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1

Residual strength and toughness after impact loading for RC slabs strengthened with different layers of geogrid

Ahmed Aya M. E., Hamdy Osman, Saad Youssef L. Z., Ahmad Seleem S. E.

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2023

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Vol. 32, No. 2

117--134

EN

This study presents an experiment for investigating the residual strength and toughness of reinforced concrete, RC, and slab reinforced by a geogrid as shrinkage reinforcement along with lower tensile steel reinforcement. Three different parameters were considered, slab thickness, number of geogrid layers, and thickness of the upper concrete cover. Fifteen slab samples with sizes of 50 × 50 cm exposed to the impact load on its center before being re-load by the static load and six slab samples exposed to the static load only. The load and deflection relation were recorded through the static loading process for all specimens, where loading capacity, toughness, and toughness index were measured. The results show an enhancement in the slabs residual strength as the slab thickness and concrete cover increased. On the other hand, the residual strength of slabs has a remarkable decrease with the increase in geogrid layers. Moreover, the toughness has a positive relationship with the concrete cover and has an inverse relation with the slab thickness and the number of layers. A geogrid reduced the number and distribution of cracks and mitigated their severity, especially for double layers with the same concrete cover.

2

Enhancement of tensile performance of concrete by using synthetic polypropylene fibers

Jienmaneechotchai Thunyawee, Foytong Piyawat, Khunkitti Pirat, Sata Vanchai, Chindaprasirt Prinya

Przegląd Naukowy Inżynieria i Kształtowanie Środowiska

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2023

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Vol. 32, No. 4

320--337

EN

The research attempted to investigate the effect of polypropylene fibers (PP fibers) on the mechanical characteristics of concrete. According to ASTM C39/C39M and ASTM C 1609/C1609M, standard testing methods were used to examine the concrete compressive and flexural strength, post-cracking behavior, and toughness. The mechanical properties were evaluated at different ages of concrete curing, namely 1 day, 7 days, and 28 days, and for different quantities of fiber volume portions, specifically 0.0%, 0.5%, and 1.0%. The results demonstrate that a fiber volume of 0.5% is the most effective in obtaining the highest compressive strength. The recorded values at the related testing ages were 31.07 MPa, 41.51 MPa, and 46.68 MPa. Additionally, the utilization of 0.5% and 1.0% volume of PP fiber in concrete resulted in improved flexural strength and post-cracking performance. The toughness values for these mixes were 2.0 and 2.6 times higher than those for the plain concrete. Upon analyzing the fracture surface, there was a homogeneous distribution of fibers, which played a significant role in enhancing the overall functionality of the concrete. The research validated that the inclusion of polypropylene fibers substantially enhanced the mechanical characteristics of concrete, emphasizing the potential of fiber reinforcement in concrete-based implementations.

3

Comparison of Tensile Properties of Nb Grain Refined A206 Alloy by Gravity and Tilt Casting

Palamutcu Nuri, Dizdar Kerem Can, Sahin Hayati, Dispinar Derya

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 4

49--53

EN

Turbulent filling of a mould is one of the ways to introduce extrinsic defects into the cast part that could deteriorate many properties of any casting. The turbulence can be easily eliminated by counter gravity casting. In gravity casting, tapered downsprue, tapered runner is needed such that the mould cavity is filled counter-gravity from the bottom which is the only best way to eliminate turbulence during filling. Tilt casting method also exists which has the potential to quiescently transfer the liquid into the mould cavity. In this work, gravity and tilt casting methods were used to evaluate the tensile properties of Nb grain refined 206 alloy. Three different Nb contents were investigated: 0.025, 0.05 and 0.1 wt% ratios and it was found that 0.05 wt% revealed the highest tensile properties. On the other hand, when the intrusion of surface folded oxides was eliminated during filling, it was found that mechanical properties were increased significantly, and particularly, the toughness was increased by two folds when tilt casting was applied compared to gravity casting.

