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Progress in structured and textured cutting tools. Part 1. New designs and methods of fabricating of structured and textured cutting tools

Grzesik Wit

Mechanik

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2022

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R. 95, nr 4

6--11

EN

This paper presents new designs of structured and textured working surfaces of cutting tools made of different materials such as HSS, uncoated and coated sintered carbides, and superhard materials (PCD and CBN). A review of applied fabricating techniques including: micro-grinding, micro-EDM, micro-ECM, laser surface technology (LST), focused ion beam (FIB) and photolithography is done. Some recently published data concerning research works in the area of fabricating micro-/nano-textures of different geometrical configuration and functionality are discussed.

PL

W artykule przedstawiono nowe rozwiązania konstrukcyjne strukturyzowanych i teksturyzowanych powierzchni roboczych ostrzy skrawających wykonanych z różnych materiałów narzędziowych - stali szybkotnących, powlekanych węglików spiekanych oraz materiałów supertwardych (PCD i CBN). Dokonano przeglądu technik wytwarzania, w tym: mikroszlifowania, micro-EDM, micro-ECM, laserowej obróbki powierzchniowej, obróbki skoncentrowanym strumieniem jonów i fotolitografii. Omówiono wyniki ostatnio opublikowanych prac badawczych w zakresie wytwarzania mikro- i nanostruktur o różnej konfiguracji geometrycznej i funkcjonalności.

2

Study on modalities and microdefects of Al-Cu bimetallic tube by underwater explosive cladding

Yu Yong, Xu Peibao, Li Kai, Zhao Jun, Dai Yuntong, Ma Honghao, Yang Ming

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 4

1390--1398

EN

In this study, a screwed copper tube was cladded an aluminum tube by a new explosive cladding method. To study the modalities of the bonding interface, a light microscope was used to observe the bonding interface. To expose the weak position of the interface, a three-point bending test was conducted under extreme condition. Then the BSE (Backscattering Electron) images of the bent interfaces were obtained. Meanwhile, the EDS (Energy Disper-sive Spectrometry) analyses of the melted zone were performed. The results of the light microscopic observations show that there are four bonding modalities on the interface. They can be summarized to two bonding modalities: direct bonding and bonding with the melted zone. There are no macro cracks on the interface of the bent specimens, which represents a reliable joining generally. The elastic modulus of Al-Cu bimetallic tube along the axial direction is 85.2Gpa. The BSE images, the EDS analyses and the microhardness tests show the direct bonding with some characteristics of the micro wavy interface is a pretty nice bonding pattern. The melted zone composed of CuAl2 is a weak bonding pattern, which may affect the mechanical property of the joint.

3

Influence of electromagnetic riveting process on microstructures and mechanical properties of 2A10 and 6082 Al riveted structures

Dong Dongying, Sun Liqiang, Wang Qiong, Li Guangyao, Cui Junjia

Archives of Civil and Mechanical Engineering

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2019

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Vol. 19, no. 4

1284--1294

EN

Electromagnetic riveting (EMR) technology had unique connection advantages compared to traditional riveting methods. The influence of EMR process on microstructures and mechani- cal properties for 2A10 and 6082 aluminum riveted structures was investigated by comparison with regular pressure riveting (RPR) process. The microstructures and mechanical properties of the two riveting processes were analyzed by optical microscopy and tensile testing machine, respectively. The micro-hardness and the interference amount were also investi- gated. The results showed that the main characteristic of the driven head was the shear zone. The grain deformation of the EMR in shear zone was more severe than that of the RPR. The width of the shear zone of the RPR was larger than that of the EMR. The trend of micro- hardness distribution was opposite along the direction of the shear zone. Meanwhile, the distribution of the interference amounts of EMR had a better uniformity. The failure mecha- nisms of shear tests of the EMR and RPR were same, but the pull-out tests were different. The dynamic loading had a great influence on the microstructures and mechanical properties of riveted structures, and the mechanical properties of EMR were significantly enhanced.

4

Passive methods of boiling heat transfer enhancement

Orman Ł. J., Radek N., Kapjor A., Karpisz D.

