty uległy zmianie. Prezentacja poświęcona będzie zagadnieniom z zakresu wykorzystania różnych materiałów, naturalnych i syntetycznych, do wytwarzania instrumentów muzycznych takich jak waltornia, struny do gitar i pianin oraz budowie i materiałom jakie wykorzystuje się do wykonania organ piszczałkowych. Wystąpieniu będzie przyświecało motto: „Sztuka, rzemiosło, a może już nauka”.

10

Gładkościowe nagniatanie ślizgowe stopów metali i kompozytów na osnowie metalowej

Czechowski K., Toboła D.

Mechanik

|

2017

|

R. 90, nr 7

552--554

PL

Przedstawiono wyniki badań prowadzonych w Instytucie Zaawansowanych Technologii Wytwarzania (IZTW) dotyczących możliwości nagniatania ślizgowego stopów metali i kompozytów na osnowie metalowej. Zamieszczone wyniki obejmują m.in. analizę struktury geometrycznej powierzchni oraz mikrostruktury i zmian mikrotwardości warstwy wierzchniej wybranych materiałów.

EN

Results of the research performed at the Institute of Advanced Manufacturing Technology (IAMT) regarding the possibility of slide burnishing of metal alloys and metal matrix composites are presented. Results include among others, analysis of surface geometry, microstructure and microhardness changes of the surface layer for selected materials.

11

Semi-continuous caster for plate

Haga T., Miyazaki K.

Journal of Achievements in Materials and Manufacturing Engineering

|

2017

|

Vol. 84, nr 2

58--67

EN

Purpose: Development of a semi-continuous caster that can cast a single plate and a clad plate of Al-40%Sn-1%Cu alloy used for sliding bearings. Design/methodology/approach: A semi-continuous caster to cast a single plate and a clad plate directly from molten metal was designed and assembled. The cast single plate has a thickness ranging from 10 mm to 30 mm, a width of 400 mm, and a length of 500 mm to 1,000 mm. The cast clad plate has a thickness ranging from 10 mm to 30 mm, a width of 50 mm, and a length of 300 mm. Findings: The semi-continuous caster successfully produced both a single plate and a clad plate of Al-40%Sn-1%Cu alloy. Influence of casting conditions on the properties of the plate, including the thickness, porosity, and surface quality were investigated in the single plate casting. The mixing and diffusion of the alloy elements at the interface was also investigated in the clad plate casting. Research limitations/implications: The cast Al-40%Sn-1%Cu alloy plate has not yet been tested as a sliding bearing material, so the efficacy of the material still requires investigation. Practical implications: The semi-continuous caster described in this paper enables the “small lot” production made from single and clad plates of aluminium alloy. Originality/value: Development of a semi-continuous caster that can cast both single and clad plates of aluminium alloy. Investigation of the relationship between the casting conditions and plate quality.

12

The effect of chemical composition on microstructure and properties of TRIP steels

Kučerová L., Bystrianský M.

Journal of Achievements in Materials and Manufacturing Engineering

|

2016

|

Vol. 77, nr 1

5--12

EN

Purpose: Various alloying strategies can be used to produce advanced high strength steels and this work offers comparison of results achieved for four different low alloyed steels with 0.2-0.4 %C, 0.5-2 %Si, 0.6-1.5 %Mn, 0.03-0.06 %Nb and with 0.8-1.33 %Cr. Microstructures obtained by two methods of thermo-mechanical treatment were analysed for each steel and compared with theoretical predictions of TTT (time temperature transformation) diagrams calculated by JMatPro. Design/methodology/approach: Thermo-mechanical treatment of all steels was carried out at thermo-mechanical simulator. Resulting microstructures were analyses by the means of scanning electron microscopy, mechanical properties were measured by tensile test. Findings: It was found out that microstructures typical for TRIP (transformation induced plasticity) steels can be obtained easily for low carbon steels alloyed by silicon or aluminium-silicon and micro-alloyed by niobium. Chromium addition influenced austenite decomposition causing intensive pearlite formation in low carbon steel and predominantly martensitic microstructure in middle carbon steel. These microstructures were not in agreement with calculated TTT diagrams. Research limitations/implications: To obtain ferritic-bainitic microstructure with retained austenite typical for TRIP steels, chromium alloyed steels require substantial optimisation of processing parameters. This issue should be addressed in future work. Practical implications: JMatPro software is well equipped to calculate TTT diagrams for steels alloyed by manganese, silicon and niobium, however further chromium addition changed behaviour of the steel in a way that the software was not able to predict. Originality/value: Obtained results could be useful for consideration of chemical composition of low alloyed steels with respect to resulting microstructures and properties.