4

Influence of material thickness on the ductile fracture of steel plates for shipbuilding

Jakub Kowalski, Janusz Kozak

Polish Maritime Research

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2022

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nr 3

160--166

EN

In the shipbuilding industry, the risk of brittle fractures is relatively high because some units operate in arctic or subarctic zones and use high thickness (up to 100 mm) steel plates in their structures. This risk is limited by employing certified materials with a specific impact strength, determined using the Charpy method (for a given design temperature) and by exercising control over the welding processes (technology qualification, production supervision, and non-destructive tests). However, for offshore constructions, such requirements may prove insufficient. For this reason, regulations employed in constructing offshore structures require conducting crack tip opening displacement (CTOD) tests for steel and welded joints with thicknesses exceeding 40 mm for high tensile strength steel and 50 mm for other steel types. Since classification codes do not accept the results of CTOD tests conducted on specimens of sub-sized dimensions, the problem of theoretically modelling the steel construction destruction process is of key importance, as laboratory tests for notched elements of considerable thickness (100 mm and higher) are costly and problems stemming from high loads and a wide range of recorded parameters are not uncommon. The aim of this research is to find a relationship between material thickness and CTOD value, by establishing and verifying a numerical model that allows recalculating a result obtained on a sub-size specimen to a full- size specimen for a ductile fracture mode. This work presents results and conclusions from numerical modelling and compares them with laboratory test results of the elastic-plastic properties of high thickness steel, typically used in offshore applications.

5

Study on the mechanical behaviors and failure mechanism of polyurethane cement composites under uniaxial compression and tension

Yilin Pi, Wenhua Zhang, Wanting Zou, Yunsheng Zhang

Archives of Civil and Mechanical Engineering

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2022

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Vol. 22, no. 1

art. no. e18, 2022

EN

The brittle nature of concrete limits the further development, while the addition of polymer can enhance the toughness and improve the working performance. Understanding the mechanical properties and failure mode of polyurethane cement composites (PUCC) is of great significance in the field of construction engineering. To solve these issues, in this paper, the tensile and compressive properties are studied. The tensile/compressive strength, elastic modulus, toughness, strain capacity and the failure mechanism were analyzed. The results showed that compared with the reference group (RF), the compressive strength of PUCC was decreased by 33%. However, rubber powder could enhance the toughness of samples up to 1.19 times than RF. Polyethylene fiber was hard to disperse because of the poor fluidity of the matrix, therefore, the mechanical properties of PUCC did not change obviously. But due to the bridging effect of fiber, the failure mode was relative intact. Not only the irregular shape of basalt would decrease the interfacial adhesion, but also the polyurethane has weakened the cohesion. The mechanical properties of concrete were reduced because of the formation of interfacial transition zone between basalt and cement matrix. Therefore, the tensile and compressive strength was decreased by 19.7% and 11.8%, respectively. Moreover, the incorporation of basalt shortens the deformation time and intensifies the failure degree of the specimen. Moreover, this study takes a three-stage model to describe the compressive stress–strain behavior of PUCC. There is a good correlation between the constitutive model and the experimental results, and the simulation is accurate.

6

Microstructure, toughness and hardness of a simulated HAZ in steel S1100QL and of the HAZ of an actual MAG-welded joint made using a metallic flux-cored wire

Łomozik Mirosław

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2021

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Vol. 65, No. 5

47--65

EN

Simulation tests discussed in the article involved structural steel S1100QL having a yield point of more than 900 MPa. The simulations included single (Tmax = 1250°C) and double welding thermal cycle (Tmax = 1250°C + 600°C, Tmax = 1250°C + 760°C and Tmax = 1250°C + 900°C) as well as cooling times t8/5 = 3, 5 and 10 s. Specimens with the simulated heat affected zone (HAZ) were subjected to impact strength tests performed at a temperature of -40°C and +20°C, Vickers hardness tests (HV10) and microscopic metallographic tests (involving light microscopy). Test results were presented in diagrams and photographs. Related comparisons included results of the structural, hardness and toughness tests of simulated HAZs with analogous results obtained during the actual repair welding of a MAG-welded joint made of steel S1100QL. The final part of the article contains discussion concerning the test results and the statement concerning the obtainment of the significant conformity of the phase composition and the morphology of the microstructure as well as the average hardness values of the HAZ areas obtained in the simulations and those of the HAZ area obtained in the actual welded joint. In relation to all tested simulation variants, the impact energy of the simulated HAZ area of steel S1100QL satisfied the minimum criterion of KV = 27 J both in relation to a test temperature of -40°C and that of +20°C. The number of repeated (1 through 4) thermal cycles having preset parameters did not trigger explicitly noticeable changes in impact energy values as regards the simulated HAZ of steel S1100QL.