Technical Transactions

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2018

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Vol. 115, iss. 12

193--198

EN

The paper presents the issue of boiling heat transfer enhancement with the use of different passive techniques, namely the application of wire mesh coatings, capillary porous layers, pin – fins and laser treatment. Enhanced boiling heat transfer has been described as well as the research data of the authors that deals with microstructural coatings. The conducted experimental tests confirm the possibility of increasing heat fluxes transferred at the same superheat value due to the use of heat transfer enhancing techniques.

PL

W artykule przedstawiono zagadnienie intensyfikacji wymiany ciepła przy wrzeniu poprzez zastosowanie różnych pokryć tj. struktur siatkowych, kapilarno – porowatych, mikrożeber czy obróbki laserowej. Przybliżono zagadnienie intensyfikacji wymiany ciepła przy wrzeniu i opisano wyniki badań autorów, dotyczące intensyfikacji wrzenia na mikropowierzchniach strukturalnych. Przeprowadzone badania potwierdzają możliwości zwiększenia gęstości odbieranych strumieni ciepła przy tym samym przegrzaniu.

5

Analysis of the mechanical properties and of micrographs of refill friction stir spot welded 7075-T6 aluminium sheets

Kubit A., Kluz R., Trzepieciński T., Wydrzyński D., Bochnowski W.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 1

235--244

EN

The main aim of the investigations was to determine the significance of parameters of RFSSW for the strength parameters of the resulting joint. RFSSW joints were made in 0.8-mm-thick 7075-T6 aluminium alloy using different welding parameters (tool rotational speed v, tool plunge depth, and joining time). The load capacity of joints was determined by shear tests. The optimum welding parameters which assure the highest load capacity (4.09 kN) in the tensile/shear test are: tool rotational speed of 3000 rpm, tool plunge depth of 1.55 mm, and joining time of 1.25 s. In the conditions of the static tensile test under pure shear the highest joint capacity (6.48 kN) is found for the joint welded at a tool plunge depth of 1.7 mm. Depending on the tool plunge depth, three types of joint damage were observed during tensile/shear tests: plug type fracture, shear fracture, and plug-shearracture. Incomplete refill is the main weld defect observed which is located on the path along which the sleeve plunges into the sheet. It was also found that alclad between the upper and lower sheets worsens the joint quality between the stir zone and thermo-mechanically affected zone.

6

Morphological diversity of microstructures occurring in selected recent bivalve shells and their ecological implications

Brom K. R., Szopa K.

Contemporary Trends in Geoscience

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2016

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Vol. 5, iss. 2

104--112

EN

Environmental adaptation of molluscs during evolution has led to form biomineral exoskeleton – shell. The main compound of their shells is calcium carbonate, which is represented by calcite and/or aragonite. The mineral part, together with the biopolymer matrix, forms many types of microstructures, which are differ in texture. Different types of internal shell microstructures are characteristic for some bivalve groups. Studied bivalve species (freshwater species – duck mussel (Anodonta anatina Linnaeus, 1758) and marine species – common cockle (Cerastoderma edule Linnaeus, 1758), lyrate Asiatic hard clam (Meretrix lyrata Sowerby II, 1851) and blue mussel (Mytilus edulis Linnaeus, 1758)) from different locations and environmental conditions, show that the internal shell microstructure with the shell morphology and thickness have critical impact to the ability to survive in changing environment and also to the probability of surviving predator attack. Moreover, more detailed studies on molluscan structures might be responsible for create mechanically resistant nanomaterials.

7

Improved microstructure and mechanical properties of dissimilar explosive cladding by means of interlayer technique

Saravanan S., Raghukandan K., Hokamoto K.

Archives of Civil and Mechanical Engineering

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2016

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Vol. 16, no. 4

563--568

EN

Aluminium and copper plates are explosively cladded with Al 5052, copper and SS 304 interlayers and the results are reported. While continuous molten layer is obtained in conventional explosive clads, a smooth interface, devoid of defects, is obtained in interlayer laced explosive clads. The mechanical properties of interlayer laced explosive clads confirm higher kinetic energy utilization leading to stronger clad. Ram tensile, shear strengths and Vickers microhardness of Al–Cu explosive clad with different interlayers are higher than conventional two layer clad.