13

Influence of niobium on the structure and properties of the matrix of high-speed steel with nickel

Pacyna J., Dziurka R., Grudzień M.

Inżynieria Materiałowa

|

2016

|

Vol. 37, nr 6

335--340

EN

The following paper investigates two model alloys simulating the quenched matrix of high-speed steels with an addition of 1.5% Ni, which was enriched with 1% and 2% of Nb to increase abrasion resistance. Based on the alloys’ composition comprising of W, Mo, V and Cr, the simulations of the quenched matrix of the high-speed steels indicate sufficiently high hardenability. The purpose of increasing the nickel content in the composition of such alloys was to increase their crack resistance, whereas the addition of the strongly carbide-forming niobium in amounts of 1% and 2%, balanced by an additional carbon content, was aimed at increasing the abrasion resistance of these steels. The authors of the above mentioned chemical composition concept expect that these types of alloys will be used in the production of tools (rolls) designed for the rolling of metallurgical products which are difficult to produce (flat bars, channel bars and tee bars). The quenching temperature of both alloys was optimised on the base of the so called quenching series. The accurate CCT diagrams and the tempering series for revealing the secondary hardness effect were also performed for these alloys. All investigation stages were accurately documented by metallographic tests.

PL

W pracy postanowiono wznowić badania na osnowie zahartowanej stali szybkotnącej, jednakże jej skład uzupełniono dodatkiem około 1,5% Ni oraz dodatkami odpowiednio około 1% i 2% Nb. Dodatki niobu, jeżeli tylko zostaną zbilansowane odpowiednimi dodatkami węgla, powinny dzięki utworzeniu stabilnych węglików Nb4C3 zwiększyć odporność na ścieranie stopu, a dodatki niklu powinny zwiększyć jego odporność na pękanie. Takie postępowanie powinno umożliwić uzyskanie materiału narzędziowego odpornego na ścieranie oraz odpornego na pękanie o właściwościach zahartowanej osnowy stali szybkotnących. Autorzy składu chemicznego nowych stopów i ich koncepcji spodziewają się, że będą one stosowane do wytwarzania narzędzi (walców) przeznaczonych do walcowania produktów hutniczych, które są trudne do wytworzenia (płaskowników, ceowników oraz teowników).

14

The influence of the distribution of nonmetalic inclusion on the fatigue strength coefficient of high purity steels

Lipiński T.

Journal of Achievements in Materials and Manufacturing Engineering

|

2015

|

Vol. 69, nr 1

18--25

EN

Purpose: In this study, attempts were made to analyze the impact of impurities with various diameters and spacing between non-metalic inclusion λ on fatigue strength coefficient k determined under rotary bending fatigue conditions zgo of high purity steels produced in an industrial plant. Design/methodology/approach: The study was performed on 21 heats produced in an industrial plant. Fourteen heats were produced in 140 ton electric furnaces, and 7 heats were performed in a 100 ton oxygen converter. The experimental variants were compared in view of the applied melting technology and heat treatment options. The results were presented to account for the correlations between the fatigue strength coefficient during rotary bending, the diameter of and spacing between submicroscopic impurities. Findings: Equations for calculating the fatigue strength coefficient at each tempering temperature and a general equation for all tempering temperatures were proposed. Equations for estimating the fatigue strength coefficient based on the relative volume of submicroscopic non-metallic inclusions were also presented. The relationship between the fatigue strength and hardness of high-grade steel vs. the quotient of the diameter of impurities and the spacing between impurities, and the fatigue strength and hardness of steel vs. the relative volume of non-metallic impurities were determined. Practical implications: The proposed linear regression equations supported the determination of fatigue strength coefficient k and bending fatigue strength as a function of hardness taking into account impurities. Originality/value: The proposed equations contributes to the existing knowledge base of practices impact of impurities with various diameters and spacing between non-metalic inclusion on fatigue strength.

15

Structural stability of nickel superalloy IN740H after ageing in 750°C

Hernas A., Kościelniak B., Bednarczyk I.