PL

Przedmiotem badań symulacyjnych opisanych w artykule była stal konstrukcyjna o granicy plastyczności powyżej 900 MPa typu S1100QL. Zostały przeprowadzone symulacje dla pojedynczego (Tmax= 1250°C) i podwójnego cyklu cieplnego spawania (Tmax= 1250°C + 600°C, Tmax 1250°C + 760°C oraz Tmax= 1250°C + 900°C), dla czasów chłodzenia t8/5= 3, 5 i 10 s. Próbki z zasymulowanymi obszarami SWC poddano badaniom udarności w temperaturach -40°C oraz +20°C, pomiarom twardości sposobem Vickersa HV10 oraz badaniom metalograficznym mikroskopowym przy użyciu mikroskopii świetlnej. Wyniki badań zestawiono na wykresach i na zdjęciach fotograficznych. Porównano uzyskane wyniki badań: strukturalnych, twardości oraz udarności symulowanych obszarów SWC z analogicznymi wynikami badań rzeczywistego naprawczego złącza spawanego stali S1100QL, wykonanego metodą MAG. Na zakończenie omówiono wyniki badań i stwierdzono m.in. że uzyskano dużą zgodność składu fazowego i morfologii mikrostruktury oraz średnich wartości twardości obszarów SWC otrzymanych w wyniku symulacji i obszaru SWC w naprawczym złączu spawanym. Ponadto praca łamania symulowanego obszaru SWC stali S1100QL, dla wszystkich badanych wariantów symulacji, spełniała kryterium minimalnego KV = 27 J zarówno przy temperaturze badania -40°C, jak i +20°C. Krotność powtórzeń cyklu cieplnego o zadanych parametrach w zakresie od jednokrotnego do czterokrotnego nagrzewania nie powodowała jednoznacznej tendencji zmian wartości pracy łamania symulowanych obszarów SWC stali S1100QL.

7

Analysis of the cracking process of layered composites with polyester-glass recyclate using dynamic tests

Panasiuk Katarzyna, Kyzioł Lesław, Hajdukiewicz Grzegorz

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2019

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nr 57 (129)

73--78

EN

Layered composites are materials that are widely used in industry due to their low manufacturing costs. They are used, among others, as a construction material for the construction of light aircraft, cars, wind turbine blades and the hulls of vessels. The universality of their use has contributed to the formation of a large amount of post-production and post-use waste from these composites. Layered composites, using recycled polyester and glass, or recycled composite waste, may be materials that could be used in the economy. The polyester-glass waste used in the composite was created by crushing and then grinding and sieving to obtain the appropriate granulation. Materials with a waste content of 0%, 10%, 20% and with granulation of this waste of ≤ 1.2 mm were made using the hand lamination method. Test specimens were prepared from the material plates that were obtained in accordance with the PN-EN ISO 179-1: 2010E standard (Plastics – Charpy Impact Assessment – Part 1: Non-instrumental impact test). Impact tests of samples were carried out according to the above-mentioned standards using a Zwick Roell RKP450 swinging hammer. Test bench instrumentation and software enabled the bending forces to be recorded, as well as the deflection of the samples for short time intervals and displacement, so a detailed force-deflection graph could be obtained. During the analysis, the results of the research were focused on describing the kinetics of the process where the samples were destroyed (fracture mechanics), this allowed for the initial determination of the material’s resistance to dynamic loads. The results obtained showed that the increase of the recycled content in the produced composite contributed to the lowering of the destructive force threshold in the impact tests, as well as the simultaneous increase of the plasticity of the material. The increase of the sample’s deflection with the occurrence of the maximum force resulted in the energy of the elastic state being increased (Ue).