8

Sedimentological interpretation and stratigraphical position of glacigenic deposits in the Napęków area (Holy Cross Mountains, Poland)

Ludwikowska-Kędzia M., Pawelec H., Adamiec G.

Geologos

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2015

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Vol. 21, No. 4

261--284

EN

The identification of depositional conditions and stratigraphical position of glacigenic deposits in the Napęków area is important for the genetic and stratigraphical interpretation of Quaternary deposits in the central part of the Holy Cross Mountains, as well as for a revision of the course and extent of Middle Polish (Saalian) glaciations. These deposits comprise a series of diamictons which occur between sandy-gravelly deposits. Based on results of macro- and microscopic sedimentological investigations, analysis of heavy mineral composition, roundness and frosting of quartz grains, as well as OSL dating, this complex must have formed during the Odranian Glaciation (Drenthe, Saalian, MIS 6). Sandy-gravelly deposits are of fluvioglacial and melt-out origin. Diamictons represent subglacial traction till. Their facies diversity is a result of variations in time and space, complex processes of deposition and deformation, responsible for their formation at the base of the active ice sheet. This glacigenic depositional complex was transformed by erosion-denudation and aeolian processes in a periglacial environment during the Vistulian (Weichselian, MIS 5d-2).

9

The effect of the heat treatment on the 7CrMoVTiB10-10 steel's microstructure and its properties

Bolanowski P.

Challenges of Modern Technology

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2015

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Vol. 6, no. 2

10--14

EN

According to the European Standard PN-EN 10216-2 two types of the heat treatment could apply to 7CrMoVTiB10-10 – the modern bainitic boiler steel. The 7CrMoVTiB10-10 steel may have different properties, depending on the chosen method of the heat treatment. This paper shows the differences in the microstructure and the properties occuring after two processes: one of them including normalization and tempering, and the other – hardening and tempering.

10

Mechanical and microstructural properties of EN AW-6060 aluminum alloy joints produced by friction stir welding

Küçükrendeci I.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2015

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Vol. 63, nr 2

475--478

EN

In the study, the mechanical and microstructural properties of friction stir welded EN AW-6060 Aluminum Alloy plates were investigated. The friction stir welding (FSW) was conducted at tool rotational speeds of 900, 1250, and 1500 rpm and at welding speeds of 100, 150 and 180 mm/min. The effect of the tool rotational and welding speeds such properties was studied. The mechanical properties of the joints were evaluated by means of micro-hardness (HV) and tensile tests at room temperature. The tensile properties of the friction stir welded tensile specimens depend significantly on both the tool rotational and welding speeds. The microstructural evolution of the weld zone was analysed by optical observations of the weld zones.

11

Microstructure and Functional Properties of Prosthetic Cobalt Alloys CoCrW

Nadolski M., Golański G., Klimas J., Szota M., Szymański J.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 3A

1999--2003

EN

The material subject to investigation was two commercial alloys of cobalt CoCrW (No. 27 and 28) used in prosthodontics. The scope of research included performing an analysis of microstructure and functional properties (microhardness, wear resistance and corrosion resistance), as well as dilatometric tests. The examined alloys were characterized by diverse properties, which was considerably influenced by the morphology of precipitates in these materials. Alloy No. 27 has a higher corrosion resistance, whereas alloy No. 28 shows higher microhardness, better wear resistance and higher coefficient of linear expansion. Lower value of the expansion coefficient indicates less probability of initiation of a crack in the facing ceramic material.