Journal of Achievements in Materials and Manufacturing Engineering

|

2015

|

Vol. 69, nr 1

5--9

EN

Purpose: Constant demand for electric energy as well as legal and ecological conditions of the country motivate the construction of advanced ultra-supercritical AUSC power units. Increase of the steam parameters to about 700°C and pressure to over 30 MPa requires the application of modern nickel superalloys, which need to be characterized by structural stability at high temperature. The paper presents the results of analysis of structural changes of IN740H superalloy after ageing at 750°C. Design/methodology/approach: Alloy specimens were aged at 750°C for 100 h, 500 h and 1000 h. Evaluation of structure was carried out with the use of light, scanning and scanning-transmission microscopy techniques as well as microanalysis of chemical composition with the use of X-ray spectrometer with energy dispersion (EDS). Findings: The microstructure analyses applying light and electron microscopy revealed the precipitation processes occurring in the structure of IN740H alloy. It has been shown the changes of morphology of γ’ phases and carbides due to heat treatment. Practical implications: The research carried out enabled to know the structural changes of IN740H during ageing at high temperature, which are determined the mechanical and physicochemical properties of alloy. Originality/value: Applied quantity and quality methodology of testing and achieved results of tests broaden the state of knowledge which refers to superalloys of nickel which are recommended to be applied in construction of super-ultra-supercritical boilers (AUSC).

16

Microstructural banding in titanium alloys

Krawczyk J., Dąbrowski R., Łukaszek-Sołek A., Frocisz Ł., Górecki K., Cios G., Śleboda T., Kopyściański M., Bała P.

Journal of Achievements in Materials and Manufacturing Engineering

|

2015

|

Vol. 72, nr 1

5--13

EN

Purpose of this paper was to investigate the phenomenon of microstructural banding in three titanium alloys: Ti-6Al-4V, Ti-10V-2Fe-3Al and Ti-3Al-8V-6Cr-4Mo-4Zr. Design/methodology/approach: The microstructure of the investigated materials in as-delivered condition was characterized. Compression tests were performed on Gleeble thermomechanical simulator to investigate banding phenomena occurring in the microstructure of each studied alloy. Moreover, banding phenomena was also investigated in the case of forging obtained from Ti-6Al-4V alloy. Heat treatment conditions allowing to reduce banding in the microstructure of the investigated alloys were also determined. Findings: Thermomechanical processing leading to dynamic recrystallization in the investigated alloys restricts the formation of bands in their microstructure. Homogenizing treatment can also reduce banding in such alloys. Research limitations/implications: Future research should concern the investigations of grain size in the recrystallized alloys and in the alloys subjected to homogenizing heat treatment. Practical implications: The results of this research should allow obtaining homogenous microstructure in titanium alloys studied in this paper. Originality/value: The range of the temperature and strain rate for dynamic recrystallization restricting banding in the microstructure in the investigated alloys was determined. In the case of Ti-3Al-8V-6Cr-4Mo-4Zr alloy the range of the temperature and time of annealing leading to homogenization of the material was identified.

17

Strength properties of the low-melting-point alloys

Wierzbicki Ł.

Journal of Achievements in Materials and Manufacturing Engineering

|

2014

|

Vol. 67, nr 1

26--31

EN

Purpose: The aim of this paper was to determine the strength and elasticity of low melting point alloys. In particular, the laboratory tests were observed to check the shape of the compression curve. This is a result of recrystallization. Design/methodology/approach: The strength and stiffness of the low melting point alloys was found. The unusual shape of the compression curve was observed. In order to determine if it is the result of crystallization, the samples were cooled in the liquid nitrogen. In the next step another attempt will be perform to the compression. Findings: The results of the compression tests and their analysis are presented. Research limitations/implications: Presented research was limited to alloys in the form of small samples. The developed technology of this type of preparation of this type alloys is limited to small volumes because the melts are small and expensive. Practical implications: The low melting point alloys have many possible applications. First of all they are materials with higher thermal conductivity and electrical conductivity. Conducted research programme showed that these materials exhibit also good the mechanical properties. Originality/value: Carrying out of the experiment that explaining of the shape of the compression curve for low-melting-points alloys. This experiment may be have a high educational value for the study. This experiment can have high an educational value for the science.

18

Ocena odporności korozyjnej stopów metali stosowanych jako materiały konstrukcyjne w mokrej wapiennej technologii odsiarczania spalin

Masalski J., Drela I., Szczygieł B

Przemysł Chemiczny

|

2013

|

T. 92, nr 6

986--990

19

Stopy na osnowie fazy międzymetalicznej TiAI I ich obróbka cieplna

Szkliniarz W.