8

Influence of the content of a glass-polyester recycled additive on the properties of layered composites in dynamic tests

Panasiuk K., Hajdukiewicz G.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2018

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nr 56 (128)

36--40

EN

Polyester-glass composites are widely used in many industries, in various types of constructions, including dynamically loaded ones. This article examines the influence of the content of a glass-polyester recycled additive on the strength properties of layered composites. The recyclate was polyester-glass waste, which was pre-crushed and then milled into the appropriate fractions. Manual laminating technology was used to make the materials. The composite materials were made with a waste content of 0%, 10%, 20% and granulations of ≥ 1.2 mm and ≥ 3 mm. Samples for testing were prepared in accordance with the PN-EN ISO 179-1: 2010E standard (Plastics – Charpy Impact Assessment – Part 1: Non-instrumental impact test). Impact tests of the samples were performed using the Charpy method with the Zwick Roell RKP450 swinging hammer. The test results showed that the addition of polyester-glass recyclate, its content %, and its granulation size, have an impact on the composite resistance to loads in dynamic tests.

9

Optimization of multistage artificial aging parameters on Al-Cu alloy mechanical properties

Tsamroh D. I., Puspitasari P., Andoko, Permanasari A. A., Setyawan P. E.

Journal of Achievements in Materials and Manufacturing Engineering

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2018

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Vol. 87, nr 2

62--67

EN

Purpose: This research is aimed to describe heat treatment process by using multistage artificial aging for Al-Cu alloy with Taguchi method in Minitab 16 to optimize the heat treatment parameters. This research conducted due to the applied of aluminium alloy in automotive industrial and aircraft industrial that has good properties for fabrication. Design/methodology/approach: Methodology that use in this paper is experimental design with statistical approach. Three controllable parameters were selected, they were temperature aging, holding time of aging, and the number of stages. The hardness value and impact value after multistage artificial aging were chosen as quality characteristics. The experiment was performed using orthogonal arrays of L9 (33). Findings: The finding that resulted in this research are the most significant parameters that affected hardness and toughness value of Al-Cu alloy against multistage artificial aging. The optimal hardness and toughness for Al-Cu alloy were obtained with heat treatment at temperature 200ºC, holding time for 6 hours, with two stages artificial aging. Research limitations/implications: The limitation that found in this research is even optimal level had been determined, it is unable to determine the true optimal value of each design parameters. Practical implications: This optimization process can be applied in manufacture process in industrial without spend expensive cost and time. Originality/value: According to research result, can be understood that by conducting these experiments, the impact value and the hardness value of Al-Cu alloy increase with multistage artificial aging treatment.

10

Właściwości mechaniczne kompozytu Al2O3-ZrO2-grafen

Boniecki M., Wesołowski W., Gołębiewski P., Kaszyca K., Woluntarski M., Piątkowska A., Romaniec M., Ciepielewski P., Krzyżak K.

Materiały Ceramiczne

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2017

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T. 69, nr 4

317--321

PL

W pracy zbadano wpływ płatków grafenowych na właściwości mechaniczne kompozytu o zawartości wagowej 20% Al2O3-80% ZrO2 (stab. 3%mol Y2O3). Do wykonania próbek użyto handlowego proszku ceramicznego firmy Tosoh oraz tlenku grafenu (GO) otrzymanego w ITME. Kompozyty otrzymano na bazie wodnych (GO) mieszanin obu składników, które po wysuszeniu spiekano metodą SPS. Wykonano kompozyty o zawartości wagowej od 0% do 1% GO. Spektroskopia Ramana wykazała obecność grafenu w próbkach po spiekaniu. Stwierdzono, że w funkcji zawartości GO odporność na pękanie ma maksimum dla zawartości 0,02% GO (wzrost o 7% w porównaniu do matrycy), wytrzymałość maleje, moduł Younga oraz twardość Vickersa utrzymują się stałe do zawartości 0,2% GO, a następnie maleją.

EN

The effect of graphene flakes on mechanical properties of a composite containing 20 wt.% Al2O3 and 80 wt.% ZrO2 (stabilised with 3 mol.% Y2O3) was studied. A commercial ceramic powder produced by Tosoh (Japan), and graphene oxide (GO) made at the Institute of Electronic Materials Technology (Poland) were used to obtain samples. The composites were obtained basing on aqueous mixtures of both components. After drying, they were sintered by the SPS method. The composites contained from 0% to 1% of GO by weight. Raman spectroscopy revealed the presence of graphene in sintered samples. It has been stated the influence of GO content on mechanical properties of the composites, i.e. fracture toughness had a maximum for 0.02% GO (increased by 7% in comparison to the GO-free matrix), and afterwards strength decreased in the whole GO content range, Young's modulus and Vickers hardness remained constant up to 0.2% GO, and then decreased.