PL

Badaniu poddano dwa komercyjne stopy kobaltu CoCrW (nr 27 i 28) stosowane w protetyce stomatologicznej. Zakres badań obejmował przeprowadzenie analizy mikrostrukturalnej, właściwości użytkowych (mikrotwardość, odporność na ścieranie i odporność korozyjna) oraz badania dylatometryczne. Badane stopy charakteryzowały się zróżnicowanymi właściwościami na co zasadniczy wpływ miała morfologia wydzieleń w tych materiałach. Stop nr 27 posiada wyższą odporność korozyjną natomiast stop nr 28 wykazuje: wyższą mikrotwardość, lepszą odporność na ścieranie oraz niższy współczynnik rozszerzalności liniowej. Niższa wartość współczynnika rozszerzalności liniowej wskazuje na mniejsze prawdopodobieństwo inicjacji pęknięcia licującego materiału ceramicznego.

12

Microstructural Characterization of Quenched and Plastically Deformed Two-Phase α+β Titanium Alloys

Motyka M., Sieniawski J., Mrówka-Nowotnik G.

Archives of Metallurgy and Materials

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2015

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Vol. 60, iss. 3A

2033--2037

EN

Development of microstructure in two-phase α+β titanium alloys is realized by thermomechanical processing – sequence of heat treatment and plastic working operations. Analysis of achieved results indicates that hot plastic deformation – depending on deformation degree – causes significant elongation of α phase grains. Following heat treatment and plastic deformation processes lead to their fragmentation and spheroidization. Characterization of microstructure morphology changes during thermomechanical processing of quenched Ti-6Al-4V and Ti-6Al-2Mo-2Cr alloys is presented in the paper. The effect of martensitic phase α’(α”) on microstructure development in plastic deformation process was confirmed.

PL

Kształtowanie mikrostruktury dwufazowych stopów tytanu α+β realizowane jest w procesie cieplno-plastycznym będącym sekwencją operacji obróbki plastycznej i przeróbki plastycznej. Analiza uzyskanych wyników badań wskazuje, że odkształcanie plastyczne na gorąco – w zależności od stopnia odkształecenia - powoduje wydłużanie ziarn fazy α. Kolejne operacje obróbki cieplnej lub odkształcania plastycznego prowadzą do ich fragmentacji i sferoidyzacji. W pracy przedstawiono charakteryzację zmian morfologii składników mikrostruktury stopów Ti-6Al-4V oraz Ti-6Al-2Mo-2Cr poddanych przechładzaniu na początkowym etapie procesu cieplno-plastycznego. Potwierdzono oddziaływanie fazy martenzytycznej α’(α”) w badanych stopach na przebieg procesu kształtowania ich mikrostruktury podczas odkształcania plastycznego.

13

Material parameters affecting degradation processes of Al-brasses in pipe systems

Liptáková T., Lovíšek M., Hadzima B., Dundeková S.

Archives of Materials Science and Engineering

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2015

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Vol. 76, nr 1

27--34

EN

Purpose: As construction material of cooling pipe systems there are often used Al-brasses because their high thermal conductivity, mechanical workability and corrosion resistance. In the pipes liquid media of various chemical compositions are flowing by different rates. It means that the material is loaded mechanically also chemically what results in synergy effect on degradation. Susceptibility to corrosion-erosion damage of four Al-brasses manufactured by different producers is investigated because in operation conditions they have different reliability and lifetime. Design/methodology/approach: By studying of their microstructure, surface state, selected mechanical properties and corrosion characteristics the parameters which affected chemicalmechanical degradation were evaluated. Experimental methods are SEM, EDX and spectral analyses, measurement of microhardness and roughness. Findings: By actual obtained results it was identified that in spite of very similar chemical composition differences in mechanical and corrosion behaviour are affected by technology of manufacturing. It can explain their different durability in operating conditions. Research limitations/implications: To identify more precisely the main parameters important for degradation resistance in various flow media the original experimental device is designed and constructed. The device makes possible to test Al-brasses in various flowing media by the same mail at three flowing rates. By long time lasted experiments in the one it is able to simulated operation specification. Results of the device are not presented yet because they are just in progress. Practical implications: Obtained results will be very helpful for choice of Al-brasses for required operation conditions according important properties which were experimentally verified. Originality/value: It means contribution to economy by material saving in operation by available choice and design and construction of original experimental device.