Piece Przemysłowe & Kotły

|

2013

|

9-10

8--12

PL

W artykule w oparciu o najnowsze publikacje źródłowe oraz oryginalne wyniki badań własnych przedstawiono charakterystykę nowej generacji stopów tytanu na osnowie uporządkowanej fazy międzymetalicznej TiAI, konkurencyjnych wobec konwencjonalnych stopów tytanu oraz nadstopów niklu. Przedstawiono najważniejsze właściwości tej grupy stopów oraz wskazano aktualne i możliwe obszary ich zastosowania. Charakteryzując poszczególne etapy rozwoju tych stopów w okresie ostatnich kilkudziesięciu lat, starano się udzielić odpowiedzi na pytania:, jaki jest stan aktualny i perspektywy dla tych stopów, jakie bariery należy pokonać i problemy rozwiązać, aby stały się one zamiennikami drogich i ciężkich nadstopów niklu. Scharakteryzowano także skład chemiczny poszczególnych generacji stopów, ich mikrostrukturę oraz oddziaływanie mikrostruktury na właściwości. Opisując przemiany fazowe występujące podczas nagrzewania i chłodzenia po-kazano możliwości ich wykorzystania do kształtowania mikrostruktury i właściwości w procesach obróbki cieplnej stosowanych na poszczególnych etapach wytwarzania i przetwarzania tych stopów. Szczególną uwagę poświęcono nowej, autorskiej metodzie wieloetapowej obróbki cieplnej prowadzącej do ukształtowania wymaganej mikrostruktury tej grupy stopów, której najważniejszymi etapami są: wyżarzanie ujednorodniające, cykliczna obróbka cieplna, wyżarzanie niezupełne i wyżarzanie zupełne.

EN

In this paper, based on the latest publications on the source and original results of research presents the characteristics of a new generation of titanium alloys on the base of an ordered TiAl intermetallic phase competing with conventional titanium alloys and nickel superalloys. The paper presents the main characteristics of this group of alloys and identifies current and possible areas of application. In describing the various stages of the development of these alloys in the last few decades, attempts to answer the questions: what is the current status and prospects for these alloys, the barriers to be overcome and problems to solve, so that they become substitutes for expensive and heavy nickel superalloys. Characterized also the chemical composition of each generation alloys, their microstructure and microstructure effect on the properties. Describing the phase transformations that occur during heating and cooling is shown the possibility of their use in the formation of the microstructure and Describing the phase transformations that occur during heating and cooling is shown the possibility of their use in the formation of the microstructure and properties of the thermal treatment applied at the various stages of production and processing of these alloys. Particular attention was paid to the new method, multi-stage proprietary heat treatment leads to the formation of the desired microstructure of the alloy group, whose main steps are: homogenization annealing, cyclic heat treatment, under-annealing and full annealing.

20

The phase transformations during continuous cooling of Ti6Al7Nb alloy from the two-phase α+β range

Dąbrowski R.

Journal of Achievements in Materials and Manufacturing Engineering

|

2013

|

Vol. 59, nr 1

7--12

EN

Purpose: The phase transformations during continuous cooling from the two-phase α+β range in Ti6Al7Nb alloy has been determined. Design/methodology/approach: The phase transformations during continuous cooling of investigated alloy was elaborated using an L78 R.I.T.A dilatometer of the German Linseis Company. The microstructure of investigated alloy cooled from the two-phase α+β range was examinated by a light microscope Axiovert 200MAT. The measurements of hardness were performed with the Vickers HPO 250 apparatus. Findings: The relationship between cooling rate and microstructure morphology, hardness as well as dilatation effects has been determined. Research limitations/implications: The results will be used for the interpretation of phase transformations occurring at continuous cooling and at tempering from as-quenched state of the investigated alloy. Currently, the investigations of the kinetics phase transformation at continuous heating from as-quenched state will help to performed the Continuous-Heating-Transformation diagrams (CHT). These diagrams show the possibility of the regulation of the progress of successive (intermediate) transformations at tempering and thus influence the final alloy properties, including their hardness and fracture toughness. It is expected that the determination of final mechanical properties by means of regulating the progress of successive transformations occurring during heating from the as-quenched state is possible also in the Ti6Al7Nb alloy. Practical implications: The obtained results will be applied for the optimization of the heat treatment technology and for achieving the required mechanical properties of the Ti6Al7Nb alloy. Originality/value: The obtained results, supported in the future by additional cooling curves, will be used for the development of the original, full CCT diagram of the Ti6Al7Nb alloy cooled continuously from the two-phase α+β range.