11

The influence of heat treatment on toughness of extruded profiles from EN AW-6082 aluminium alloy

Romański P., Stradomski G., Wiewiórska S., Szarek A.

Hutnik, Wiadomości Hutnicze

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2017

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Vol. 84, nr 1

66--69

EN

The aim of this work was to analyze the influence of heat treatment on toughness of hot extruded aluminium profiles from EN AW-6082 aluminium alloy. The result of the conducted research has shown that the heat treatment had a significant effect on the toughness of aluminium profiles. In the study was found that the highest values of toughness were achieved after annealing process of hot extruded aluminium profiles.

PL

Celem pracy była analiza wpływu obróbki cieplnej na udarność wyciskanych na gorąco profili ze stopu aluminium EN AW-6082. Wyniki przeprowadzanych badań wykazały, że obróbka cieplna ma istotny wpływ na udarność profili aluminiowych. W badaniach stwierdzono, że najwyższą wartość udarności uzyskano po przeprowadzonym procesie wyżarzania wyciskanych na gorąco profili aluminiowych.

12

Porównanie wybranych właściwości mechanicznych laminatu z kompozytem przekładkowym z korkowym rdzeniem

Kukliński M.

Autobusy : technika, eksploatacja, systemy transportowe

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2017

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R. 18, nr 12

1004--1007, CD

PL

W artykule przedstawiono i omówiono wyniki badań udarnościowych oraz statycznych prób zginania laminatów i kompozytów z przekładką korkową grubości 4 mm, wykonanych na bazie dwóch żywic poliestrowych: ortoftalowej A105 oraz izoftalowej K530. Próbki na bazie żywicy A105 wykazały większą sztywność oraz zdolność przenoszenia większych naprężeń normalnych przy zginaniu, natomiast próbki wykonane na bazie żywicy izoftalowej K530 wykazały większą udarność. Żywica A105 charakteryzująca się mniejszą lepkością lepiej przesączała przekładkę korkową zwiększając sztywność i opóźniając proces rozwarstwienia kompozytu przekładkowego.

EN

This paper discussed selected mechanical properties of laminates and cork sandwich composites based on orthophthalic and isophthalic polyester resins. Due to lower viscosity and greater flexural modulus, the orthophthalic resin A105 may be applied for construction of part of vehicle body, that are not subject to impact. The same structures based on isophthalic resin K530 may be used for vehicle body parts subject to impact forces due to its capacity of energy absorbation.

13

Effect of gradient temperature rolling (GTR) and cooling on microstructure and properties of E40-grade heavy plate

Gaosheng L., Wei Y., Qingwu C., He Z.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 1

121--131

EN

Despite numerous investigations on gradient temperature rolling (GTR) and its influence on grain refining, no research exists on appropriate cooling after GTR, which is important in the microstructural control. This work focuses on the effect of final microstructure on heavy-plate properties and microstructural evolution during different rolling and cooling processes. GTR and uniform temperature rolling (UTR) were applied to E40-grade heavy plates. GTR plates were maintained at 1073 K at their surface and 1473 K at their core. After rolling, experimental plates were cooled at a series of rates. Their microstructure and mechanical properties were studied. The plate prepared using GTR and air cooling had the best integrated property because of its uniform and fine ferrite microstructure. The GTR plate strength increased gradually with a corresponding decrease in toughness as the cooling rate increased. The uniform temperature rolling plate cooled in water exhibited the worst mechanical properties.

14

Badanie własności mechanicznych stali drobnoziarnistej Domex 700MC

Mazur M.

Zeszyty Naukowe. Quality. Production. Improvement

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2016

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No. 1 (4)

107--119

PL

W rozdziale przedstawiono wyniki badań własności mechanicznych stali drobnoziarnistej Domex 700MC. Badania prowadzone w ramach badań własności zmęczeniowych stali klasyfikowanych do aplikacji nowych materiałów w konstrukcjach naczep samochodowych. Przedstawione badania obejmują wyniki statycznej próby rozciągania oraz udarności w zakresie temperaturowej – 70 do + 100°C. Analiza badań uzupełniona została o analizę struktury materiału oraz spektrometryczną analizę składu chemicznego materiału.