14

Research of Aluminium Influence on Tin Bronzes

Rzadkosz S., Garbacz-Klempka A., Kozana J., Piękoś M., Czekaj E., Perek-Nowak M.

Archives of Foundry Engineering

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2015

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Vol. 15, iss. 1 spec.

93--98

EN

During the research a group of copper and tin alloys was investigated. The influence of variable additions of aluminium within the range of 0.3 – 1.4 wt % was analysed on tin bronze CuSn10 with the aim of obtaining durable bronzes, from outside the normalized copper alloy groups. Melts were conducted in order to obtain alloy samples for testing the chosen properties. Metallographic and SEM-EDS tests were carried out to determine the microstructure changes caused by introducing Al addition to CuSn10 alloy. Also, chosen mechanical properties were tested for the alloys investigated. The results showed considerable changes in the microstructure as well as significant hardening of the Cu-Sn alloys as the result of aluminium addition. The thermal and dilatometric analysis confirmed the presence of phase changes, also their parameters were assessed depending on the share of aluminium addition in the CuSn10. The aluminium additive applied within the range of 0.3-1.4 wt% to CuSn10 bronze clearly impacted the microstructure and the strength properties analysed, causing the increase in strength and hardness with simultaneous insignificant decrease of elongation of the CuSn10Al alloys.

15

Study of properties and internal structure of modified restoration plasters

Nowek M.

Structure and Environment

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2014

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Vol. 6, no. 1

13--18

EN

Moisture in conjunction with salts can cause significant injury to construction materials. Highly porous and vapour-permeable restoration plasters are used in order to protect walls against moist due to capillary wicking and hygroscopic absorption of water, which are exposed to the harmful effects of salts. The structure of such plasters reduces the capillary conductivity inside the material. The purpose of research was to estimate physical properties of modified plaster mortars. Examination was focused on the impact of the addition of perlite, silica fume and air-entraining admixture on the following parameters: density, tensile strength, compressive strength, strength ratio, capillary absorption of water and water penetration. The microstructure of each material was examined using a scanning electron microscope.

16

Microstructure Control of High-alloyed White Cast Iron

Kawalec M.

Archives of Foundry Engineering

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2014

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Vol. 14, iss. 1

49--54

EN

This paper presents the results of studies of high-alloyed white cast iron modified with lanthanum, titanium, and aluminium-strontium. The samples were taken from four melts of high-vanadium cast iron with constant carbon and vanadium content and near-eutectic microstructure into which the tested inoculants were introduced in an amount of 1 wt% respective of the charge weight. The study included a metallographic examinations, mechanical testing, as well as hardness and impact resistance measurements taken on the obtained alloys. Studies have shown that different additives affect both the microstructure and mechanical properties of high-vanadium cast iron.

17

Granulation of Cu-Al-Fe-Ni Bronze

Pisarek B. P.

Archives of Foundry Engineering

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2014

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Vol. 14, iss. 3

61--66

EN

With the increase in wall thickness of the casting of iron-nickel-aluminium-bronze, by the reduction of the cooling rate the size of &κII phase precipitates increases. This process, in the case of complex aluminium bronzes with additions of Cr, Mo and W is increased. Crystallization of big κII phase, during slow cooling of the casting, reduces the concentration of additives introduced to the bronze matrix and hardness. Undertaken research to develop technology of thick-walled products (g> 6 mm) of complex aluminium bronzes. Particular attention was paid to the metallurgy of granules. As a result, a large cooling speed of the alloy, and also high-speed solidification casting a light weight of the granules allows: to avoid micro-and macrosegregation, decreasing the particle size, increase the dispersion of phases in multiphase alloys. Depending on the size granules as possible is to provide finished products with a wall thickness greater than 6 mm by infiltration of liquid alloy of granules (composites). Preliminary studies was conducted using drip method granulate of CuAl10Fe5Ni5 bronze melted in a INDUTHERM-VC 500 D Vacuum Pressure Casting Machine. This bronze is a starting alloy for the preparation of the complex aluminium bronzes with additions of Cr, Mo, W and C or Si. Optimizations of granulation process was carried out. As the process control parameters taken a casting temperature t (°C) and the path h (mm) of free-fall of the metal droplets in the surrounding atmosphere before it is intensively cooled in a container of water. The granulate was subjected to a sieve analysis. For the objective function was assume maximize of the product of Um*n, the percentage weight "Um" and the quantity of granules 'n' in the mesh fraction...