15

Nowe staliwo ledeburytyczne o osnowie umacnianej wydzieleniowo

Pacyna J.

Prace Instytutu Odlewnictwa

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2016

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Vol. 56, no. 1

3--6

PL

Zaprojektowano nowe staliwo ledeburytyczne o osnowie umacnianej wydzieleniowo związkami międzymetalicznymi, którego skład chemiczny uzupełniono zbilansowanym węglem i dodatkiem około 4,25% V. Uzyskano skłonną do umacniania związkami międzymetalicznymi martenzytyczno-austenityczną osnowę z siatką ledeburytu na granicach krystalitów. Twardość (około 400 HV20) i praca złamania KV (około 3 J) nowego tworzywa są minimalnie większe od tych samych właściwości dotychczas stosowanego staliwa G200CrNiMo4-3-3, które głównie stosowane jest na walce bruzdowe w walcowniach średnich i dużych. O zastosowaniu w praktyce przemysłowej nowego staliwa zdecydują jego właściwości tribologiczne.

EN

A new ledeburite cast steel was designed based on a matrix precipitation hardened with intermetallic compounds of a chemical composition enriched by adding about 4.25% V totally balanced with carbon. A martensitic-austenitic matrix with a ledeburite network at the crystallite boundary prone to the strengthening effect with intermetallic compounds was obtained. Both hardness (about 400 HV20) and fracture energy KV (about 3 J) of the new material are only slightly superior to the same properties offered by the cast G200CrNiMo4-3-3 steel used so far for the section rolls operating in medium and large rolling mills. The applicability of the new cast steel in industrial practice will mainly depend on its tribological properties.

16

Kompozyt Al2O3-ZrO2 wzmocniony płatkami grafenowymi

Boniecki M., Gołębiewski P., Wesołowski W., Woluntarski M., Zybała R., Kaszyca K., Piątkowska A., Romaniec M., Ciepielewski P., Krzyżak K.

Materiały Elektroniczne

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2016

|

T. 44, nr 1

20--28

PL

W pracy zbadano wpływ płatków grafenowych na właściwości mechaniczne kompozytu o zawartości wagowej 20% Al2O3 - 80% ZrO2 (stab. 3% mol. Y2O3). Do otrzymania próbek użyto handlowy proszek ceramiczny firmy Tosoh, tlenek grafenu (GO) otrzymany w ITME oraz grafen firmy SkySpring Nanomaterials Inc. (GN). Kompozyty otrzymano na bazie wodnych (GO) i alkoholowych (GN) mieszanin obu składników, które po wysuszeniu spiekano w piecu Astro pod jednoosiowym ciśnieniem i metodą SPS. Wykonano kompozyty o zawartości wagowej: 0; 0,1; 0,2; 0,5; 1 i 3% GO oraz 0,1% GN. Spektroskopia Ramana wykazała obecność grafenu. Stwierdzono, że w funkcji zawartości GO oraz GN: odporność na pękanie ma maksimum dla zawartości 0,1% GO i GN, wytrzymałość maleje, moduł Younga oraz twardość Vickersa utrzymują się stałe do zawartości 0,5% GO, a następnie maleją.

EN

This research addresses the effect of graphene flakes on the mechanical properties of the composite containing 20 wt. % Al2O3 and 80 wt. % ZrO2 (stab. 3 mol. % Y2O3). The samples were made from a commercial ceramic powder produced by Tosoh, graphene oxide (GO) from ITME and graphene purchased from Skyspring Nanomaterials Inc. (GN). The obtained composites based on an aqueous (GO) and alcohol (GN) mixtures of both components were first dried and then sintered under an uniaxial pressure in an Astro furnace and in a SPS machine. The composites weight content equaled to: 0; 0.1; 0.2; 0.5; 1 and 3% of GO and 0.1% GN. Raman spectroscopy revealed the presence of graphene. It was found that as a function of the GO and GN content, the fracture toughness has a maximum for 0.1% GO and GN, the strength decreases, the Young's modulus and Vickers hardness remain constant up to 0.5% GO, and then decrease.

17

Effect of vanadium microaddition on the microstructure and mechanical properties of casing pipes after normalizing process

Kiczor M., Przegrałek P., Grajcar A.