18

Effect of solution treatment on microstructures and mechanical properties of 2099 Al–Li alloy

Lin Y., Zheng Z. Q., Li S. C.

Archives of Civil and Mechanical Engineering

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2014

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Vol. 14, no. 1

61--71

EN

The influence of the solution treatment on microstructures and mechanical properties of 2099 Al–Li alloy was investigated by means of optical microscopy, scanning electron microscopy, transmission electron microscopy and tensile properties measurement. With increasing solution temperature, the quantity of primary particles in the alloy decreased, and the degree of recrystallization gradually increased, leading to softening of solution treated alloy. Dissolution of primary particles in the solution treatment process promoted δ′ and T1 phases to precipitate during sequent aging treatment resulting in increase of strength. The number of T1 phases increased to peak value when the alloy was solution treated at 540 °C because almost no further dissolution of Cu-containing particles occurred at higher temperature. However, exorbitant solution temperature caused the drastic increase in the size and quantity of recrystallized grains that softened the alloy. Thus, mechanical properties of aged alloy were determined by two mechanisms: precipitation strengthening and solution softening. Compared with solution temperature, solution time had less effect on microstructures and mechanical properties of alloy. The suitable solution treatment for 2099 Al–Li alloy was 540 °C for 1 h, treated by which the yield strength of the aged alloy was 604 MPa with the elongation of 7.9%.

19

Evaluation of microstructural changes of S235 steel after rolling on the basis of microscopic observations and eddy current non-destructive method

Kukla D., Bałkowiec A., Grzywna P.

Advances in Materials Science

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2014

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Vol. 14, nr 4(42)

40--48

EN

The aim of the study was to determine the microstructure and residual stress changes which appears in the S235 steel (which is designed for operating in elevated temperatures) during cold rolling. The changes of orientation, both morphological and crystallographic, are occurring as a result of the rolling process. Analysis of the results allowed to determine the change in grain morphology (size, shape), determination of grain morphology of the rolling direction and determination of crystallographic texture. The dislocation density present in the material before and after the cold rolling process was estimated on the basis of dislocation structure images obtained via transmission electron microscope. The observed microstructural changes were correlated with the results of nondestructive testing using eddy current method. They allowed for the identification of the state of stress measured on three different surfaces of the rolled sheet (parallel and perpendicular to the rolling direction). As the result the usability of using the non - destructuve techniques of stress level determination was proved.

20

Degradation of microstructure and mechanical properties of 15HM steel after 420 000 hours of service

Pietryka I., Golański G., Jasak J., Słania J., Urbańczyk P., Wieczorek P.

Advances in Materials Science

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2014

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Vol. 14, nr 4(42)

5--11

EN

The results of a microstructure examination and mechanical properties of 15HM (13CrMo4-5) steel are presented in the article. The examined elements are the samples taken from the live steam pipeline serviced for about 420 000 hours at the temperature of about 510°C, and pressure of 11 MPa. It has been shown that after long-term operation the examined steel has a ferritic-pearlitic microstructure with a dominant content of quasipolygonal ferrite. The processes of fragmentation of lamellar precipitates and their spheroidization were observed in pearlite. On the grain boundaries, single lamellar precipitations were observed. Moreover, numerous precipitations at the interface of three grain boundaries were revealed. The examined steel, despite its long-term service time, was characterized by the strength properties (YS, TS) slightly lower than the required minimum, the impact energy value KV equal to 20 J, and the transition temperature shifted to a temperature above zero. Relatively low level of degradation of the microstructure and mechanical properties of the investigated steel can result from high stability of the ferritic-pearlitic microstructure.