Journal of Achievements in Materials and Manufacturing Engineering

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2016

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Vol. 78, nr 1

11--20

EN

Purpose: The aim of the paper is to determine the impact of vanadium microaddition on mechanical properties and microstructure of two steel grades with a different content of V, applied for production of casing pipes used in the extractive industry. Design/methodology/approach: Pilger process technology with subsequent normalizing was used. The tests were carried out on an industrial batch produced in the Rurexpol Department, and the research was done with the use of industrial research laboratories of Alchemia S.A. Group. The microstructure and mechanical properties were determined in the initial state and after normalizing at two temperatures: 940°C and 880°C. Static tensile test and Charpy V impact test have been applied. Findings: Mechanical properties, macrostructure and microstructure of steel pipes, obtained during production under industrial conditions, have been analyzed in the article. The effects of V content and hot-working and normalizing treatment affect substantially the mechanical properties and microstructure of the investigated steels. Research limitations/implications: It was found that the application of vanadium microaddition to the normalizing process after the hot-rolling has a beneficial effect on a strength-toughness balance only at a narrow range of technological parameters of the normalizing. Practical implications: The knowledge of the vanadium microaddition effect on the industrial production route is indicated in the paper. Originality/value: : The effect of vanadium microaddition has been proved to be very sensitive to the temperature conditions of the heat treatment.

18

The influence of heat treatment on toughness of extruded profiles from EN AW-6063 aluminium alloy

Romański P., Stradomski G., Pilarczyk J. W.

Hutnik, Wiadomości Hutnicze

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2016

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Vol. 83, nr 5

223--227

EN

The aim of this work was to analyze the influence of heat treatment on toughness of hot extruded aluminium profiles from EN AW-6063 aluminium alloy. The result of the conducted research has shown that the heat treatment had a significant effect on the toughness of aluminium profiles. In the study it was found that the highest values of toughness were achieved after supersaturation process of hot extruded aluminium profiles.

PL

Celem pracy była analiza wpływu obróbki cieplnej na udarność wyciskanych na gorąco profili ze stopu aluminium EN AW-6063. Wyniki przeprowadzanych badań ukazały, że obróbka cieplna ma istotny wpływ na udarność profili aluminiowych. W badaniach wykazano, że najwyższą wartość udarności uzyskano po przeprowadzonym procesie przesycania wyciskanych na gorąco profili aluminiowych.

19

Effect of Heat Treatment Parameters on the Toughness of Unalloyed Ausferritic Ductile Iron

Guzik E., Sokolnicki M., Nowak A.

Archives of Foundry Engineering

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2016

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Vol. 16, iss. 2

79--84

EN

Studies were carried out to determine the effect of heat treatment parameters on the plastic properties of unalloyed ausferritic ductile iron, such as the elongation and toughness at ambient temperature and at – 60°C. The effect of austenitizing temperature (850, 900 and 950°C) and ausferritizing time (5 - 180 min.) at a temperature of 360°C was also discussed. The next step covered investigations of a relationship that is believed to exist between the temperature (270, 300, 330, 360 and 390°C) and time (5, 10, 30, 60, 90, 120, 150, 180, 240 min.) of the austempering treatment and the mechanical properties of unalloyed ausferritic ductile iron, when the austenitizing temperature is 950°C. The “process window” was calculated for the ADI characterized by high toughness corresponding to the EN-GJS-800-10-RT and EN-GJS-900-8 grades according to EN-PN 1564 and to other high-strength grades included in this standard. Low-alloyed cast iron with the nodular graphite is an excellent starting material for the technological design of all the ausferritic ductile iron grades included in the PN-EN-1624 standard. The examined cast iron is characterized by high mechanical properties stable within the entire range of heat treatment parameters.

20

Kwestia udarności, normalizowania i walcowania termomechanicznego stali do budowy mostów w świetle normy PN-82/S-10052 oraz norm EN, rynku i praktyki budowlanej

Kożuch M., Lorenc W., Rabiega J., Kowalska C., Ochojski W., Rykaluk K.

Mosty

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2015

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nr 3

43--46

PL

W artykule przedstawiono kwestie dotyczące udarności, normalizowania i walcowania termomechanicznego na tle zapisów „starych i nowych” norm oraz realiów produkcji obecnych stali.